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National Fire Protection Association 1 Batterymarch Park, Quincy, MA 02169-7471 Phone: 617-770-3000 • Fax: 617-770-0700 • www.nfpa.org

NEC Code-Making Panel 3

Second Draft Meeting Agenda

November 2-7, 2015

San Diego, CA

Item No. Subject 15-11 -1 Call to Order 15-11-2 Introduction of Members and Guests 15-11-3 Approval of A2016 First Draft Meeting Minutes 15-11-4 Review of Meeting Procedures and Revision Schedule 15-11-5 Task Group Reports 15-11-6 Process Public Comments and Develop Second Revisions 15-11-7 Fire Protection Research Foundation Requests 15-11-8 Old Business 15-11-9 New Business 15-11-10 Adjournment

Public Comment No. 1063 Global Input Lawrence Ayer

Public Comment No. 462 Section No. 300.4 ROBERT JENSEN

Public Comment No. 1028 Section No. 300.4 Christel Hunter

Public Comment No. 1165 Section No. 300.4(B) james dorsey

Public Comment No. 1425 Section No. 300.5(A) submitted

Public Comment No. 1219 Section No. 300.5(D)(3) Marcelo Hirschler

Public Comment No. 1392 Section No. 300.5(D)(3) submitted

Public Comment No. 1395 Section No. 300.5(D)(3) submitted

Public Comment No. 970 Section No. 300.5(D)(4) WILLIAM NOACK

Public Comment No. 99 Section No. 300.7(B) DAVID KENDALL

Public Comment No. 1641 Section No. 300.9 submitted


Public Comment No. 879 Section No. 300.11 Marcelo Hirschler

Public Comment No. 122 Section No. 300.11(B)(1) Aaron Adamczyk

Public Comment No. 801 Section No. 300.11(B)(1) Marcelo Hirschler

Public Comment No. 498 Section No. 300.12 Phil Simmons

Public Comment No. 1151 Section No. 300.19(A) Christel Hunter

Public Comment No. 580 Section No. 300.20(B) Carl Johnson II

Public Comment No. 1788 Section No. 300.22(B) submitted

Public Comment No. 163 Section No. 300.22(C)(3) Aaron Adamczyk

Public Comment No. 555 Section No. 300.3(B)(1) ALFIO TORRISI

Public Comment No. 108 Section No. 300.37 CARL JOHNSON II





Public Comment No. 246 Section No. 300.37 Matt Szabo

Public Comment No. 416 Section No. 300.37 John Bogart

Public Comment No. 826 Section No. 590.4(G) James Dollard

Public Comment No. 1143 Section No. 590.4(J) LORI WEIDNER

Public Comment No. 615 Section No. 590.6(B) NEHAD EL‐SHERIF

Public Comment No. 691 Section No. 725, Part IV. Terry Peters

Public Comment No. 969 Section No. 725.1 Randall Wright

Public Comment No. 460 Section No. 725.3(C) ROBERT JENSEN

Public Comment No. 1397 Section No. 725.3(K) submitted


Public Comment No. 74 Section No. 725.24 DAVID KIDDOO

Public Comment No. 602 Section No. 725.121(A) Stanley Kaufman

Public Comment No. 689 Section No. 725.133 Terry Peters

Public Comment No. 447 Sections 725.135(K), 725.135(L), 725. ROBERT JENSEN


Public Comment No. 223 Section No. 725.135(K) DAVID KIDDOO

Public Comment No. 224 Section No. 725.135(L) DAVID KIDDOO

Public Comment No. 225 Section No. 725.135(M) DAVID KIDDOO




Public Comment No. 866 Section No. 725.179(B) Marcelo Hirschler

Public Comment No. 454 Section No. 760.3(B) ROBERT JENSEN

Public Comment No. 75 Section No. 760.24(A) DAVID KIDDOO



Public Comment No. 461 Section No. 760.176 ROBERT JENSEN

Public Comment No. 869 Section No. 760.176(D) Marcelo Hirschler

Public Comment No. 450 Section No. 760.179(C) ROBERT JENSEN

Public Comment No. 870 Section No. 760.179(E) Marcelo Hirschler

Public Comment No. 1063-NFPA 70-2015 [ Global Input ]

Article 100 Definitions

Voltage, Nominal…..Informational Note No. 3: Certain 48-volt DC battery units have a charging float voltage up to 58 volts. In DCapplications 60 volts is used to cover the entire range of float voltages.

Article 110

110.27 Guarding of Live Part(A) Live Parts Guarded Against Accidental Contact. Except as elsewhere required or permitted by this Code, live parts ofelectrical equipment operating at 50 volts AC/60 volts DC or more shall be guarded against accidental contact by approvedenclosures or by any of the following means:

Article 200 Use and Identification of Grounded Conductors

200.7

(B) Circuits of Less Than 50 Volts AC. A conductor with white or gray color insulation or three continuous white stripes orhaving a marking of white or gray at the termination for circuits of less than 50 volts AC shall be required to be grounded only asrequired by 250.20(A).C) Circuits of 50 Volts AC or More. The use of insulation that is white or gray or that has three continuous white or gray stripesfor other than a grounded conductor for circuits of 50 volts AC or more shall be permitted only as in (1) and (2).

Article 215 Feeders

215.12(C)(2) Feeders Supplied from Direct-Current Systems.Where a feeder is supplied from a dc system operating at more than 50 60 volts, each ungrounded conductor of 4 AWG orlarger shall be identi?ed by polarity at all termination, connection, and splice points by marking tape, tagging, or otherapproved means; each ungrounded conductor of 6 AWG or smaller shall be identi?ed by polarity at all termination,connection, and splice points in compliance with 215.12(C)(2)(a) and (b). The identi?cation methods utilized forconductors originating within each feeder panelboard or similar feeder distribution equipment shall be documented ina manner that is readily available or shall be permanently posted at each feeder panelboard or similar feederdistribution equipment.Article 430 Motors, Motor Circuits, and Controllers

430.232 Where Required. Exposed live parts of motors and controllers operating at 50 volts DC or more between terminalsshall be guarded against accidental contact by enclosure or by location as follows:

430.233 Guards for Attendants. Where live parts of motors or controllers operating at over 50 volts AC to ground are guardedagainst accidental contact only by location as specified in 430.232, and where adjustment or other attendance may benecessary during the operation of the apparatus, suitable insulating mats or platforms shall be provided so that the attendantcannot readily touch live parts unless standing on the mats or platforms.

Article 445 Generators

445.14 Protection of Live Parts. Live parts of generators operated at more than 50 volts AC/60 volts DC to ground shall notbe exposed to accidental contact where accessible to unquali?ed persons.

Article 460 Capacitors

460.6 (A) Time of Discharge. The residual voltage of a capacitor shall be reduced to 50 volts DC , nominal, or less within 1minute after the capacitor is disconnected from the source of supply.

460.28(A) Means for Discharge. A means shall be provided to reduce the residual voltage of a capacitor to 50 volts DC or lesswithin 5 minutes after the capacitor is disconnected from the source of supply.Article 480 Storage Batteries

480.5 Overcurrent Protection for Prime Movers. Overcurrent protection shall not be required for conductors from a batterywith a nominal voltage of 60 volts DC or less if the battery provides power for starting, ignition, or control of primemovers. Section 300.3 shall not apply to these conductors.

480.6 DC Disconnect Methods. (A) Disconnecting Means. A disconnecting means shall be provided for all ungroundedconductors derived from a stationary battery system with a nominal voltage over 60 volts DC. A disconnecting meansshall be readily accessible and located within sight of the battery system.

Article 522 Control Systems for Permanent Amusement Attractions

522.25 Ungrounded Control Circuits. Separately derived ac and 2-wire dc circuits and systems 50 volts AC/60 volts DC orgreater shall be permitted to be ungrounded, provided that all the following conditions are met:

Article 625

625.18 Interlock. Electric vehicle supply equipment shall be provided with an interlock that de-energizes the electricvehicle connector whenever the electrical connector is uncoupled from the electric vehicle. An interlock shall not berequired for portable cord-and-plug-connected electric vehicle supply equipment intended for connection to

National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...

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receptacle outlets rated at 125 volts, single phase, 15 and 20 amperes. An interlock shall not be required for dcsupplies less than 50 60 volts dc.

625.19 Automatic De-Energization of Cable. The electric vehicle supply equipment or the cable-connectorcombination of the equipment shall be provided with an automatic means to de-energize the cable conductors andelectric vehicle connector upon exposure to strain that could result in either cable rupture or separation of the cablefrom the electric connector and exposure of live parts. Automatic means to de-energize the cable conductors andelectric vehicle connector shall not be required for portable cord-and-plug-connected electric vehicle supplyequipment intended for connection to receptacle outlets rated at 125 volts, single phase, 15 and 20 amperes. Aninterlock shall not be required for dc supplies less than 50 60 volts dc.

625.44 Electric Vehicle Supply Equipment Connection.

Electric vehicle supply equipment shall be permitted to be cord and plug-connected to the premises wiring system inaccordance with one of the following:

(A) Connections to 125-Volt, Single-Phase, 15 and 20-Ampere Receptacle Outlets. Electric vehicle supply equipment intendedfor connection to non-locking, 2-pole,3-wire grounding-type receptacle outlets rated at 125 V, single phase, 15 and 20 amperesor from a supply of less than 50 60 volts dc.

(4) Supply Circuits. The supply circuit to the mechanical ventilation equipment shall be electrically interlocked withthe electric vehicle supply equipment and shall remain energized during the entire electric vehicle charging cycle.Electric vehicle supply equipment shall be marked in accordance with625.15. Electric vehicle supply equipmentreceptacles rated at 125 volts, single phase, 15 and 20 amperes shall be marked in accordance with 625.15 andshall be switched, and the mechanical ventilation system shall be electrically interlocked through the switch supplypower to the receptacle. Electric vehicle supply equipment supplied from less than 50 60 volts dc shall be marked inaccordance with 625.15(C) and shall be switched, and the mechanical ventilation system shall be electricallyinterlocked through the switch supply power to the electric vehicle supply equipment.

Article 669 Electroplating

669.6 Wiring Methods. Conductors connecting the electrolyte tank equipment to the conversion equipment shall bein accordance with 669.6(A) and (B).

(A) Systems Not Exceeding 50 60 Volts Direct Current. Insulated conductors shall be permitted to be run without insulatedsupport, provided they are protected from physical damage. Bare copper or aluminum conductors shall be permitted wheresupported on insulators.

(B) Systems Exceeding 50 60 Volts Direct Current. Insulated conductors shall be permitted to be run on insulatedsupports, provided they are protected from physical damage. Bare copper or aluminum conductors shall be permittedwhere supported on insulators and guarded against accidental contact up to the point of termination in accordancewith 110.27.

A rticle 720 Circuits and Equipment Operating at Less than 50 Volts

Circuits and Equipment Operating at Less Than 50 Volts AC/60 Volts DC.

720.1 Scope. This article covers installations operating at less than 50 volts, alternating current, or 60 volts direct current oralternating current .

720.11 Mechanical Execution of Work. Circuits operating at less than 50 volts AC or 60 volts DC shall be installedin a neat and workmanlike manner. Cables shall be supported by the building structure in such a manner that thecable will not be damaged by normal building use.Type your content here ...

Statement of Problem and Substantiation for Public Comment

Over the past decade numerous code articles have been placed into the NEC as a result of the increased resurgence of DC systems. These systems, similar to their AC counterpart, have mandated code requirements that must be met when the system voltage exceeds a certain threshold. For years the system threshold for many of the requirements has been kept at the 50 volt level. While this is appropriate for AC systems, it can create confusion to the user of the document when applied to a 48 DC batteries during charging where a “float voltage” is common at 58 volts. The float voltage can vary significantly depending on battery chemistry, battery construction, and the actual ambient temperature. This voltage may be constant for the entire duration of the charge or can fluctuate. Some 48 volt DC systems stay above the 50 volt threshold for 99% of the time for applications such as telecommunications, UPS systems and emergency lighting.

This elevated voltage may create confusion since various AHJ’s might see 58 volts and mandate that a code rule must be followed since the 50 volt threshold has been increased. To resolve these issues a DC task group was formed to research the DC systems found in the NEC and to correlate the various DC topics that were being added to the NEC. The task group recommended the use of 60 volt DC throughout the code to eliminate the confusion that could arise from the elevated float voltage. The intent of the task group was to provide a consistent use of the voltage threshold within the NEC document.

For the 2017 NEC Revision Cycle, a task group was formed to correlate the use of the 50/60V threshold and provide public comments for the second draft. The task group members Larry Ayer (Chair), Bill Cantor, Donny Cook, Jim Dollard (Co-Chair), John Kovacik (DC Task Group Chair), Ernie Gallo, Vince Saporita, and Jim White provided input and guidance for these recommendations.

To correlate the use of 50 volts for AC systems and 60 volts for DC systems, the recommended NEC changes are based on the following:


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1. Where a code section refers to AC systems only and indicates 50 volts the acronym “AC” was added to provide clarity. 2. Where a code section refers to a requirement used only in a DC system at a 50 volt threshold, the voltage is revised to 60 volts and the term “DC” is added3. Where a code section indicates a 50 volt threshold, and the section is a requirement for both AC and DC systems, the text is revised as “50 volts AC/60 volts DC”.4. When a code section refers to DC systems, and the term “nominal” is used, it will be deleted since the voltage threshold is increased to 60 volts.5. A fine print note is being recommended in Article 100 below the definition for “Nominal Voltage” to provide additional information on float voltage.

NEC changes are being recommended for the following code sections:

1. *Add informational note after “Voltage, Nominal”. Informational note to read as follows:*

*Informational Note No. 3: Certain 48-volt DC battery units use a charging float voltage up to 58 volts. In DC applications 60 volts is used to cover the entire range of float voltages.*

2. For section 110.27, “50 volts” is being changed to “50 volts AC/60 volts DC”. This will clarify the voltage threshold for AC and DC systems.

3. Section 200.7 (B) and (C) applies to conductor marking for AC systems only. “AC” is added after 50 volts to clarify that this requirement is only for AC systems.

4. Section 210.5(C)(2) was revised in the First draft that changed “50 volts” to “60 volts” to correlate with the new microgrid article. Revise section 215.12(C) from“50 volts” to “60 volts” to correlate with section 210.5(C)(2).

5. In section 445.14, revise “50 volts” to 50 volts AC/60 volts DC” to clarify that this requirement pertains to both AC and DC systems.

6. In sections 480.5 and 480.6 “50 volts” was changed to “60 volts” since these pertain to DC batteries and DC systems.

7. In section 522.25, “50 volts” is being changed to “50 volts AC / 60 volts DC” to clarify that this section pertains to both AC and DC systems and distinguishes between the two voltage systems and thresholds.

8. Article 625, Electrical Vehicle Charging System. Revise the text from “50 volts” to“60 volts” since these are DC systems.

9. Section 669.6(A) and (B) are DC systems. Revise the text from“50 volts” to “60 volts”

10. Section 690.71 (B) is a DC system with a threshold of 50 volts. Revise the text from “50 volts” to “60 volts DC”.

11. Article 720 Circuits and Equipment Operating at Less Than 50 Volts covers both AC and DC systems. To correlate the Title has been changed to “50 Volts AC/60 Volts DC”. The Scope 720.1 and section 720.11 have been modified to clarify that this Article applies to both systems with the corresponding voltage.

Related Item

Public Input No. 3681-NFPA 70-2014 [Global Input]

Submitter Information Verification

Submitter Full Name: Lawrence Ayer

Organization: Biz Com Electric, Inc.

Affilliation: IEC

Street Address:

City:

State:

Zip:

Submittal Date: Wed Sep 23 14:39:50 EDT 2015


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Public Comment No. 462-NFPA 70-2015 [ Section No. 300.4 ]

300.4 Protection Against Physical Damage.

Where subject to physical damage, conductors, raceways, and cables shall be protected.

(A) Cables and Raceways Through Wood Members.

(1) Bored Holes.

In both exposed and concealed locations, where a cable- or raceway-type wiring method is installed through bored holes in

joists, rafters, or wood members, holes shall be bored so that the edge of the hole is not less than 32 mm (1 1 ⁄ 4 in.) from thenearest edge of the wood member. Where this distance cannot be maintained, the cable or raceway shall be protected frompenetration by screws or nails by a listed and marked steel plate(s) or bushing(s)

, at least 1.6 mm ( 1 ⁄ 16 in.) thick, and

of appropriate length and width installed to cover the area of the wiring.

Exception No. 1: Steel plates shall not be required to protect rigid metal conduit, intermediate metal conduit, rigidnonmetallic conduit, or electrical metallic tubing.

Exception No. 2: A listed and marked steel plate less than 1.6 mm ( 1 ⁄ 16 in.) thick that provides equal or better protectionagainst nail or screw penetration shall be permitted.

Informational Note: ANSI/UL 2239 defines requirements for listed steel bushings.

(2) Notches in Wood.

Where there is no objection because of weakening the building structure, in both exposed and concealed locations, cables orraceways shall be permitted to be laid in notches in wood studs, joists, rafters, or other wood members where the cable or

raceway at those points is protected against nails or screws by a listed and marked steel plate at least 1.6 mm ( 1 ⁄ 16 in.)thick, and of appropriate length and width, installed to cover the area of the wiring. The steel plate shall be installed before thebuilding finish is applied.

Exception No. 1: Steel plates shall not be required to protect rigid metal conduit, intermediate metal conduit, rigid nonmetallicconduit, or electrical metallic tubing. Exception No. 2: A listed and marked steel plate less than 1.6 mm

(

1 ⁄ 16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.

( B) Nonmetallic-Sheathed Cables and Electrical Nonmetallic Tubing Through Metal Framing Members.

(1) Nonmetallic-Sheathed Cable.

In both exposed and concealed locations where nonmetallic-sheathed cables pass through either factory- or field-punched, cut,or drilled slots or holes in metal members, the cable shall be protected by listed bushings or listed grommets covering all metaledges that are securely fastened in the opening prior to installation of the cable.

(2) Nonmetallic-Sheathed Cable and Electrical Nonmetallic Tubing.

Where nails or screws are likely to penetrate nonmetallic-sheathed cable or electrical nonmetallic tubing, a listed and marked

steel sleeve, steel plate, or steel clip not less than 1.6 mm ( 1 ⁄ 16 in.) in thickness shall be used to protect the cable ortubing. Exception: A listed and marked steel plate less than 1.6 mm

(


( C) Cables Through Spaces Behind Panels Designed to Allow Access.

Cables or raceway-type wiring methods, installed behind panels designed to allow access, shall be supported according to theirapplicable articles.


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(D) Cables and Raceways Parallel to Framing Members and Furring Strips.

In both exposed and concealed locations, where a cable- or raceway-type wiring method is installed parallel to framingmembers, such as joists, rafters, or studs, or is installed parallel to furring strips, the cable or raceway shall be installed andsupported so that the nearest outside surface of the cable or raceway is not less than 32 mm (1 1⁄4 in.) from the nearest edge ofthe framing member or furring strips where nails or screws are likely to penetrate. Where this distance cannot be maintained,the cable or raceway shall be protected from penetration by nails or screws by a listed and marked steel plate, sleeve, or

equivalent at least 1 .6 mm ( 1 ⁄ 16 in.) thick.

Exception No. 1: Steel plates, sleeves, or the equivalent shall not be required to protect rigid metal conduit, intermediate metalconduit, rigid nonmetallic conduit, or electrical metallic tubing.

Exception No. 2: For concealed work in finished buildings, or finished panels for prefabricated buildings where suchsupporting is impracticable, it shall be permissible to fish the cables between access points. Exception No. 3: A listed andmarked steel plate less than 1.6 mm

(


( E) Cables, Raceways, or Boxes Installed in or Under Roof Decking.

A cable, raceway, or box, installed in exposed or concealed locations under metal-corrugated sheet roof decking, shall beinstalled and supported so there is not less than 38 mm (1 1⁄2 in.) measured from the lowest surface of the roof decking to thetop of the cable, raceway, or box. A cable, raceway, or box shall not be installed in concealed locations in metal-corrugated,sheet decking–type roof.

Informational Note: Roof decking material is often repaired or replaced after the initial raceway or cabling and roofinginstallation and may be penetrated by the screws or other mechanical devices designed to provide “hold down” strengthof the waterproof membrane or roof insulating material.

Exception: Rigid metal conduit and intermediate metal conduit shall not be required to comply with 300.4(E) .

(F) Cables and Raceways Installed in Shallow Grooves.

Cable- or raceway-type wiring methods installed in a groove, to be covered by wallboard, siding, paneling, carpeting, or similar

finish, shall be protected by 1.6 mm ( 1 ⁄ 16 in.) thick a listed and marked steel plate, sleeve, or equivalent or by not less than32-mm (1 1⁄4 -in.) free space for the full length of the groove in which the cable or raceway is installed.

Exception No. 1: Steel plates, sleeves, or the equivalent shall not be required to protect rigid metal conduit, intermediate metalconduit, rigid nonmetallic conduit, or electrical metallic tubing. Exception No. 2: A listed and marked steel plate less than 1.6mm

(


( G) Insulated Fittings.

Where raceways contain 4 AWG or larger insulated circuit conductors, and these conductors enter a cabinet, a box, anenclosure, or a raceway, the conductors shall be protected by an identified fitting providing a smoothly rounded insulatingsurface, unless the conductors are separated from the fitting or raceway by identified insulating material that is securelyfastened in place.

Exception: Where threaded hubs or bosses that are an integral part of a cabinet, box, enclosure, or raceway provide asmoothly rounded or flared entry for conductors.

Conduit bushings constructed wholly of insulating material shall not be used to secure a fitting or raceway. The insulating fittingor insulating material shall have a temperature rating not less than the insulation temperature rating of the installed conductors.

(H) Structural Joints.

A listed expansion/deflection fitting or other approved means shall be used where a raceway crosses a structural joint intendedfor expansion, contraction or deflection, used in buildings, bridges, parking garages, or other structures.


The Panel 3 response to PI 1592 noted a lack of evaluation of protector plates from several manufacturers. This has now been addressed. Video is accessible at the link which demonstrates that several NEC-compliant protector plates from different manufacturers do not stop penetration from self-drilling drywall screws.https://erico.box.com/s/0uvbl0bqapvj25jht3tazlgayqm6lx7rIf the NEC does not require listing of all protector plates, then there is a safety issue that is not being addressed. Self-drilling drywall screws easily penetrate 1/16” thick protector plates made from low carbon steel (like they all are). Please watch the linked video which demonstrates that NEC-compliant protector plates from several manufacturers clearly exhibit poor resistance to penetration. As it stands today, STP2239 and CANENA withdrew the proposal which had already been accepted to define testing requirements for protector plates, likely due to pressure from specific manufacturers. Without a listing requirement in the NEC, there is no motivation for STP2239 to follow through with defining evaluation requirements for all protector plates.Note that in the video demonstration there is no drywall. Without drywall providing support to the drywall screw, it requires the installer to use less force to prevent the screw from skipping off the protector plate. Therefore, if drywall was present, the screws would penetrate in even less time.


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Related Item

Public Input No. 1592-NFPA 70-2014 [Section No. 300.4]


Submitter Full Name: ROBERT JENSEN

Organization: DBI-TELECOMMUNICATION INFRASTR

Affilliation: BICSI

Street Address:

City:

State:

Zip:

Submittal Date: Fri Aug 28 16:07:34 EDT 2015


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Public Comment No. 1028-NFPA 70-2015 [ Section No. 300.4 [Excluding any Sub-Sections] ]

Where subject to physical damage, conductors, raceways, and cables shall be protected.

Informational Note: Physical damage is not expected to occur to concealed wiring methods during normal

building operation. Minor damage to a raceway, cable armor or cable insulation does not necessarily

violate the integrity of either the contained conductors or the conductors’ insulation.


This informational note provides guidance regarding wiring integrity and physical damage. There are many places in the NEC that refer to "physical damage", and concealment behind walls in accordance with installation requirements in the NEC protects wiring from physical damage during normal building operation. Since we have no definition of "physical damage" in the NEC and there have been instances of inspectors rejecting installations with minor scrapes on wiring methods, the second sentence provides guidance for those cases.

The panel stated that "The addition of this Informational Note does not provide any valuable information to the user to determine violation of integrity of the conductors or conductor insulation where damage to the raceway has occurred." This informational note is not intended to provide such information. It is intended to indicate to users of the code that minor blemishes on a wiring method do not necessarily mean that the wiring method must be replaced or that it is incapable of functioning. To clarify that, the word "Visible" was replaced with "Minor" as the first word in the second sentence.

Related Item

Public Input No. 4306-NFPA 70-2014 [Section No. 300.4 [Excluding any Sub-Sections]]


Submitter Full Name: Christel Hunter

Organization: General Cable

Street Address:

City:

State:

Zip:



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Public Comment No. 1165-NFPA 70-2015 [ Section No. 300.4(B) ]

(B) Nonmetallic-Sheathed Cables and Electrical Nonmetallic Tubing Through Metal Framing Members.

(1) Nonmetallic-Sheathed Cable.

In both exposed and concealed locations where nonmetallic-sheathed cables pass through either factory- or field-punched, cut,or drilled slots or holes in metal members, the cable shall be protected by listed bushings or listed grommets covering all metaledges that are securely fastened in the opening prior to installation of the cable.

(2) Nonmetallic-Sheathed Cable Cables and Electrical Nonmetallic Tubing.

Where nails or screws are likely to penetrate nonmetallic-sheathed cable or electrical nonmetallic tubing, a steel sleeve, steelplate, or steel clip not less than 1.6 mm ( 1⁄16 in.) in thickness shall be used to protect the cable or tubing.

Exception: A listed and marked steel plate less than 1.6 mm ( 1⁄16 in.) thick that provides equal or better protection against nailor screw penetration shall be permitted.


What generated the original input was the very common use of metallic "shallow studs' (which are considerably narrower than a standard 3.5" stud) these also have factory field punched holes but do not offer the same protection as a standard 3.5" metal stud. This same code article requires protection for MC cable when running parallel where 11/4" is not met. The same possible short circuit would occur when running horizontal in shallow studs because maintaining 11/4" is not possible. I entered this same proposal in 2014 and the panel stated that it was already required in 300.4. Please look closely and reconsider for at least consistency or remove the protection requirement when running parallel

Related Item

Public Input No. 3789-NFPA 70-2014 [Section No. 300.4(B)]


Submitter Full Name: james dorsey

Organization: Douglas county

Street Address:

City:

State:

Zip:



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Direct-buried cable or conduit or other raceways shall be installed to meet the minimum cover requirements of Table 300.5.

Table 300.5 Minimum Cover Requirements, 0 to 1000 Volts, Nominal, Burial in Millimeters (Inches)

Type of Wiring Method or Circuit

Location of WiringMethod or Circuit

Column 1

Direct BurialCables or

Conductors

Column 2

Rigid MetalConduit or

IntermediateMetal Conduit

Column 3

NonmetallicRaceways Listedfor Direct Burial

Without ConcreteEncasement orOther Approved

Raceways

Column 4

Residential BranchCircuits Rated 120Volts or Less withGFCI Protectionand MaximumOvercurrent

Protection of 20Amperes

Column 5

Circuits for Controlof Irrigation and

Landscape LightingLimited to Not MoreThan 30 Volts andInstalled with Type

UF or in OtherIdentified Cable or

Raceway

mm in. mm in. mm in. mm in. mm in.

All locations notspecified below

600 24 150 6 450 18 300 12 150 a 6 a

In trench below 50 mm(2 in.) thick concrete orequivalent

450 18 150 6 300 12 150 6 150 6

Under a building ,provided the slab ongrade is not beingused as a parking lot

0 0 0 0 0 0 0 0 0 0

(in raceway orType MC or

Type MI cableidentified fordirect burial)

(in raceway or TypeMC or Type MI cableidentified for direct

burial)

(in raceway or TypeMC or Type MI cableidentified for direct

burial)

Under minimum of 102mm (4 in.) thickconcrete exterior slabwith no vehicular trafficand the slab extendingnot less than 152 mm(6 in.) beyond theundergroundinstallation

450 18 100 4 100 4

150 6 150 6

(direct burial)(direct burial)

100 4 100 4

(in raceway)(in raceway)

Under streets,highways, roads,alleys, driveways, andparking lots

600 24 600 24 600 24 600 24 600 24

One- and two-familydwelling drivewaysand outdoor parkingareas, and used onlyfor dwelling-relatedpurposes

450 18 450 18 450 18 300 12 450 18

In or under airportrunways, includingadjacent areas wheretrespassing prohibited

450 18 450 18 450 18 450 18 450 18

aA lesser depth shall be permitted where specified in the installation instructions of a listed low voltage lighting system.

Notes:

1. Cover is defined as the shortest distance in millimeters (inches) measured between a point on the top surface of any direct-buried conductor, cable, conduit, or other raceway and the top surface of finished grade, concrete, or similar cover.

2. Raceways approved for burial only where concrete encased shall require concrete envelope not less than 50 mm (2 in.) thick.

3. Lesser depths shall be permitted where cables and conductors rise for terminations or splices or where access is otherwiserequired.

4. Where one of the wiring method types listed in Columns 1 through 3 is used for one of the circuit types in Columns 4 and 5,the shallowest depth of burial shall be permitted.

5. Where solid rock prevents compliance with the cover depths specified in this table, the wiring shall be installed in a metalraceway, or a nonmetallic raceway permitted for direct burial. The raceways shall be covered by a minimum of 50 mm (2 in.) of


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kshea

Text Box

Public Comment No. 1425-NFPA 70-2015 [ Section No. 300.5(A) ]

concrete extending down to rock.


Webster's Definition of a "parking lot"an area, usually divided into individual spaces, intended for parking motor vehicles. This additional language trying to declare that it is still a parking lot was rejected with the panel statement declaring that 24" are required in some cases but not all depending on the construction of the slab. I reach out to the inspector members and try and explain to a contractor that Yes we are under a building but 24" is required where on the 2nd level of parking there is only 6" of concrete and it is allowed to place conduits in it. Adding this language or an informational note would allow for consistency. Is it under a building or is it under a parking lot??? thank you for the consideration

Related Item

Public Input No. 2923-NFPA 70-2014 [Section No. 300.5(A)]


Submitter Full Name: james dorsey

Organization: Douglas county

Street Address:

City:

State:

Zip:

Submittal Date: Fri Sep 25 10:57:58 EDT 2015


512 of 2079 10/1/2015 11:02 AM

Public Comment No. 1219-NFPA 70-2015 [ Section No. 300.5(D)(3) ]

(3) Service Conductors.

Underground service conductors and feeders that are not encased in concrete and that are buried 450 mm (18 in.) or morebelow grade shall have their location identified by a warning ribbon that is placed in the trench at least 300 mm (12 in.) abovethe underground installation.


Please reconsider the action taken at the public input stage. This is a potential safety issue for electrical workers.

Note that the public comment restricts this to feeders from the original public input.

The NEC Handbook states that this ribbon is not required for feeders because, unlike service conductors, these have short circuit and overload protection. Throughout the NEC the code goes to great lengths to provide physical protection of electrical conductors so it’s difficult to find logic with the reason given in the NEC Handbook. A warning ribbon installed at the proper height above the feeders provides a higher degree of safety for electrical workers. It also can be a great value for so little cost considering repairs and down time in the event these conductors are hit.It is a sensible precaution in preventing ground faults or short circuits.

Related Item

Public Input No. 1133-NFPA 70-2014 [Section No. 300.5(D)(3)]


Submitter Full Name: Marcelo Hirschler

Organization: GBH International

Street Address:

City:

State:

Zip:

Submittal Date: Thu Sep 24 13:39:35 EDT 2015


513 of 2079 10/1/2015 11:02 AM



Underground service conductors and feeders that are not encased in concrete and that are buried 450 mm (18 in.) or morebelow grade shall have their location identified by a warning ribbon that is placed in the trench at least 300 mm (12 in.) abovethe underground installation.


This language would provide a very low cost to an installation that could save major costs to equipment that may be damaged by digging into underground feeders. This minimum installation provides a greater degree of safety to property and electrical equipment.

Related Item



Submitter Full Name: Susan Scearce

Organization: City of Humboldt, TN

Street Address:

City:

State:

Zip:



514 of 2079 10/1/2015 11:02 AM



Underground service conductors and feeder conductors that are not encased in concrete and that are buried 450 mm (18 in.)or more below grade shall have their location identified by a warning ribbon that is placed in the trench at least 300 mm (12 in.)above the underground installation.


As an electrical inspector on a military base, we constantly see underground installations damaged by new construction cutting into existing raceways/cables. We almost NEVER see that damage occur when the ribbon is installed, only on existing installations where the ribbon is not required. Frankly, the cost of the ribbon is negligible and the benefit of not damaging the existing circuits would far outweigh the minimal cost. We have a LOT of raceways underground around here. Digging is almost always an adventure, even though we "locate" the existing stuff before we start. That science is helpful, but by no means absolute. I'd like to see the practice of installing the ribbon applied to EVERY underground installation (18 inches and deeper), including branch ciruits, but for now, I'm suggesting that we add feeders to the requirement.

Related Item



Submitter Full Name: ED SITTON

Organization: FT CAMPBELL KY DPW

Affilliation: Electrical Inspector

Street Address:

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State:

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515 of 2079 10/1/2015 11:02 AM


(4) Enclosure or Raceway Damage.

Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in steel (not aluminum)electrical metallic tubing, rigid metal conduit, intermediate metal conduit, RTRC-XW, Schedule 80 PVC conduit, or equivalent.


Aluminum EMT has a much lower crush/bend rating than steel EMT, and therefore should not be considered as a viable method of protection of conductors against damage.

Related Item

First Revision No. 606-NFPA 70-2015 [Section No. 300.5(D)(4)]


Submitter Full Name: WILLIAM NOACK

Organization: WLN ENTERPRISES

Street Address:

City:

State:

Zip:

Submittal Date: Tue Sep 22 16:49:40 EDT 2015


516 of 2079 10/1/2015 11:02 AM


(B) Expansion Fittings.

Raceways shall be provided with expansion fittings or expansion/deflection fittings where necessary to compensate for thermalexpansion and contraction.

Informational Note: Table 352.44 and Table 355.44 provide the expansion information for polyvinyl chloride (PVC) andfor reinforced thermosetting resin conduit (RTRC), respectively. A nominal number for steel conduit can be determined bymultiplying the expansion length in Table 352.44 by 0.20. The coefficient of expansion for steel electrical metallic tubing,

intermediate metal conduit, and rigid metal conduit is 1.170 × 10-5 (0.0000117 mm per mm of conduit for each °C in

temperature change) [0.650 × 10-5 (0.0000065 in. per inch of conduit for each °F in temperature change)].

A nominal number for aluminum conduit and aluminum electrical metallic tubing can be determined by multiplying theexpansion length in Table 352.44 by 0.40. The coefficient of expansion for aluminum electrical metallic tubing and

aluminum rigid metal conduit is 2.34 × 10-5 (0.0000234 mm per mm of conduit for each °C in temperature change) [1.30

× 10-5 (0.000013 in. per inch of conduit for each °F in temperature change)].


Reconsider Resolved Public Input #1899 and revise 300.7(B). A standard expansion fitting works when the raceways is installed a straight axial alignment whereas the expansion/deflection fitting accommodates for the raceway’s thermal expansion or contraction when the raceways are off-set or misaligned. The proposed language makes it clear to inspectors, designers and contractors that expansion/deflection fittings are acceptable to be used with a raceways to address thermal expansion and contraction.

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Submitter Full Name: DAVID KENDALL

Organization: THOMAS BETTS CORPORATION

Street Address:

City:

State:

Zip:

Submittal Date: Wed Jul 01 09:19:41 EDT 2015


517 of 2079 10/1/2015 11:02 AM


300.9 Raceways in Wet Locations Abovegrade.

Where raceways are installed in wet locations abovegrade above grade , the interior of these raceways shall be considered tobe a wet location unless all fittings and enclosures are listed watertight . Insulated conductors and cables installed in racewaysin wet locations abovegrade above grade without all fittings and enclosures listed watertight shall comply with 310.10(C).


I submitted PI 627 and PI 628 and both PIs were resolved. I read the committee statement and wanted to submit a public comment however the system will not let me relate this public comment to either of my PIs. Hopefully this will work and CMP 3 will be able to respond to my public comment. This comment applies to 300.9 and 300.38.

When I submitted PI 627 and PI 628 I used the term "raintight" and that was an error. I should have used the term "watertight".

Sections 300.9 and 300.38 as currently written do not recognize material listed as "watertight". Installers are required to use fittings and enclosures listed for use in wet locations when installing raceway systems on the exterior of a building. The UL White Book states "For equipment designated watertight the equipment is so constructed that water does not enter the enclosure when subjected to a stream of water." The definition in Article 100 for watertight is “constructed so that moisture will not enter the enclosure under specified test conditions.” The NEC must recognize that a listed product will perform to the standard for which it was tested. Throughout the NEC are listing requirements and AHJs put their faith in qualified electrical testing laboratories that the listed products will perform as tested. The interior of raceways installed in wet locations above grade utilizing listed watertight fittings and enclosures cannot be considered a wet location.

Related Item



Submitter Full Name: ROBERT JONES

Organization: IEC Texas Gulf Coast

Street Address:

City:

State:

Zip:



518 of 2079 10/1/2015 11:02 AM


300.11 Securing and Supporting.

(A) Secured in Place.

Raceways, cable assemblies, boxes, cabinets, and fittings shall be securely fastened in place.

(B) Wiring Systems Installed Above Suspended Ceilings.

Support wires that do not provide secure support shall not be permitted as the sole support. Support wires and associatedfittings that provide secure support and that are installed in addition to the ceiling grid support wires shall be permitted as thesole support. Where independent support wires are used, they shall be secured at both ends. Cables and raceways shall not besupported by ceiling grids.

(1) Fire-Rated Assemblies.

Wiring located within the cavity of a fire-rated floor–ceiling or roof–ceiling assembly shall not be secured to, or supported by, theceiling assembly, including the ceiling support wires. An independent means of secure support shall be provided and shall bepermitted to be attached to the assembly. Where independent support wires are used, they shall be distinguishable by color,tagging, or other effective means from those that are part of the fire-rated design.

Exception: The ceiling support system shall be permitted to support wiring and equipment that have been tested as part of thefire-rated assembly.

Informational Note: One method of determining fire rating is testing in accordance with ANSI/ASTM E119-2014, Methodfor Fire Tests of Building Construction and Materials.

(2) Non–Fire-Rated Assemblies.

Wiring located within the cavity of a non–fire-rated floor–ceiling or roof–ceiling assembly shall not be secured to, or supportedby, the ceiling assembly, including the ceiling support wires. An independent means of secure support shall be provided andshall be permitted to be attached to the assembly. Where independent support wires are used, they shall be distinguishable bycolor, tagging, or other effective means.

Exception: The ceiling support system shall be permitted to support branch-circuit wiring and associated equipment whereinstalled in accordance with the ceiling system manufacturer’s instructions.

(C) Raceways Used as Means of Support.

Raceways shall be used only as a means of support for other raceways, cables, or nonelectrical equipment under any of thefollowing conditions:

(1) Where the raceway or means of support is identified as a means of support

(2) Where the raceway contains power supply conductors for electrically controlled equipment and is used to support Class 2circuit conductors or cables that are solely for the purpose of connection to the equipment control circuits

(3) Where the raceway is used to support boxes or conduit bodies in accordance with 314.23 or to support luminaires inaccordance with 410.36(E)

(D) Cables Not Used as Means of Support.

Cable wiring methods shall not be used as a means of support for other cables, raceways, or nonelectrical equipment.

(E) Metallic Means of Support Above Egress

Metallic means of support for flexible conduit and conductors shall be used in spaces above egress, which includes doorways,hallways, stairways, corridors, passageways, lobbies, landings, and equivalent spaces.

Informational note: Nonmetallic supports exhibit significant weakening and failure during fires which can affect the safety ofoccupants and emergency personnel entering and exiting buildings due to entanglement in fallen cable.


Emergency responders and building occupant safety is at risk during building fires because people can become entangled and trapped in cabling which has fallen out of molten or failing plastic supports/raceway. Even if people can free themselves from fallen cabling, this takes time which is otherwise needed to exit the building or fulfill the objectives of emergency personnel. The frequency of emergency responders becoming trapped in fallen cabling has become so common that firefighters have created and publicly distributed training videos on how to escape in these situations(http://www.fireengineering.com/topics/m/video/36928837/the-quick-release-method.htm?q=cable+entanglement) [1]. Additionally, the Greater Tucson Fire Foundation raised financial support in 2011 to purchase cable cutters for hundreds of Tucson, Arizona firefighters so that they are equipped to deal with cable entanglement [2].

The ideal scope of this requirement should include all wiring methods which are susceptible to falling during a fire. This includes insulated conductors, flexible metal conduit, and nonmetallic raceways with plastic supports. It should include power conductors, signaling conductors, fire alarm cables, and communications circuits. Although CMP 3 can only address a portion of the relevant scope,


519 of 2079 10/1/2015 11:02 AM

I urge you to address what you can within the scope of 300.11 by accepting the intent of this proposal.

Since CMP 3 review of Public Input 4649 in January 2015, BS 7671 (UK Wiring Regulations) was published with Amendment 3 which requires metal supports for cables installed in escape routes [3, 4] and went into effect on July 1, 2015. This requirement is no longer limited only to fire alarm systems, but now includes all wiring methods.

Bibliography:[1] Fire Engineering Training Minutes. Presented by Mike Ciampo, Fire Department of New York. Accessed 9/25/15. http://www.fireengineering.com/topics/m/video/36928837/the-quick-release-method.htm?q=cable+entanglement

[2] “Rescue Tools” Greater Tucson Fire Foundation. Accessed 9/25/15. http://www.tucsonfirefoundation.com/health-and-wellbeing/

[3] “Fire resisting supports in escape routes” Accessed 9/25/15. http://electrical.theiet.org/wiring-matters/54/escape-routes/index.cfm

[4] “Amendment 3 to BS 6761 tackles ‘cable entanglement’ deaths” Accessed 9/25/15. http://www.voltimum.co.uk/articles/amendment-3-bs-7671-tackles-cable-entanglement-deaths

Related Public Comments for This Document

Related Comment Relationship

Public Comment No. 1677-NFPA 70-2015 [Section No. 725.24]

Public Comment No. 1685-NFPA 70-2015 [Section No. 760.24(A)]

Related Item

Public Input No. 4649-NFPA 70-2014 [New Section after 300.11]


Submitter Full Name: WARD JUDSON

Organization: ERICO INTERNATIONAL CORP

Street Address:

City:

State:

Zip:



520 of 2079 10/1/2015 11:02 AM

Public Comment No. 122-NFPA 70-2015 [ Section No. 300.11(B)(1) ]




Informational Note: One method of determining fire rating is testing in accordance with ANSI/ ASTM E119-2014 2015 ,Method for Fire Tests of Building Construction and Materials.


Referenced correct SDO and updated edition.

Related Item

First Revision No. 610-NFPA 70-2015 [Section No. 300.11]


Submitter Full Name: Aaron Adamczyk

Organization: [ Not Specified ]

Street Address:

City:

State:

Zip:

Submittal Date: Mon Jul 06 11:18:12 EDT 2015


521 of 2079 10/1/2015 11:02 AM

Public Comment No. 801-NFPA 70-2015 [ Section No. 300.11(B)(1) ]




Informational Note: One method of determining fire rating is testing in accordance with ANSI/ASTM E119-2014 2015 ,Method for Fire Tests of Building Construction and Materials.


Standard date update



Public Comment No. 800-NFPA 70-2015 [Section No. 110.31(A)(5)]

Public Comment No. 803-NFPA 70-2015 [Section No. 450.21(B)]


Related Item

Public Input No. 1728-NFPA 70-2014 [Section No. 110.31(A)(5)]




Street Address:

City:

State:

Zip:

Submittal Date: Sun Sep 20 19:38:10 EDT 2015


522 of 2079 10/1/2015 11:02 AM


300.12 Mechanical Continuity — Raceways and Cables.

(A) Raceways and Cables. Raceways , cable armors, and cable sheaths shall be continuous between cabinets, boxes,fittings, or other enclosures or outlets.

Exception No. 1: Short sections of raceways used to provide support or protection of cable assemblies from physical damageshall not be required to be mechanically continuous.

Exception No. 2: Raceways and cables installed into the bottom of open bottom equipment, such as switchboards, motorcontrol centers, and floor or pad-mounted transformers, shall not be required to be mechanically secured to the equipment.

(B) Reducing Washers. Metal reducing washers are permitted to be used with metal enclosures having a minimumthickness of 0.053 in. for non-service conductors only. Nonconductive coatings (such as paint, lacquer, and emamel)on metallic enclosures shall be removed from contact surfaces to ensure good electrical continuity as required by250.12 Reducing washers are permitted to be installed in enclosures provided with concentric or eccentric knockouts,only after all of the concentric and eccentric rings have been removed.

Exception: Those enclosures containing concentric and eccentric knockouts that have been certifed for bonding purposesshall be permitted to be used with reducing washers without all knockouts being removed.


Reducing washers are commonly used in electrical installations and their installation should be covered in the NEC. At the present time the limited installation rules are in the UL White book under Outlet Bushings and Fittings (QCRV). This rule should be located here in Article 300 as the use of reducing washers is common to every cable and conduit wiring method that is connected to an enclosure as covered throughout the remainder of Chapter 3. Other articles such as Article 250 deal with the installation of reducing washers in a limited way.The general requirement should be here in Article 300.

Related Item



Submitter Full Name: Phil Simmons

Organization: Simmons Electrical Services

Street Address:

City:

State:

Zip:



523 of 2079 10/1/2015 11:02 AM


(A) Spacing Intervals — Maximum.

Conductors in vertical raceways shall be supported if the vertical rise exceeds the values in Table 300.19(A). At least onesupport method shall be provided for each conductor or cable assembly at the top of the vertical raceway or as close to the topas practical. Intermediate supports shall be provided as necessary to limit supported conductor lengths to not greater than thosevalues specified in Table 300.19(A).

Exception: Steel wire armor cable shall be supported at the top of the riser with a cable support that clamps the steel wirearmor. A safety device shall be permitted at the lower end of the riser to hold the cable in the event there is slippage of thecable in the wire-armored cable support. Additional wedge-type supports shall be permitted to relieve the strain on theequipment terminals caused by expansion of the cable under load.

Table 300.19(A) Spacings for Conductor Supports

Conductors

Conductor Size Support of Conductors in Vertical Raceways

Aluminum or

Copper-Clad

Aluminum

Copper

m ft m ft

18 AWG through 8 AWG Not greater than 30 100 30 100

6 AWG through 1/0 AWG Not greater than 60 200 30 100

2/0 AWG through 4/0 AWG Not greater than 55 180 25 80

Over 4/0 AWG through 350 kcmil Not greater than 41 135 18 60

Over 350 kcmil through 500 kcmil Not greater than 36 120 15 50

Over 500 kcmil through 750 kcmil Not greater than 28 95 12 40

Over 750 kcmil Not greater than 26 85 11 35


A cable assembly is multiple conductors grouped together (usually by plexing) without an overall covering. Deleting "cable assembly" from the revised language ensures that each individual conductor is supported at the top of a vertical raceway, which can be accomplished by gland type fittings or other identified means of support.

Related Item

First Revision No. 612-NFPA 70-2015 [Section No. 300.19(A)]


Submitter Full Name: Christel Hunter

Organization: General Cable

Street Address:

City:

State:

Zip:



524 of 2079 10/1/2015 11:02 AM


(B) Individual Conductors.

Where a single conductor carrying alternating current passes through metal with magnetic properties, the inductive effect shallbe minimized by (1) cutting slots in the metal between the individual holes through which the individual conductors pass or (2)passing all the conductors in the circuit through an insulating wall sufficiently large for all of the conductors of the circuit.

Exception: In the case of circuits supplying vacuum or electric-discharge lighting systems , constant current regulator outputsused for airfield lighting series circuits, or signs or X-ray apparatus, the currents carried by the conductors are so small thatthe inductive heating effect can be ignored where these conductors are placed in metal enclosures or pass through metal.

Informational Note: Because aluminum is not a magnetic metal, there will be no heating due to hysteresis; however,induced currents will be present. They will not be of sufficient magnitude to require grouping of conductors or specialtreatment in passing conductors through aluminum wall sections.


The modification to the exception is necessary due to the way the series circuit conductors are routed through the light bases on the airfield.

A typical series circuit installation will have one leg of the circuit enter the galvanized steel light base on one side (let’s say at 0 degrees), this conductor will connect to the isolation transformer. The other leg of the isolation transformer will connect to another conductor. This second conductor will exit the galvanized steel light base on the opposite side of the light base (at 180 degrees). The primary conductor enters and exits the galvanized steel enclosure (light base) through separate/distinct openings. No slots are cut between the openings. No effort or attempt is made to address inductive heating.



Public Comment No. 579-NFPA 70-2015 [New Section after392.10(D)]

additional explaination of typical airfield lighting seriescircuit.

Related Item

Public Input No. 2739-NFPA 70-2014 [New Section after 392.10(D)]


Submitter Full Name: Carl Johnson II

Organization: AVCON, Inc.

Affilliation: none

Street Address:

City:

State:

Zip:



525 of 2079 10/1/2015 11:02 AM


(B) Ducts Specifically Fabricated for Environmental Air.

Equipment, devices, and the wiring methods specified in this section shall be permitted within such ducts only if necessary forthe direct action upon, or sensing of, the contained air. Where equipment or devices are installed and illumination is necessaryto facilitate maintenance and repair, enclosed gasketed-type luminaires shall be permitted.

Only wiring methods consisting of Type MI cable without an overall nonmetallic covering, Type MC cable employing a smoothor corrugated impervious metal sheath without an overall nonmetallic covering, electrical metallic tubing, flexible metallictubing, intermediate metal conduit, or rigid metal conduit without an overall nonmetallic covering shall be installed in ductsspecifically fabricated to transport environmental air. Flexible metal conduit shall be permitted, in lengths not to exceed 1.2 m (4ft), to connect physically adjustable equipment and devices permitted to be in these fabricated ducts. The connectors used withflexible metal conduit shall effectively close any openings in the connection.

Exception: Wiring methods and cabling systems, listed for use in other spaces used for environmental air (plenums), shall bepermitted to be installed in ducts specifically fabricated for environmental air-handling purposes under the followingconditions:

(1) The wiring methods or cabling systems shall be permitted only if necessary to connect to equipment or devicesassociated with the direct action upon or sensing of the contained air, and

(2) The total length of such wiring methods or cabling systems shall not exceed 1.2 m (4 ft).


The Correlating Committee also directs that FR 3309 be referred to Panel 3 for comment. in regards to the limited distance in 300.22(B).

Related Item

First Revision No. 3309-NFPA 70-2015 [Section No. 640.3(B)]


Submitter Full Name: CC on NEC-AAC

Organization: NFPA

Street Address:

City:

State:

Zip:

Submittal Date: Mon Sep 28 15:53:32 EDT 2015


526 of 2079 10/1/2015 11:02 AM

Public Comment No. 163-NFPA 70-2015 [ Section No. 300.22(C)(3) ]

(3) Equipment.

Electrical equipment with a metal enclosure, or electrical equipment with a nonmetallic enclosure listed for use within anair-handling space and having low smoke and heat release properties, and associated wiring material suitable for the ambienttemperature shall be permitted to be installed in such other space unless prohibited elsewhere in this Code.

Informational Note: One method to determine low smoke and heat release properties is that the equipment exhibits amaximum peak optical density of 0.50 or less, an average optical density of 0.15 or less, and a peak heat release rate of100kW or less when tested in accordance with ANSI/ UL 2043-2008 2013 , Fire Test for Heat and Visible SmokeRelease for Discrete Products and Their Accessories Installed in Air-Handling Spaces.

Exception: Integral fan systems shall be permitted where specifically identified for use within an air-handling space.


Referenced current edition of UL 2043.

Related Item

First Revision No. 645-NFPA 70-2015 [Section No. 300.22(C)(3)]



Submitter Full Name: Aaron Adamczyk

Organization: [ Not Specified ]

Street Address:

City:

State:

Zip:



527 of 2079 10/1/2015 11:02 AM


300.37 Aboveground Wiring Methods.

Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in electrical metallic tubing, inRTRC and PVC conduit, in cable trays, in auxiliary gutters, as busways, as cablebus, in other identified raceways, or asexposed runs of metal-clad cable suitable for the use and purpose. In locations accessible to qualified persons only, exposedruns of Type MV cables, exposed runs of FAA L-824 cables , bare conductors, and bare busbars shall also be permitted.Busbars shall be permitted to be either copper or aluminum.

Informational Note: Federal Aviation Administration (FAA) Advisory Circulars (ACs) provide additional practices and methods for airportlighting.

Additional Proposed Changes

File Name Description Approved

DSCN2209.JPG

Photo of a L-829 constant current regulator (CCR) with output L-824 cables routed in free air to underground duct run powering airfield lighting series circuit. Exposed L-824 cables have L-823 connectors installed to facilitate the quick replacement of the power source. An adjacent CCR can be quickly and easily connected to the field circuit.

DSCN2188.JPGPhoto of FAA owned Runway Visual Range cabinet utilizing exposed runs of L-824 cable. The FAA also allows exposed runs of L-824 on FAA owned equipment.


I strongly support PI 2762 and request the CMP reconsider the PI.

Based upon my research, prior to 2004 and the first issue of FAA Advisory Circular 150/5340-30 there was no FAA prohibition to the practice of installing L-824 cable in free air within the airfield lighting vault. It appears the FAA requirements were revised to comply with the NEC at that time.

Historically many airfield lighting vaults were powered by 4,160 volt and 2,400 volt systems. Many of these installations were powered by distribution cable mounted on insulators attached to the airfield lighting vault walls. A cable tap protected by a fused cut-out powered the constant current regulator. Thankfully, this practice was also eliminated by the new AC in 2004.

The effort to bring harmony between the FAA Advisory Circulars and the NEC created an unexpected consequence.

The electrical characteristics of an airfield lighting series (current) circuit are significantly different than those of a conventional parallel (voltage) circuit we are all familiar with.

The practice of routing L-824 cable in free air (in locations accessible to qualified persons only) has been used safely and successfully throughout the industry to expedite troubleshooting and repair of airfield lighting circuits.

Related Item



Submitter Full Name: CARL JOHNSON II

Organization: AVCON INC

Affilliation: none

Street Address:

City:

State:

Zip:

Submittal Date: Fri Jul 03 17:46:24 EDT 2015


528 of 2079 10/1/2015 11:02 AM




Informational Note: Federal Aviation Administration (FAA) Advisory Circulars (ACs) provide additional practices and methods for airportlighting.



DSC05118.JPGL-824 Cable installed in hand hole. Demonstrates the harsh environment that L-824 cable is designed to survive.

DSC05530.JPGL-824 Cable installed in manhole. Demonstrates the harsh environment that L-824 cable is designed to survive.

DSCN1369.JPGL-824 Cable installed exposed in airfield lighting vault (accessible to qualified persons only). Demonstrates the controlled environment of an airfield lighting vault.


L-824 cable is designed to withstand a very harsh environment of direct earth burial and installation underground in raceways, manholes, hand holes and light bases. Please see photos attached to this Public Comment.

It is an extremely rare occurrence for the L-824 cable to fail in the controlled environment of an airfield lighting vault. In my 28 years of airfield lighting experience, I am aware of only two cable failures. Both of these L-824 cable failures were caused by the breakdown of the equipment to which the L-824 cable was connected.

Airfield lighting series circuits are current circuits; where a short circuit is considered as no load. There is virtually no arc-flash hazard involved on the output of a constant current regulator.

The constant current regulator output current is designed to stay fixed at the FAA mandated values of 6.6 amps (±0.1 A) or 20 amps (±0.3 A). The constant current regulator (CCR) output overcurrent protective device will not trip due to a change in series circuit resistance, shorts, or grounds in the airfield lighting circuit. The CCR recognizes a change in series circuit resistance, shorts, or grounds in the airfield lighting circuit as a change in load characteristics, and it adjusts the output voltage up or down to maintain the specified current. An open circuit is understood as an infinite increase in load, causing the CCR to trip on overvoltage.

I respectfully request the CMP re-examine PI-2762 and approve the use of exposed runs of FAA type L-824 cables in (airfield lighting vaults) locations accessible to qualified persons only.

Related Item





Affilliation: none

Street Address:

City:

State:

Zip:

Submittal Date: Sat Jul 04 11:29:37 EDT 2015


529 of 2079 10/1/2015 11:02 AM




Informational Note: Federal Aviation Administration (FAA) Advisory Circulars (ACs) provide additional practices and methodsfor airport lighting.



DSCN1370.JPGPhoto demonstrates limited length of exposed L-824 cable at connection to constant current regulator. L-824 cable is equipped with L-823 connectors for quick change of CCR.

DSCN2203.JPGPhoto demonstrates limited length of exposed L-824 cable at connection to constant current regulator with Kellums wire basket cable grips for cable support. L-824 cable is equipped with L-823 connectors for quick change of CCR.


There are typically many thousands of feet of L-824 airfield lighting cable installed at airports; tens of thousands of feet at commercial airports. The requested exception is a very narrow application of the L-824 airfield lighting cable. The narrow limited application would be for use inside the airfield lighting vault. Access to the airfield lighting vault is limited to qualified persons. The free air cable length would typically be less than 5 or 6 feet and would nominally be supported by cable grips, ty-raps or other acceptable means.

I respectfully request the CMP re-examine PI-2762 and approve the use of exposed runs of FAA type L-824 cables in locations accessible to qualified persons only.

Related Item





Affilliation: none

Street Address:

City:

State:

Zip:

Submittal Date: Sat Jul 04 17:52:33 EDT 2015


530 of 2079 10/1/2015 11:02 AM


PI – 2762 - Revise Text

300.

37 37 Aboveground Wiring Methods.

Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in electrical metallic tubing,in RTRC and PVC conduit, in cable trays, in auxiliary gutters, as busways, as cablebus, in other identified raceways, or asexposed runs of metal-clad cable suitable for the use and purpose. In locations accessible to qualified persons only, exposedruns of Type MV cables, exposed runs of FAA L-824 cables , bare conductors, and bare busbars shall also be permitted.Busbars shall be permitted to be either copper or aluminum.

Informational Note: Federal Aviation Administration (FAA) Advisory Circulars (ACs) provide additional practices and methods forairport lighting.


Provide an alternative method that has proven successful over many years. It has been shown to be reliable, simpler and safe while providing more wiring options to maintaining the integrity of the series circuit..

Related Item

Public Input No. 2739-NFPA 70-2014 [New Section after 392.10(D)]


Submitter Full Name: Seward Ford

Organization: Visual Aids Services Inc

Affilliation: None

Street Address:

City:

State:

Zip:



531 of 2079 10/1/2015 11:02 AM


PI – 2762 - Revise Text

300.

37 37 Aboveground Wiring Methods.

Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in electrical metallic tubing,in RTRC and PVC conduit, in cable trays, in auxiliary gutters, as busways, as cablebus, in other identified raceways, or asexposed runs of metal-clad cable suitable for the use and purpose. In locations accessible to qualified persons only, exposedruns of Type MV cables, exposed runs of FAA L-824 cables , bare conductors, and bare busbars shall also be permitted.Busbars shall be permitted to be either copper or aluminum.

Informational Note: Federal Aviation Administration (FAA) Advisory Circulars (ACs) provide additional practices and methodsfor airport lighting. 300.37



DSCF2471.JPG

Typical Airport lighting vault utilizing raceways with FAA L824 cable which is accessible to those properly qualified as defined in FAA AC 150/5340-26C This practice has been in use for decades and facilitates troubleshooting and quick rewiring of constant current regulator circuits upon failure of regulator or wiring in the electrical vault.

DSCN0778.JPG

IMG_1397.JPGAlthough not shown in this picture it is common practice to run L824 cable in a raceway imbedded in the electrical vault floor covered by an appropriate grate which allow easy access to the cables should maintenance be required..


Allowing multiple L824 cables to be routed in raceways provides relatively quick access to cables in the electrical vault and with cables terminated with FAA L823 plugs and receptacles give the maintenance worker a number of options as to how to get a series circuit critical to the operation of a runway back in operation . Spare or alternate cable paths can quickly be patched in thus bypassing failed components or cable.

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Submitter Full Name: Seward Ford

Organization: Visual Aids Services Inc

Affilliation: None

Street Address:

City:

State:

Zip:



532 of 2079 10/1/2015 11:02 AM



Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in electrical metallic tubing, inRTRC and PVC conduit, in cable trays, in auxiliary gutters, as busways, as cablebus, in other identified raceways, or asexposed runs of metal-clad cable suitable for the use and purpose. In locations accessible to qualified persons only, exposedruns of Type MV cables, exposed runs of FAA L-824 cables, bare conductors, and bare busbars shall also be permitted.Busbars shall be permitted to be either copper or aluminum.

Informational Note: Federal Aviation Administration (FAA) Advisory Circulars (ACs) provide additional practices and methods forairport lighting.


Exposed runs of FAA L-824 cable is not specifically permitted in the NEC. Some authorities having jurisdiction do not see equivalence in permitting exposed runs of MV cables and exposed runs of L-824 cables in locations accessible only to qualified persons.

Substantiation:

Exposed portions of FAA L-824 Type C cable within airfield lighting vault buildings which have controlled access to qualified personnel only have been part of industry practice for decades. In particular, airfield lighting series circuits utilize series cutouts for maintenance and troubleshooting which may be wall mounted per the manufactures instructions. Wires connecting to the series cutout are exposed when the series cutouts are wall mounted. FAA L-824 Type C cable is permitted and rated by the manufacturers for aerial use in addition to underground direct burial, raceways, and in ducts. Aerial use is exposed above ground use. FAA advisory circular 150/5345-7E and F permits FAA L-824 Type C cable to be used in buildings and with controlled access by authorized personnel only the exposed cable complies with Article 300.37.

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Submitter Full Name: Matt Szabo

Organization: Aviation Alliance, Inc.

Affilliation: none

Street Address:

City:

State:

Zip:

Submittal Date: Wed Jul 15 13:00:30 EDT 2015


533 of 2079 10/1/2015 11:02 AM



Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in electrical metallic tubing, inRTRC and PVC conduit, in cable trays, in auxiliary gutters, as busways, as cablebus, in other identified raceways, or asexposed runs of metal-clad cable suitable for the use and purpose. In locations accessible to qualified persons only, exposedruns of Type MV cables, bare conductors, and bare busbars shall also be permitted. Busbars shall be permitted to be eithercopper or aluminum.


Public Input No. 2762-NFPA 70-2014 (Section No. 300.37)

• Comments to Substantiation commentary from Carl Johnson – Avcon10/29/14

Section No. 300.37 discusses the application and protection of L824 cables that are used to power airfield lights. The system is set up such that Edison Power, which is voltage controlled is brought into a vault on the airfield. The Edison power goes through switchgear to transform to airfield application needs and then is transformed via a plurality of constant current regulators to deliver power to airfield circuits that are current controlled in series. The constant current regulator is used to control current at specified steps or intensities to control the brightness of the lights on the airfield depending on varying visibility conditions. Each constant current regulator typically controls the lighting for a designated geographic area on the airfield (ie, Taxiway A Edge Lights, Runway 18 Centerline Lights, Runway 27 Edge Lights, Runway 9 Threshold Lights, etc.).

The airfield vault houses the switchgear and constant current regulator units and is similar to an electrical substation. It is the key area and acts as the brain of the airfield lighting system. Therefore, it is very important that the equipment is maintained and serviced to the highest quality standards to support the effective lighting of an airfield, which is critical to aircraft and personal safety.

It is a very controlled area. Only authorized personnel are allowed in the airfield vault for monitoring or maintenance needs. Carl Johnson II discusses some of those needs in his post from 10/29/14. The point I want to highlight is the criticality of timeliness of completion of those tasks. If there are issues that need to be diagnosed and tested on an airfield, the vault, regulators and their fed circuits must be accessed quickly and resolutions employed right away to prevent an unsafe airport operation.

Section No. 300.37 addresses the safety of access to L824 cables throughout the airfield environment which is open to many contractors and construction personnel as they work on electrical systems. The protection of these cables in conduit and the other protection devices mentioned is critically important to safety as the ability to control personnel that come into interaction with such cables is more difficult to manage. However, access to and in the vault is more controlled and procedures are validated and audited. Further, the equipment in the vault must be readily accessible to authorized personnel to properly maintain and control with timely solutions in an effort to protect the safety of everyone in an airfield environment that uses airfield lighting to transport passengers via aircraft.

It is critically important that authorized personnel have readily available access to L824 cables and those cables should be permitted to be installed in exposed runs in the airfield lighting vault only.

Related Item



Submitter Full Name: John Bogart

Organization: Integro

Affilliation: Integro - Airfield Lighting Manufacturer

Street Address:

City:

State:

Zip:

Submittal Date: Tue Aug 18 09:54:40 EDT 2015


534 of 2079 10/1/2015 11:02 AM

Public Comment No. 826-NFPA 70-2015 [ Section No. 590.4(G) ]

(G) Splices.

A box, conduit body, or other enclosure, with a cover installed, shall be required for all splices except where:

(1) The circuit conductors being spliced are all from nonmettalic multiconductor cord or cable assemblies, provided that theequipment grounding continuity is maintained with or without the box.

(2) The circuit conductors being spliced are all from metal sheathed cable assemblies terminated in listed fittings thatmechanically secure the cable sheath to maintain effective electrical continuity.


The proposed revision is to clarify that 590.4(G)(1) applies only to splices of cord/cable assemblies that have a "nonmetallic" jacket.

Clarity is needed.

Related Item

First Revision No. 616-NFPA 70-2015 [Section No. 590.4(G)]

Public Input No. 2847-NFPA 70-2014 [Section No. 590.4(G)]


Submitter Full Name: James Dollard

Organization: IBEW Local Union 98

Street Address:

City:

State:

Zip:



1168 of 2079 10/1/2015 11:02 AM

Public Comment No. 1143-NFPA 70-2015 [ Section No. 590.4(J) ]

(J) Support.

Cable assemblies and flexible cords and cables shall be supported in place at intervals that ensure that they will be protectedfrom physical damage. Support shall be in the form of staples, cable ties, straps, or similar type fittings installed so as not tocause damage. Cable assemblies and flexible cords and cables installed as branch circuits or feeders shall not be installed onthe floor or on the ground. Extension cords shall and multiconductor cord or cable of a type identified in Table 400.4 for hardusage or extra-hard usage shall not be required to comply with 590.4(J) . Vegetation shall not be used for support of overheadspans of branch circuits or feeders.

Exception: For holiday lighting in accordance with 590.3(B), where the conductors or cables are arranged with strain reliefdevices, tension take-up devices, or other approved means to avoid damage from the movement of the live vegetation, treesshall be permitted to be used for support of overhead spans of branch-circuit conductors or cables.


590.4(J) prohibits flexible cords and cables from being laid on the floor or ground for temporary installations. Adequate support is needed to minimize the possibility of damage to the wiring method during its temporary period of use, and support and physical protection is appropriate for temporary wiring methods such as NM cable that are not rated for the rough service of a construction or demolition site. However, hard usage and extra-hard usage cables are manufactured to remain intact while laid on the ground or floor and used in rough service, and where so marked, in wet locations. Some hard usage and extra-hard usage cables are extremely large and heavy and are impractical to hang from cable ties, straps, or similar fittings. Attempting to support large cables above grade could also create a greater hazard by forcing the use of stanchions to suspend heavy cables across large construction or demolition sites, or placing long runs of large, high-ampacity cable in plastic cable protectors (Yellow Jacket®) where heat retention may be damaging to the cable's insulation.This proposal was previously rejected (ref Public Input No. 1981-NFPA 70-2014) with Committee Statement of “Section 590.2(A) states “except as specifically modified in this article, all other requirements of this Code for permanent wiring shall apply to temporary wiring installations.” Since extension cords, multiconductor cords, and multiconductor cables that are hard usage or extra hard usage are already permitted for this application, inclusion in 590.4(J) for these cords and cables are not necessary. “A Technical Question was submitted to NFPA 9/15/2015, and Mark Cloutier NFPA Senior Electrical Engineer responded in part, “After discussions within our group the language in 590.2 is correct in that other requirements in the code apply unless amended by Article 590. However, the new language in 590.4(J) in the NEC 2014 clearly amends any permissive rules that in previous editions allowed the use of cords in the application you described and now prohibits flexible cords and cables installed as branch circuits and feeders from being installed on the floor or on the ground.” Mr. Cloutier’s response supports the position stated in Public Input No. 1981-NFPA 70-2014.I respectfully resubmit a proposal to modify the language of 590.4(J) to reinstate the use of hard usage and extra-hard usage cables on the floor or ground in temporary installations.

Related Item

Public Input No. 1981-NFPA 70-2014 [Section No. 590.4(J)]


Submitter Full Name: LORI WEIDNER

Organization: Kurion, Inc.

Affilliation: Hanford Electrical Codes Board

Street Address:

City:

State:

Zip:



1169 of 2079 10/1/2015 11:02 AM


(B) Use of Other Outlets.

For temporary wiring installations, receptacles, other than those covered by 590.6(A)(1) through (A)(3) used to supplytemporary power to equipment used by personnel during construction, remodeling, maintenance, repair, or demolition ofbuildings, structures, or equipment, or similar activities, shall have protection in accordance with (B)(1) or B(2). When usingB(1) or B(2) is not practical, the assured equipment grounding conductor program in accordance with (B)(2) 3), or (B)(4)should be allowed .

(1) GFCI Protection.

Ground-fault circuit-interrupter protection for personnel.

(2) SP GFCI Protection.

Special purpose ground-fault circuit-interrupter protection for personnel.

(3) Assured Equipment Grounding Conductor Program.

A written assured equipment grounding conductor program continuously enforced at the site by one or more designatedpersons to ensure that equipment grounding conductors for all cord sets, receptacles that are not a part of the permanent wiringof the building or structure, and equipment connected by cord and plug are installed and maintained in accordance with theapplicable requirements of 250.114, 250.138, 406.4(C), and 590.4(D).

(a) The following tests shall be performed on all cord sets, receptacles that are not part of the permanent wiring of thebuilding or structure, and cord-and-plug-connected equipment required to be connected to an equipment grounding conductor:

(2) All equipment grounding conductors shall be tested for continuity and shall be electrically continuous.

(3) Each receptacle and attachment plug shall be tested for correct attachment of the equipment grounding conductor. Theequipment grounding conductor shall be connected to its proper terminal.

(4) All required tests shall be performed as follows:

(5) Before first use on site

(6) When there is evidence of damage

(7) Before equipment is returned to service following any repairs

(8) At intervals not exceeding 3 months

(i) The tests required in item (2)(a) shall be recorded and made available to the authority having jurisdiction.

(4) EGFPD Protection.

Equipment ground-fault protective device.



EGFPD_vs_GFCIs.pdf Tripping time curves for Classes A, C and D GFCIs and EGFPDs


Substantiation for including SPGFCI devices in the standard:

Fatality Statistics continue to show electrocutions as a significant cause of death at the work place. The 2015 NFPA 70E Standard, Annex K states that electrocutions are the fourth leading cause of industrial fatalities. It also stated that the National Safety Council estimates that about 1000 fatalities every year are due to electrocution, where more that 50% of them take place on system voltage less than 600 V. Moreover, approximately 30,000 non-fatal electrical shock accidents occur every year.

UL 943C identifies protective devices designated as special purpose GFCI (SPGFCI) and thus designed to meet the both NEC and NFPA 70E definition of devices intended for personnel protection. Updating the NEC to include SPGFCIs designed and approved for industrial applications per UL 943C holds the promise of significantly reducing loss of life at the work place.

During the first draft meeting, CMP 2 recognized SPGFCIs as a potential improvement to safety and created FR-339 and FR-347 to include a new definition for SPGFCIs and an installation requirement in Article 210.8(B) respectively.


1170 of 2079 10/1/2015 11:02 AM

Tripping Characteristics

Source: UL 943

20 6

Class A

Classes C & D

EGFPD

Adjustable from 6 to 100 mA 20 6

References:

1. Underwriters Laboratories Inc. (UL), “Outline of Investigation for Special Purpose Ground-Fault Circuit-Interrupters”, UL 943C Edition 2, 2012.2. Online UL directory, “Guide Information for Special Purpose Ground-Fault Circuit-Interrupters”. [Online]: http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/showpage.html?name=KCYC.GuideInfo&ccnshorttitle=Special-purpose+Ground-fault+Circuit+Interrupters&objid=1074849623&cfgid=1073741824&version=versionless&parent_id=1074849622&sequence=1 3. IAEI Magazine, “Now that industrial GFCIs are here, inspectors have a proactive option for shock protection”, International Association of Electrical Inspectors (IAEI), pp. 30-35, Jan/Feb 2014. [Online]: http://www.iaei.org/blogpost/890108/178015/Now-that-industrial-GFCIs-are-here-inspectors-have-a-proactive-option-for-shock-protection 4. NFPA, "2015 NFPA 70E Standard." [Online]: http://www.nfpa.org/codes-and-standards/document-information-pages?mode=code&code=70e&tab=editions 5. Fire Protection Research Foundation report, "Occupational Injuries from Electrical Shock and Arc Flash Events", NFPA, March 2015. [Online]: http://www.nfpa.org/research/fire-protection-research-foundation/reports-and-proceedings/electrical-safety/other/occupational-injuries-from-electrical-shock-and-arc-flash-events

Substantiation for including EGFPD devices in the standard:

Although EGFPDs are rated as equipment protection by UL, they are tested to both UL943 GFCI standard and UL 1053 Ground-Fault Sensing and Relaying Equipment. Therefore, EGFPD offer protection similar to GFCIs. EGFPDs should not be confused with ground-fault protection of equipment (GFPE). EGFPDs are equipped with a tripping mechanism similar to GFCIs and therefore are capable of interrupting power when a ground-fault is detected.

EGFPDs use the same GFCIs tripping characteristic and therefore an EGFPD will clear a ground-fault within the same clearing time of a GFCI provided that the fault-current magnitude is higher than the device set trip level. EGFPDs differ from GFCIs in: 1. Tripping level is adjustable in the range of 6 to 100 mA (GFCIs have a fixed trip level; 6 mA for Class A and 20 mA for Classes C,D, and E) 2. Monitoring equipment grounding conductor continuity is not required (a mandate for Classes C, D, and E GFCIs).

Unfortunately, some industrial systems have natural leakage current of more than 20 mA during normal operation. The submitter of this PI has experiences a leakage of more than 50 mA while testing an arc welder and a plasma cutter. A similar situation was encountered at a brick manufacture running 6 wet saws (concrete cutters) feed from one source. For those systems, the use of Classes C, D, or E GFCIs defined by UL 943C is impractical. Therefore, EGFPDs could be used to provide some protection to personnel when GFCIs cannot be used.

Although, some commercial EGFPDs are equipped with internal means to monitor equipment grounding conductor continuity, this feature is not available in all devices because it is not a required feature by UL for these devices. Therefore, in order to insure the grounding conductor continuity, a ground continuity monitor relay can be used in conjunction with EGFPDs.

References: Online UL directory, “Guide Information for Equipment Ground-fault Protective Devices.” [Online]: http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/showpage.html?name=FTTE.GuideInfo&ccnshorttitle=Equipment+Ground-fault+Protective+Devices&objid=1074089034&cfgid=1073741824&version=versionless&parent_id=1073986917&sequence=1



Public Comment No. 618-NFPA 70-2015 [New Definition after Definition: Equipment.]

Related Item

First Revision No. 339-NFPA 70-2015 [New Definition after Definition: Ground-Fault Circuit Inter...]


Public Input No. 2196-NFPA 70-2014 [Section No. 590.6(B)(1)]

Public Input No. 2197-NFPA 70-2014 [New Section after 590.6(B)(2)]

Public Input No. 2191-NFPA 70-2014 [New Definition after Definition: Ground-Fault Protection of...]


Submitter Full Name: NEHAD EL-SHERIF

Organization: Littelfuse Startco

Street Address:

City:

State:

Zip:

Submittal Date: Sat Sep 12 14:10:07 EDT 2015


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Public Comment No. 691-NFPA 70-2015 [ Part IV. ]

Part IV. Listing Requirements

725.170 Listing and Marking of Equipment. The listed power source for circuits intended to provide power and data overClass 2 cables to remote equipment shall be as specified in 725.121(A)(1), (A)(2), (A)(3), or (A)(4). The power sources shallnot have the output connections paralleled or otherwise interconnected unless listed for such interconnection. Powereddevices connected to a circuit supplying data and power shall be listed. Nameplate ratings shall include rated voltage andcurrent available at the output of the listed power source equipment.


This Public Comment is one of a series on cable heating due to the transmission of power and data using cables that are typically bundled, and in support of the Public Comment to resolved Public Input 1837.

Presently there is no requirement for equipment listed to UL 60950 to have nameplate ratings. Without a nameplate rating, as required for Class 2 and Class 3 power sources, it is difficult to know or find the rated output voltage and current of a power source.

The Committee Statement is correct for Class 2 and Class 3 power sources. That is, the output wiring is not permitted to be paralleled, unless listed for the application, and the text preceding Tables 11(A) and (B) in Chapter 9 requires the “power source shall be durably marked where plainly visible to indicate the class of supply and its electrical rating.”

However, the above paragraph applies to Class 2 and Class 3 power sources. It does not apply to power sources listed in compliance with UL 60950. It is important for installation, inspection and evaluation of the system for change to have the nameplate ratings marked on the equipment.

While listed equipment may contain listed or “Recognized” power sources, the text of the requirement addresses the outputs of the listed equipment.






Related Item

Public Input No. 1838-NFPA 70-2014 [New Part after IV.]

Public Input No. 1837-NFPA 70-2014 [New Section after 725.154(C)]


Submitter Full Name: Terry Peters

Organization: SPI

Affilliation: SPI

Street Address:

City:

State:

Zip:



2065 of 2079 10/1/2015 11:02 AM


725.1 Scope.

This article covers remote-control, signaling, and power-limited circuits that are not an integral part of a device or , electricsign or of utilization equipment.

Informational Note: The circuits described herein are characterized by usage and electrical power limitations thatdifferentiate them from electric light and power circuits; therefore, alternative requirements to those of Chapters 1through 4, and Chapter 6 Article 600 are given with regard to minimum wire sizes, ampacity adjustment and correctionfactors, overcurrent protection, insulation requirements, and wiring methods and materials.


The sign industry has went to great lengths to formalize their wiring methods for Class 2 wiring and power sources in Article 600 to be specific to signs and outline lighting and not to further confuse sign requirements from other wiring systems.

Related Item



Submitter Full Name: Randall Wright

Organization: RKW Consulting

Affilliation: self

Street Address:

City:

State:

Zip:

Submittal Date: Tue Sep 22 16:33:08 EDT 2015


1803 of 2079 10/1/2015 11:02 AM

Public Comment No. 460-NFPA 70-2015 [ Section No. 725.3(C) ]

(C) Ducts, Plenums, and Other Air-Handling Spaces.

Class 1, Class 2, and Class 3 circuits installed in ducts, plenums, or other space used for environmental air shall comply with300.22.

Exception : As permitted in No. 1: Class 2 and Class 3 cables selected in accordance with Table 725.154 and installed inaccordance with 725.135(B) shall be permitted to be installed in ducts specifically fabricated for environmental air.

Exception No. 2: Class 2 and Class 3 cables selected in accordance with Table 725.154 and installed in accordance with725 .135(C) shall be permitted to be installed in other spaces used for environmental air (plenums).


The recommended text clarifies that 725.135 has explicit rules for ducts [725.135(B)] and other spaces use for environmental air (plenums) [(725.135(C)].

The current text does not comply with section 3.1.4.1 of the NEC Style Manual which requires that exceptions shall be written in complete sentences. Acceptance of the recommended text will result in compliance with the NEC Style manual.

Related Item

Public Input No. 1604-NFPA 70-2014 [Section No. 725.3(C)]




Affilliation: BICSI

Street Address:

City:

State:

Zip:



1804 of 2079 10/1/2015 11:02 AM

Public Comment No. 1397-NFPA 70-2015 [ Section No. 725.3(K) ]

(K) Installation of Conductors with Other Systems.

Installations shall comply with 300.8.

Installations for electric signs shall comply with 600.33


The clarify that Class 2 wiring for electric signs are controlled in Article 600 section 600.33 for their specific use. To again end the confusion with wiring between these articles.

Related Item






Submitter Full Name: Randall Wright

Organization: RKW Consulting

Affilliation: self

Street Address:

City:

State:

Zip:



1805 of 2079 10/1/2015 11:02 AM


725.24 Mechanical Execution of Work.

Class 1, Class 2, and Class 3 circuits shall be installed in a neat and workmanlike manner. Cables and conductors installedexposed on the surface of ceilings and sidewalls shall be supported by the building structure in such a manner that the cablewill not be damaged by normal building use. Such cables shall be supported by straps, staples, hangers, cable ties, or similarfittings designed and installed so as not to damage the cable. The installation shall also comply with 300.4(D). Metallic means

of support for flexible conduit and conductors shall be used in spaces above egress, which includes doorways, hallways, stairways,

corridors, passageways, lobbies, landings, and equivalent spaces.

Informa onal note: Nonmetallic supports exhibit significant weakening and failure during fires which can affect the safety of occupants

and emergency personnel entering and exi ng buildings due to entanglement in fallen cable.


Emergency responders and building occupant safety is at risk during building fires because people can become entangled and trapped in cabling which hasfallen out of molten or failing plastic supports/raceway. Even if people can free themselves from fallen cabling, this takes time which is otherwise needed toexit the building or fulfill the objectives of emergency personnel. The frequency of emergency responders becoming trapped in fallen cabling has become socommon that firefighters have created and publicly distributed training videos on how to escape in these situations(http://www.fireengineering.com/topics/m/video/36928837/the-quick-release-method.htm?q=cable+entanglement) [1].

There have been documented fatalities due to cable entrapment both in the U.S. and England. In Memphis, Tennessee, in 1994, a fireman was entangled incables that had fallen after the nonmetallic raceway collapsed due to the heat (http://www.fireengineering.com/articles/print/volume-148/issue-3/features/tragedy-in-a-residential-high-rise-memphis-tennessee.html [2]).More recently in England two firemen died due in part to being tangled in cabling that had fallen from plastic raceway in the ceiling of a Southampton residential building (http://www.bbc.co.uk/news/uk-england-hampshire-22126431 [3]). An article [4] in Electrical Contracting News identifies another recent incident in which a fireman died in Stevenage, Hertfordshire, after he became entangled in electrical cables which “had fallen after plastic trunking, the only support for the cables, melted and failed.” Article [4] goes on to report that changes are in process to Great Britain’s Wiring Regulations (BS 7671 [5]) to ensure that “wiring systems in any escape route should be supported so that they are not subject to premature failure in a fire.” Revisions have already been made in a standard for fire alarm system cabling, BS 5839-1 [6], to require cable supports/raceway which will not collapse in a fire.While the documented incidents involve firefighters, it is not even known how many building occupants may have died in the past either becoming entangled in fallen cabling, overcome by smoke/heat trying to remove a cabling obstruction, or forced to seek an alternate exit due to a significant amount of cablingobstruction.

NFPA 101 (Life Safety Code, 2012) [7] already addresses the requirement to maintain egress free from obstruction. Sections 7.1.10 and 7.1.10.1 (Means ofEgress Reliability) state,7.1.10.1 General. Means of egress shall be continuously maintained free of all obstructions or impediments to full instant use in case of fire or otheremergency.Sections 12.2.5.4, 12.2.5.4.2, and 12.2.5.4.3 (New Assembly Occupancies) and 13.2.5.4, 13.2.5.4.2, and 13.2.5.4.3 (Existing Assembly Occupancies) alsoemphasize this requirement.12.2.5.4 General Requirements for Access and Egress Routes Within Assembly Areas.12.2.5.4.2 Access and egress routes shall be maintained so that any individual is able to move without undue hindrance, on personal initiative and at any time,from an occupied position to the exits.12.2.5.4.3 Access and egress routes shall be maintained so that crowd management, security, and emergency medical personnel are able to reach anyindividual at any time, without undue hindrance.13.2.5.4 General Requirements for Access and Egress Routes Within Assembly Areas.13.2.5.4.2 Access and egress routes shall be maintained so that any individual is able to move without undue hindrance, on personal initiative and at any time,from an occupied position to the exits.13.2.5.4.3 Access and egress routes shall be maintained so that crowd management, security, and emergency medical personnel are able to reach anyindividual at any time, without undue hindrance

The solution that is easy to understand and enforce is a straightforward requirement regarding the allowable materials of a cable


1806 of 2079 10/1/2015 11:02 AM

support used above egress.Melting temperatures of metallic and non-metallic materials are significantly different – compare the low carbon steel melting temperature of approximately1450 °C versus 200-400 °C for many typical thermoplastics used in cable supports. This difference translates to a greater resistance to heat for steel whichenables a metallic support to survive and carry load significantly longer than nonmetallic supports. The intent is not to eliminate the use of non-metallicsupports/raceway in all applications, as they provide an appropriate and cost-effective option in other locations. The objective is to focus on egress whichcauses the highest risk to life safety.

In conclusion, there have been verifiable incidents in which firefighters have died due to entanglement from cabling fallen from plastic raceway that wasweakened due to fire. This is not just a theoretical discussion or anecdotal evidence. In addition, NFPA 101 already emphasizes the need to maintain egressfree from obstruction at all times, including during a fire. There is a clear opportunity in the NEC to improve consistency within NFPA Codes and save furtherloss of life.

Bibliography:[1] Fire Engineering Training Minutes. Presented by Mike Ciampo, Fire Department of New York. http://www.fireengineering.com/topics/m/video/36928837/the-quick-release-method.htm?q=cable+entanglement)[2] Chubb, M., and Joe Caldwell. 3/1/1995. “Tragedy in a Residential High-Rise, Memphis, Tennessee.” Fire Engineering,http://www.fireengineering.com/articles/print/volume-148/issue-3/features/tragedy-in-a-residential-high-rise-memphis-tennessee.html[3] April 15, 2013. “Shirley Towers flats blaze: ‘Possible safety breaches’”. BBC. http://www.bbc.co.uk/news/uk-england-hampshire-22126431[4] Rawlinson, J. August 2014, Vol. 34, No. 8, “Change for the Better.” Electrical Contracting News (ECN), pp. 24-25. http://edition.pagesuiteprofessional.co.uk/Launch.aspx?EID=dd8a7ebe-4f8b-4aa6-a9a1-d6b4692f6a23 (see attached)[5] BS 7671:2008+A2:2013, Requirements for electrical installations. IET Wiring Regulations. Seventeenth edition.[6] BS 5839-1:2013, Fire detection and fire alarm systems for buildings. Code of practice for design, installation, commissioning and maintenance of systemsin non-domestic premises[7] NFPA 101: Life Safety Code, 2012.





Related Item





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1807 of 2079 10/1/2015 11:02 AM


725.24 Mechanical Execution of Work.

Class 1, Class 2, and Class 3 circuits shall be installed in a neat and workmanlike manner. Cables and conductors installedexposed on the surface of ceilings and sidewalls shall be supported by the building structure in such a manner that the cablewill not be damaged by normal building use. Such cables shall be supported by straps, staples, hangers, cable ties, or similarfittings designed and installed so as not to damage the cable. The installation shall also comply with 300.4(D).

Informational Note: Paint, plaster, cleaners, abrasives, corrosive residues, or other contaminants may result in anundetermined alteration of Class 2, Class 3 and PLTC cable properties.


Mr. Tim West of Superior Cable submitted PIs dealing with painting or contaminating cables for the following mechanical execution of work sections, 725.24, 760.24, 770.24, 800.24, and 820.24.CMP 3 resolved PI 4717 with the statement that section 110.12(B) applies and an additional reference is not substantiated. Section 110.12 applies to equipment:110.12 Mechanical Execution of Work. Electrical equipment shall be installed in a neat and workmanlike manner.

The definition of equipment does not include cable.

Equipment. A general term, including fittings, devices, appliances, luminaires, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation.

We agree that painting or otherwise contaminating cables can change their properties, especially the fire protection properties of plenum cables. We prefer an informational note rather than mandatory text because the mandatory text recommended in the PIs is vague and unenforceable.

The informational note recommended by this Public Comment is based on the informational notes that were adopted by FR-4552 for 820.24 and FR-4592 for 830.24.






Related Item



Submitter Full Name: DAVID KIDDOO

Organization: CCCA

Affilliation: CCCA

Street Address:

City:

State:

Zip:

Submittal Date: Thu Jun 25 22:59:16 EDT 2015


1808 of 2079 10/1/2015 11:02 AM


(A) Power Source.

The power source for a Class 2 or a Class 3 circuit shall be as specified in 725.121(A)(1), (A)(2), (A)(3), (A)(4), or (A)(5):

Informational Note No. 1: Informational Note Figure 725.121, No. 1 illustrates the relationships between Class 2 orClass 3 power sources, their supply, and the Class 2 or Class 3 circuits.

Informational Note No. 2: Table 11(A) and Table 11(B) in Chapter 9 provide the requirements for listed Class 2 and Class3 power sources.

(1) A listed Class 2 or Class 3 transformer

(2) A listed Class 2 or Class 3 power supply

(3) Other listed equipment marked to identify the Class 2 or Class 3 power source

Exception No. 1 to (3): Thermocouples shall not require listing as a Class 2 power source.

Exception No. 2 to (3): Limited power circuits of listed equipment where these circuits have energy levels rated at orbelow the limits established in Chapter 9 , Table 11(A) and Table 11(B).

Informational Note: Examples of other listed equipment are as follows:

(4) A circuit card listed for use as a Class 2 or Class 3 power source where used as part of a listed assembly

(5) A current-limiting impedance, listed for the purpose, or part of a listed product, used in conjunction with anon–power-limited transformer or a stored energy source, for example, storage battery, to limit the outputcurrent

(6) A thermocouple

(7) Limited voltage/current or limited impedance secondary communications circuits of listed industrial controlequipment

(8) Listed audio/video information technology (computer) , communications, and industrial equipment limited-power circuits.

Informational Note: One way to determine applicable requirements for listing of information technology (computer)equipment is to refer to UL 60950-1-2011, Standard for Safety of Information Technology Equipment . Another wayto determine applicable requirements for listing of audio/video, information and communication technologyequipment is to refer to UL 62368-1-2014, Safety of audio/video, information and communication technologyequipment . Typically such circuits are used to interconnect data circuits for the purpose of exchanging informationdata. One way to determine applicable requirements for listing of industrial equipment is to refer to UL61010-2-201, Safety requirements for electrical equipment for measurement, control, and laboratory use –Part2-201: Particular requirements for control equipment , and/or UL 61800-5-1, Adjustable speed electrical powerdrive systems –Part 5-1: :Safety requirements –Electrical, thermal and energy.

(9) A dry cell battery shall be considered an inherently limited Class 2 power source, provided the voltage is 30 volts or lessand the capacity is equal to or less than that available from series connected No. 6 carbon zinc cells.


Including communications equipment as the source of a Class 2 circuit will cause confusion. The installation of communications equipment is covered in Chapter 8. Without a reference to this section from Chapter 8, the inclusion of communications equipment violates 90.3 which states:

"Chapter 8 covers communications systems and is not subject to the requirements of Chapters 1 through 7 except where the requirements are specifically referenced in Chapter 8."

The sole purpose of this Public Comment is to delete "communications". All the underlining was done by Terra View.

Related Item



Submitter Full Name: Stanley Kaufman

Organization: CableSafe, Inc./OFS


1810 of 2079 10/1/2015 11:02 AM


725.133 Installation of Conductors and Equipment in Cables, Compartments, Cable Trays, Enclosures, Manholes, OutletBoxes, Device Boxes, Raceways, and Cable Routing Assemblies for Class 2 and Class 3 Circuits.

Conductors and equipment for Class 2 and Class 3 circuits shall be installed in accordance with 725.135 through 725.143 144 .


This Public Comment is editorial to accommodate adding 725.144 in support of the Public Comment on Public Input 1837. Presently, 725.133 has installation requirements for Class 2/3 circuits. This proposed revision to 725.133 accommodates acceptance of 725.144, which was proposed by Public input 1837.




Public Comment No. 691-NFPA 70-2015 [Part IV.]


Related Item




Organization: SPI

Affilliation: SPI

Street Address:

City:

State:

Zip:



1812 of 2079 10/1/2015 11:02 AM


725.133 Installation of Conductors and Equipment in Cables, Compartments, Cable Trays, Enclosures, Manholes, OutletBoxes, Device Boxes, Raceways, and Cable Routing Assemblies for Class 2 and Class 3 Circuits.

Conductors and equipment for Class 2 and Class 3 circuits shall be installed in accordance with 725.135 through 725.143 144 .


This Public Comment is editorial to accommodate adding 725.144 in support of the Public Comment on Public Input 1837. Presently, 725.133 has installation requirements for Class 2/3 circuits. This proposed revision to 725.133 accommodates acceptance of 725.144, which was proposed by Public input 1837.






Related Item




Organization: SPI

Affilliation: SPI

Street Address:

City:

State:

Zip:



1812 of 2079 10/1/2015 11:02 AM


(A) Listing.

Class 2, Class 3, and PLTC cables installed in buildings shall be listed and labeled .



Essential_Guide_to_Product_Testing_and_Certification_NOV_2014.pdf

ETL Essential Guide to Product Testing & Certification 2014/2015 North American Edition. Please review document page numbers 5, 8 and 10 to see that ETL has requirements similar to UL, that products that do not bear their certification (listed) mark are not considered by ETL as being listed.


UL recognizes the Correlating Committee created a global First Correlating Revision (FCR) which directed that in all locations where the term “and labeled” was added after “listed” during the First Revision Stage, the words “and labeled” after “listed” be deleted, returning to previous text. UL understands that the Correlating Committee appointed a task group to address several issues involving the use of the terms “listed” and “labeled,” most importantly, to clarify and establish a distinction between the terms “listed” and “labeled” which are often used interchangeably. UL supports the need for this task group. However, UL does not expect the work of this task group to affect the 2017 NEC regarding the issue of “listed and labeled.” As such, UL is submitting comments to request that the words “and labeled” be added in various locations throughout the Code for the reasons expressed in the public inputs UL submitted on this issue. UL believes that these revisions will address an ongoing problem that should not wait until the 2020 NEC for resolution.

Subsequent to the Public Input Code Panel Meetings, UL has discussed this issue with its Electrical Council whose membership includes many AHJs. The proposed revisions to the NEC received general support from the membership. This issue was also discussed at a NEMA – NRTLs Forum held on August 14, 2015 at NEMA Headquarters. UL reiterated its support for the proposed revisions. The NRTLs represented at the meeting voiced no objection to the proposals.

The rationale for the revision was simple, to provide information to the AHJ regarding the suitability of equipment they encounter. The mark on the product is the manufacturer’s attestation that the product is in compliance with the appropriate standard. NRTL’s conduct factory surveillance of products, surveillance is one method to validate the manufacturer’s attestation. Should a product be found not to be compliant the manufacturer has the option of removing the mark and shipping the product without the mark, or holding the shipment and bringing the product into compliance. In either case the “Listing” is not impacted, as the “listing” is created at the completion of the “original” certification of the product and indicates the authorization but not the mandate to label products. So the only true way an AHJ can determine whether the product he is seeing is compliant with the applicable standard is via a label on the product. Taking it one step further, listings change with time. It is quite possible that a “listing” has been withdrawn; however labeled product may still be available for sale. Should equipment that is labeled, but not listed, be deemed acceptable? Based on the NEC definitions, it is possible to have a product that meets the Article 100 definition of listed but the testing organization made the manufacture remove the label for a non-compliance issue.

As for the concerns of products that are too small to be labeled, the definition of labeled is not limited to an actual label, it also includes symbols, or other identifying marks. The Safety Standards which define the listing requirements do not address labeling of products as defined by Article 100. As a general rule, NRTL’s do not consider a product as being listed unless it is also labeled. The UL White Book states that “Only those products bearing the appropriate UL Mark and the company's name, trade name, trademark or other authorized identification should be considered as being covered by UL's Certification, Listing, Classification and Follow-Up Service. The UL Mark provides evidence of listing or labeling, which may be required by installation codes or standards.” Again the requirements for the UL Mark are not a Safety Standard requirement, they are a UL requirement and the only way to show that a product is UL Certified (Listed); other NRTL’s have similar requirements.



Public Comment No. 532-NFPA 70-2015[Definition: Labeled.]

Provides information that a label may be permitted on a container in whichthe product is packaged.

Related Item



Public Input No. 1072-NFPA 70-2014 [Definition: Labeled.]



1813 of 2079 10/1/2015 11:02 AM

Submitter Full Name: JEFFREY FECTEAU

Organization: UNDERWRITERS LABORATORIES LLC

Affilliation: UL

Street Address:

City:

State:

Zip:



1814 of 2079 10/1/2015 11:02 AM

Public Comment No. 223-NFPA 70-2015 [ Section No. 725.135(K) ]

(K) Other Building Locations.

The following wires and cables shall be permitted to be installed in building locations other than the locations covered in725.135(B) through (I):

(1) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC cables

(2) A maximum of 3 m (10 ft) of exposed Type CL2X wires and cables in nonconcealed spaces


(4) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC cables installed in the following:

(5) Plenum communications raceways

(6) Plenum cable routing assemblies

(7) Riser communications raceways

(8) Riser cable routing assemblies

(9) General-purpose communications raceways

(10) General-purpose cable routing assemblies

(11) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, CL2X, CL3X, and PLTC cables installed in raceways recognized in Chapter 3

(12) Type CMUC undercarpet communications wires and cables installed under carpet, floor covering, modular tiles, or planks.Carpet, floor covering, modular tiles, or planks shall be free-floating and shall use interlocking means to attach to eachother or shall be adhered to the floor and shall be attached with release-type adhesives, but shall not be attached to thefloor using grout, nails, or screws. modular flooring and planks.


This is a two-part Public Comment.The first part is an editorial clarification. The submitter of PI 621 also submitted PI 2623 to change the name of Type CMUC from “Undercarpet communications wire and cable” to “Under-floor Covering communications wire and cable”. CMP-16 resolved PI 2623 with the statement:“There is no need to change the section title and table and alter the listing requirements in order to accommodate the use of these cables under modular flooring and planks.”

The wording of the Resolution statement for PI 2623 is clear that the intent is to permit installation “under modular flooring and planks” in addition to installation under carpet. Accordingly, this Public Comment recommends text that permits the installation of Type CMUC “under carpet, modular flooring and planks”. Companion Public Comments have been submitted to make the same editorial change in 800.113.

The second part is the deletion of the installation requirements. Class 2 and Class 3 circuits do not have any greater safety risk than a communications circuit. Therefore, it is hard to justify more stringent installation rules for communications under carpet wire and cable when used for Class 2 and Class 3 applications than when it is used for communications applications.

Note that this input has apparently been afflicted with the random underlining bug in the TerraWare software, and is not within the control of the submitter. This comment only deals with the installation of Type CMUC.



Public Comment No. 220-NFPA 70-2015 [Section No. 800.113(J)]

Public Comment No. 221-NFPA 70-2015 [Section No. 800.113(K)]

Public Comment No. 222-NFPA 70-2015 [Section No. 800.113(L)]


Public Comment No. 225-NFPA 70-2015 [Section No. 725.135(M)]

Related Item

First Revision No. 621-NFPA 70-2015 [Sections 725.135(K), 725.135(L), 725.135(M)]



1815 of 2079 10/1/2015 11:02 AM


Organization: CCCA

Affilliation: CCCA

Street Address:

City:

State:

Zip:



1816 of 2079 10/1/2015 11:02 AM

Public Comment No. 447-NFPA 70-2015 [ Sections 725.135(K), 725.135(L), 725.135(M) ]

Sections 725.135(K), 725.135(L), 725.135(M)

(K) Other Building Locations.

The following wires and cables shall be permitted to be installed in building locations other than the locations covered in725.135(B) through (I):

(1) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC cables



(4) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC cables installed in the following:







(11) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, CL2X, CL3X, and PLTC cables installed in raceways recognized in Chapter3

(12) Type CMUC undercarpet communications wires and cables installed under carpet, floor covering, modular tiles, or planks.Carpet, floor covering, modular tiles, or planks shall be free-floating and shall use interlocking means to attach to eachother or shall be adhered to the floor and shall be attached with release-type adhesives, but shall not be attached to thefloor using grout, nails, or screws.

(L) Multifamily Dwellings.

The following wires and cables shall be permitted to be installed in multifamily dwellings in locations other than the locationscovered in 725.135(B) through (I):

(1) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC wires and cables

(2) Type CL2X wires and cables less than 6 mm ( 1⁄4 in.) in diameter in nonconcealed spaces


(4) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC wires and cables installed in the following:







(11) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, CL2X, CL3X, and PLTC wires and cables installed in raceways recognized inChapter 3



1817 of 2079 10/1/2015 11:02 AM

(M) One- and Two-Family Dwellings.

The following wires and cables shall be permitted to be installed in one- and two-family dwellings in locations other than thelocations covered in 725.135(B) through (I):


(2) Type CL2X wires and cables less than 6 mm ( 1⁄4 in.) in diameter


(4) Communications wires and Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC cables installed in the following:










The second sentence should be deleted because the National Electrical Code is not an installation code for flooring. It is outside the scope of the NEC to have mandatory installation requirements (shall, shall not) for flooring.

Related Item





Affilliation: BICSI

Street Address:

City:

State:

Zip:

Submittal Date: Thu Aug 27 16:22:28 EDT 2015


1818 of 2079 10/1/2015 11:02 AM

Public Comment No. 224-NFPA 70-2015 [ Section No. 725.135(L) ]

(L) Multifamily Dwellings.

The following wires and cables shall be permitted to be installed in multifamily dwellings in locations other than the locationscovered in 725.135(B) through (I):




(4) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC wires and cables installed in the following:




















Public Comment No. 225-NFPA 70-2015 [Section No. 725.135(M)]

Related Item




1819 of 2079 10/1/2015 11:02 AM


Organization: CCCA

Affilliation: CCCA

Street Address:

City:

State:

Zip:



1820 of 2079 10/1/2015 11:02 AM

Public Comment No. 225-NFPA 70-2015 [ Section No. 725.135(M) ]

(M) One- and Two-Family Dwellings.

The following wires and cables shall be permitted to be installed in one- and two-family dwellings in locations other than thelocations covered in 725.135(B) through (I):




(4) Communications wires and Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and PLTC cables installed in the following:





















Related Item




1821 of 2079 10/1/2015 11:02 AM


Organization: CCCA

Affilliation: CCCA

Street Address:

City:

State:

Zip:



1822 of 2079 10/1/2015 11:02 AM


725.143 Support of Conductors.

Class 2 or Class 3 circuit conductors shall not be strapped, taped, or attached by any means to the exterior of any conduit orother raceway as a means of support. These conductors shall be permitted to be installed as permitted by 300.11(B)(2).725.144 Transmission of Power and Data.

The requirements of (A) and (B) shall apply to circuits that transmit power and data. The requirements in other Sections ofParts I and III shall apply, and 300.11 shall apply. The conductors that carry power shall be copper. The current in the powercircuit shall not be permitted to exceed the current limit of the connectors.

Informational Note No. 1: Section 725.144 provides unique requirements for cables that transmit power and data to apowered device.

Informational Note No. 2: One example of the use of cables meeting the requirements of (A) and (B) is transmittingpower and data to closed circuit TV Cameras (CCTV).

Informational Note No. 3: The RJ-45 connector is in widespread use with powered communications systems. Theseconnectors are typically rated for 1.3 amperes maximum.

(A) Types CL3P, CL2P, CL3R, CL2R, CL3, or CL2. Where Types CL3P, CL2P, CL3R, CL2R, CL3, or CL2 transmit power anddata, (1) through (2) shall apply, as applicable.

(1) The ampacity ratings in Table 725.144 shall apply at an ambient temperature of 30°C (86°F).

(2) For ambient temperatures above 30°C (86°F), the correction factors of 310.15(B)(2) shall apply.

Informational Note: One example of the use of Class 2 (Type CL2R) cables is a network of closed circuit TVcameras using 24 AWG, 60°C, Type CL2R, Category 5e LAN (local area network) cables.

(B) Types CL3P-LP(xxA), CL2P-LP(xxA), CL3R-LP(xxA), CL2R-LP(xxA), CL3-LP(xxA), or CL2-LP(xxA). TypesCL3P-LP(xxA), CL2P-LP(xxA), CL3R-LP(xxA), CL2R-LP(xxA), CL3-LP(xxA), or CL2-LP(xxA) shall be permitted to supplypower to equipment at a current level up to the marked ampere limit(xxA) and to transmit data to the equipment. Thecables shall comply with (1) through (3), as applicable.

Informational Note No. 1: The “(xxA)” in the text is the ampacity of each conductor in a cable based on the listingrequirements in 725.179.

Informational Note No. 2: One installation example of a limited power cable is a cable listed and marked TypeCL2-LP(0.5A), 23 AWG. Type CL2-LP(0.5), 23 AWG can be used in any location where a Type CL2 can be usedand the cable would be suitable for carrying up to 0.5 A per conductor regardless of bundle size. If used in a 7 cablegroup, Table 725.144 indicates that the same cable could carry up to 1.2 amperes per conductor, because it is 23AWG.

(1) Cables with the “-LP” suffix shall be permitted to installed in bundles, raceways, cable trays, communicationsraceways, or cable

routing assemblies.

(2) Cables with the suffix “-LP(xxA)” shall follow the substitution hierarchy of Table 725.154(A) and Figure 725.154(A) forthe cable

type without the “-LP(xxA) suffix.

(3) System design shall be permitted by qualified persons under engineering supervision.

TABLE 724.144 (SEE ATTACHMENT FOR TABLE 724.144)



Table_725.144.JPG Table 724.144


REFER TO UL FACT FINDING REPORT FOR DATA TO SUPPORT COMMENT

Related Item



Submitter Full Name: Roy Kusuma


1823 of 2079 10/1/2015 11:02 AM


725.143 Support of Conductors.

Class 2 or Class 3 circuit conductors shall not be strapped, taped, or attached by any means to the exterior of any conduit orother raceway as a means of support. These conductors shall be permitted to be installed as permitted by 300.11(B)(2).

RECOMMENDED TEXT AND SUBSTANTIATION FOR A NEW SECTION 725.144 ARE IN THE ATTACHMENT



SPI_Fact_Finding_Report_Issued_2015-09-25_UL_and_SPI.pdf UL FACT FINDING REPORT

Public_Comment_No._692-NFPA_70-2015_Section_No._725.143_9-25-2015.docx

Recommended text and substantiation for new section 725.144


RECOMMENDED TEXT AND SUBSTANTIATION FOR A NEW SECTION 725.144 ARE IN THE ATTACHMENT

See the attached UL Fact Finding Report on Power over Local Area Network Type Cables (4-Pair Data / Communications Cables) for supporting data.



Public Comment No. 688-NFPA 70-2015 [Section No. 725.179] Listing requirements for "Limited Power" -LP cables

Public Comment No. 689-NFPA 70-2015 [Section No. 725.133] Refers to new section 725.144

Public Comment No. 691-NFPA 70-2015 [Part IV.] Listing requirements for equipment

Related Item




Organization: SPI

Affilliation: SPI

Street Address:

City:

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Zip:



1825 of 2079 10/1/2015 11:02 AM

PUBLIC COMMENT ON PI 1837

PI 1837 proposed establishment of new 725.154(D). Renumber and revise PI 1837, as shown below.

*********************************************************************************************************************

725.144 Transmission of Power and Data. The requirements of (A) and (B) shall apply to circuits that transmit power and data. The requirements in other Sections of Parts I and

III shall apply, and 300.11 shall apply. The conductors that carry power shall be copper. The current in the power circuit shall not be

permitted to exceed the current limit of the connectors.

Informational Note No. 1: Section 725.144 provides unique requirements for cables that transmit power and data to a powered device. Informational Note No. 2: One example of the use of cables meeting the requirements of (A) and (B) is transmitting power and data to closed circuit TV Cameras (CCTV). Informational Note No. 3: The RJ-45 connector is in widespread use with powered communications systems. These connectors are typically rated for 1.3 amperes maximum. (A) Types CL3P, CL2P, CL3R, CL2R, CL3, or CL2. Where Types CL3P, CL2P, CL3R, CL2R, CL3, or CL2 transmit power and data, (1) through (2) shall apply, as applicable. (1) The ampacity ratings in Table 725.144 shall apply at an ambient temperature of 30°C (86°F).

(2) For ambient temperatures above 30°C (86°F), the correction factors of 310.15(B)(2) shall apply.

Informational Note: One example of the use of Class 2 (Type CL2R) cables is a network of closed circuit TV cameras using 24 AWG, 60°C, Type CL2R, Category 5e LAN (local area network) cables

(B) Types CL3P-LP(xxA), CL2P-LP(xxA), CL3R-LP(xxA), CL2R-LP(xxA), CL3-LP(xxA), or CL2-LP(xxA). Types CL3P-LP(xxA), CL2P-LP(xxA), CL3R-LP(xxA), CL2R-LP(xxA), CL3-LP(xxA), or CL2-LP(xxA) shall be permitted to supply power to equipment at a current level up to the marked ampere limit(xxA) and to transmit data to the equipment. The cables shall comply with (1) through (3), as applicable.

Informational Note No.1: The “(xxA)” in the text is the ampacity of each conductor in a cable based on the listing requirements in 725.179.

Informational Note No. 2: One installation example of a limited power cable is a cable listed and marked Type CL2-LP(0.5A), 23 AWG. Type CL2-LP(0.5), 23 AWG can be used in any location where a Type CL2 can be used and the cable would be suitable for carrying up to 0.5 A per conductor regardless of bundle size. If used in a 7 cable group, Table 725.144 indicates that the same cable could carry up to 1.2 amperes per conductor, because it is 23 AWG.

(1) Cables with the “-LP” suffix shall be permitted to installed in bundles, raceways, cable trays, communications raceways, or cable routing assemblies. (2) Cables with the suffix “-LP(xxA)” shall follow the substitution hierarchy of Table 725.154(A) and Figure 725.154(A) for the cable type without the “-LP(xxA) suffix. (3) System design shall be permitted by qualified persons under engineering supervision.

Table 725.144, Ampacities of Each Conductor (in Amperes) in a 4-Pair Class 2 or Class 3 Data Cables, Based on Copper Conductors at Ambient Temperature of 30°C (86° F) with all Conductors in All Cables

Carrying Current, 60°C (140°F), 75°C (167°F) and 90°C (194°F) Rated Cables AWG Number of 4-Pair Cables in a Bundle

1 2-7 8-19 20-37 38-61 62-91 92-192 Temperature Rating Temperature Rating Temperature Rating Temperature Rating Temperature Rating Temperature Rating Temperature Rating 60°C 75°C 90°C 60°C 75°C 90°C 60°C 75°C 90°C 60°C 75°C 90°C 60°C 75°C 90°C 60°C 75°C 90°C 60°C 75°C 90°C

26 1.0 1.0 1.0 1.0 1.0 1.0 0.7 0.8 1.0 0.5 0.6 0.7 0.4 0.5 0.6 0.4 0.5 0.6 NA NA NA

24 2.0 2.0 2.0 1.0 1.4 1.6 0.8 1.0 1.1 0.6 0.7 0.9 0.5 0.6 0.7 0.4 0.5 0.6 0.3 0.4 0.5

23 2.5 2.5 2.5 1.2 1.5 1.7 0.8 1.1 1.2 0.6 0.8 0.9 0.5 0.7 0.8 0.5 0.7 0.8 0.4 0.5 0.6

22 3.0 3.0 3.0 1.4 1.8 2.1 1.0 1.2 1.4 0.7 0.9 1.1 0.6 0.8 0.9 0.6 0.8 0.9 0.5 0.6 0.7

Note 1: For bundle sizes over 192 cables, or for conductor sizes smaller than 26 AWG, ampacities shall be permitted to be determined by qualified personnel under engineering supervision. Note 2: Where only half of the conductors in each cable are carrying current, the values in the table shall be permitted to be increased by a factor of 1.4.

Informational Note: The conductor sizes in data cables in wide-spread use are typically 22 – 26 AWG.

===========================

This substantiation is in three major parts:

Response to the request for information in “Resolved” Public Input 1837

Justification for the revised section number and text

Information regarding the editorially revised Table 725.144, based on a fact finding investigation.

The response to request for more information follows:

Panel 3 point #1: This public input does not meet the requirements of 4.3.4.1(d) of the Regulations Governing the Development of NFPA Standards. Technical substantiation was not provided in the Public Input for a new limited power cable as submitted in 725.154(D) and 725.179(L). This cable is allegedly being used for transmission of data and power using Table 11(A) and (B) in Chapter 9 for power, current, and voltage limitation with a new suffix of “LP” added to the cable. In Item No. 1 of this Public Input, the text requires the cable to be listed but failed to provide any of the listing requirements. Information on the new cable must be provided with all of the technical background data for the new cable. The cable, connection points in the system, enclosure requirements, marking requirements, if a conductor or a cable, sunlight resistant, wet location, dry location, evaluated for outdoor locations, plenum rated, limited combustibility, copper-clad, aluminum, solid, stranded, as well other technical data of the cable must be provided. Response to point #1: Much of Panel 3’s statement on point #1 seems to address Public Input 2366 for new 725.179(K), which

identified marking required on cable used for the transmission of power and data. The marking would be the result of a test lab’s’ test

criteria to assure cables would be suitable for the application requirements of 725.154. While Public Input 1837 suggested new text in

725.154, the text is fits well as installation requirements, so was renumbered to 725.144 for this Public Comment).

Panel 3 point #2: In Item No. 2 of this PI, the text states where installed in HVAC systems, the temperature rating of the conductors and cables shall be greater than the maximum permitted for that portion of the HVAC system. Further explanation of this concept is necessary since the text does not mention if the cables and conductors will be located inside of the listed HVAC equipment, external to the equipment, within the fabricated ducts and other spaces for environmental air (plenums), in outdoor locations, indoors, or both, humidity and other similar applications, as well as the maximum and minimum temperatures to which the cables and conductors will be exposed. Response to point #2: This Public Comment drops specific requirements related to NFPA 90A. The NFPA Standards Council with

decisions in the early 1980’s and early 2000’s made it clear that the Air Conditioning Committee has jurisdiction over combustibles in

HVAC systems. As general information for the panel, NFPA 101, Life Safety Code, 9.2.1 requires compliance with NFPA 90A and

NFPA 90A limits the maximum air temperature delivered within a duct or plenum to 121°C (250°F).

Panel 3 point #3: In Item No. 3, the text states that where cables extend beyond one building and are installed on rooftops the requirements of 310.15(B)(3)(a)(5)(c) and Table 310.15(B)(3)(c) shall apply. The first section in that reference appears to apply only to the adjustment factor of 60% for AC or MC Cable where these cables are stacked or bundled and would not apply to LP cable. The reference to application of 725.141 would only address cables or conductors subject to contact with electric light or power conductors over 300 volts to ground. This reference should be explained in detail for application and installation details.

Response to point #3: The requirements of 310.15(B)(3)(a)(5)(c) and Table 310.15(B)(3)(c) and the requirements of 725.141 already

apply, so there is no need to repeat them in this section.

Panel 3 point #4: In Item No. 4, “maintained spacing” is not explained and “not maintaining spacing” is not defined or explained for LP cables. Where these LP cables are not spaced properly (a spacing determination is not provided in the text), the temperature rating of the cables and the rating terminations cannot be exceeded without providing the technical documentation on the minimum and maximum rating of the cable or the terminations. Table 725.154(B) has been provided without any technical documentation of the origin of the Table, the conductor sizes, the ampacity provided, the value of the ampacity without maintaining spacing, what the spacing would be for the conductors or cables, as well as other pertinent data. This Table appears to apply to both LP cables and non LP cables based on Item No. 4 and Item No. 5.

Response to point #4: Panel 3 is correct: “Maintained-spacing” is not defined. However, for information, the term is used

“descriptively” in 392.80(A)(1)(c). Based on how Category cables are installed for data circuits, it is best to consider the cables as being

bunched, bundled, or stacked in a support system, such as cable tray or cable routing assembly. The table is the same as Table

522.22 in NEC-2014 and in the latest edition of NFPA 79, Table 12.5.1, except the two tables do not include 26 AWG conductors. A

table with ampacity rating for 24-30 AWG conductors first appeared in NFPA 79-1970. The substantiation for inclusion for either of

these tables was not found in the NFPA Technical Library, in spite of an extensive search by the librarian. Discussions with various

industry experts shed no light on the origin of the tables. It is suspected the origin may be the information in: Reference Data for

Engineers: Radio, Electronics, Computer, and Communications, Ninth Edition, Published 2001 (Wendy M. Middleton, Editor-in-

Chief)…last published edition.

It is important to identify the ampacity ratings of gauges smaller than 18 AWG, as Article 310 does have ampacity for conductors

smaller than 18 AWG.

Panel 3 point #5: In Item No. 5, the last sentence in this statement is the use of existing wiring shall be permitted only if the current supplied by the power source is sufficiently low to ensure that the temperature limitations of the conductors are not exceeded. There isn’t any explanation of what is meant by existing wiring, what it supplies, where the power source originates, what power supply level of current is sufficiently low enough to ensure the conductors will not overheat. Panel 3 has not received any technical data on an LP (limited power) cable, on Power over Ethernet, or any explanation of the pertinent issues involved with the Ethernet system

Response to point #5: There are many millions of feet of Category cable installed throughout the world in large and small buildings,

such as hospitals, banks, government, and educational facilities. The typical power source is the equipment listed in accordance with

UL 60950-1. The power, along with needed data, supplies many standard use items, Nurses Call, and CCTV cameras with or without

pan/tilt/zoom. The maximum current is calculated using the long-standing guidance found in Article 310 requirements, which

unfortunately, does not provide information on conductors smaller than 18 AWG. The information from the UL study on heat rise in

cables responds with requested information.

Panel 3 point #6: In addition, Panel 3 would entertain any other pertinent information that could be provided on this cable and Ethernet

application.

Response to point #6: The Panel 3 request for more information is difficult to present in a few words. The following paragraphs

provide basic information.

Background for why change is needed. Article 725 Class 2 and Class 3 circuits powered by 100 VA power sources have worked well

for decades. The circuit current is often in the milliampere range, with an increased current flow, as/if needed. Typically, conductor

gauge (as small as 26 AWGs) is sized (calculated) to assure sufficient voltage and current at the load. In 1973, this started to change:

Ethernet, which permitted the networking of computers, led to Dr. Metcalfe (and others) founding 3Com. The IEEE became interested;

resulting in a standard published in 2003: 803.2af-2003. This IEEE standard permitted transmission of data and a few watts of power

(15 w) over circuits that for years had been just data (sometimes coax). The initial use of a 4-pair cable for transmitting power and data

was power on 2 pairs and data on the other two pairs. In 2009 IEEE revised the standard (revised to 802.3at-2009) to permit more

power (30 w). Now IEEE is working on a standard (802.3bt) that will permit transmission of power and data over all 4 pairs in a

“Category” cable (est. 60 w). There are proprietary systems on the market that can deliver 200 watts, using 2 each 100 VA power

sources connected to a single 4 pair Category cable.

Presently, in addition to what is termed PoE, there is a fairly new type of system on the market, Power over HDBase T (PoH). PoH

(Association is HDBase T Alliance: hdbaset.org) seems to be focused on high performance video, such as providing data and power to

TV’s in homes or commercial establishments (e.g., sports bars). Conversely, PoE seems to be aimed at the commercial market: [e.g.,

CCTV cameras, nurses call systems and LED lighting. Both of these types of systems use Category cable. Another system that

provides power and data exchange is USB. USB 2.0 and 3.0 are in use all over the world, such as the cable to charge a cell phone or

connect peripheral equipment to a computer. USB 3.1 was recently presented at a major industry show: some specs tout a capability

of 20 volts and 5 amperes.

For years in commercial buildings (large or small businesses), the systems using Category cables supplied just data, so there was not a

heat rise issue for cables. With the introduction of power and data transmitted over conductors in a cable, the heat rise issue

addressed by Article 310 becomes relevant for Article 725. While Article 310 does not specifically address 22-26 AWG conductors, the

formulas are applicable.

A brief description of Category cable identification follows. The typical conductor size varies between 22 and 26 AWG. The

designation of the cable is in the format of U/UTP. A “U” means no shield or foil. Each of the 2 “U’s” can be either a “S” for shield or “F”

for foil. The letter before the “/” is the covering over all four pairs, but under the outer jacket. The letter after the “/” is the type of

covering on each or some of the four pairs. The “TP” stands for twisted pair. Sometimes there is no“/”, so the designation might be

UTP…meaning just twisted pairs.

The justification for the revised text follows:

Proposed Section 725.144 has installation requirements, which complement installation requirements that begin with 725.135. The

requirement to comply with 300.11 correlates with the requirements for Chapter 8 cables, which is applicable to bundles of cables.

There does not seem to be a reason to revise the application requirements that are covered in 725.154.

The text of 725.144 specifies that the requirements of (A) and (B) apply to circuits that combine transmission of power and data. This

means that the traditional Article 725 circuits that have had positive use for decades are not impacted.

The Informational Notes to 725.144, while not a requirement, provide guidance.

Section 725.144(A) provides installation requirements for cables without the “-LP” suffix. This could be an installation that was data

only, or systems in compliance with IEEE standards 802.3af and 802.3at. Testing at UL LLC shows that systems in compliance with

these 2 IEEE standards do not have a heat rise problem, due to the level of power delivered from the power source to the load.

Sections 725.144(A)(1)/(2) identify how to determine the ampacity capability of the conductors, and needed adjustments based on

ambient temperature. This section provides guidance for installation of new equipment and cables, where the cables do not have the “-

LP” suffix.

Section 725.144(B) provides installation requirements for cables with the “-LP” suffix, based on the listing requirements in Section

725.179. Section 725.144(B)(1) provides requirements for substitute cables: must have the -LP suffix and follow the guidance of

Table(A) and Figure 725.154(A). Section 725.144(B)(2) permits installation in all known methods. The marking on the cable with a “-

LP” suffix provides the current limitation for that cable to assure the cable temperature rating is not exceeded for any quantity of cable.

This section also permits design by qualified persons under engineering supervision.

Information regarding the editorially revised Table 725.144 follows:

One of the purposes of this Public Comment is to address these questions.

Question 1: Why is it necessary to adopt an ampacity table for Article 725 conductors when an ampacity table already exists in Article

310?

Answer: Article 725 cables often use conductor sizes 26, 24, 23 and 22 AWG. Article 310 has no specific data for conductor sizes smaller than 18 AWG. Power levels (and therefore current per conductor) have been increasing and continue to do so. For example, see http://www.silvertel.com/products/poe-power-over-ethernet.html for information about 200W equipment.

Question 2: Table 522.22, in Article 522, Control Systems for Permanent amusement Attractions, has ampacities for 26, 24 and 22

AWG conductors. Why isn’t this table applicable?

Answer 2: Table 522.22 has an ampacity value of zero for 26 AWG conductors at 60°C. Industry experience with millions of circuits

over many years [over a century…reference to plain old telephone circuits (POTS)] has demonstrated the safe use of 26 AWG cables.

The ampacity of 26 AWG conductors in Article 725 applications clearly is not zero. The origin/substantiation for ampacity values in

Table 522.22 is not available. A search by the staff at the NFPA library could not find the substantiation.

Question 3: How was the ampacity table in submitted in Public Input 1837 for Article 725 developed and why doesn’t it provide for

bundles of cable of various sizes?

The ampacity table in PI 1837 has been revised in this Public Comment based on extensive testing by UL LLC. See Fact-Finding Report UL Fact Finding Report on Power over Local Area Network Type Cables (4-Pair Data / Communications Cables) September, 2015.

http://www.silvertel.com/products/poe-power-over-ethernet.html

The recommended text clarifies that the installation rules for cables with and without the “-LP” suffix are the same. The installation rules

for cables with the “-LP” suffix do not mention compliance with the ampacity table because these cables are listed as having robust

enough characteristics to be safely installed. Having adequate current carrying capability is the key listing requirement for cables with

the “-LP” suffix.

The recommended text is clear that the use of cables with the “-LP” suffix is not required, but cables without the “-LP” suffix must

comply with the ampacity table. By permitting the use of cables without the “-LP” suffix, existing cables can be utilized for PoE type

applications, especially in the older low-power systems.

Further, Informational Note No. 2 following 725.144(B) provides an example of a Class 2 cable, rated for a maximum 0.5 ampere. The

cable is marked Type CL 2-LP(0.5A), 23AWG. It explains that the cable is permitted be installed anywhere a Type CL 2 cable is

permitted to be installed and that it would not exceed its 60°C temperature rating when installed in free air or enclosed and the current

on each conductor is up to 0.5 ampere. The informational note also explains that this 60°C Type CL 2-LP(.5A), 23AWG cable could be

installed anywhere a Type CL 2 23 AWG cable could be installed, including in a 7-cable bundle where it is permitted to carry up to 1.2

ampere per conductor.

The ampacity table, Table 725.154 in the Public Input 1837, is renumbered to Table 725.144 in the recommended text. The revised

ampacity table utilizes data from UL LLC to provide ampacities for 60°C (140°F), 75°C (167°F) and 90°C (194°F) rated cables in the

large and small bundles of cables encountered in real installations. It also utilizes, wherever possible, existing ampacity data in the

NEC.

The ampacities in Table 725.144 for 22 and 24 AWG cables are taken from Table 522.22. The ampacity of 23 AWG cable is derived

from the ampacity of 24 AWG cable by multiplying by the ratio of ratio of the cross-sectional area for 23 and 24 AWG conductors,

509/404=1.26; 2 x 1.26 = 2.52.

Table 522.22 has an ampacity value of zero for 26 AWG conductors at 60°C. Industry experience with millions of circuits over many

years (a century) has demonstrated the safe use of 26 AWG cables. The ampacity of 26 AWG conductors in communications

applications clearly is not zero. The origin/substantiation for ampacity values in Table 522.22 is not available. A search by the staff at

the NFPA library could not find the substantiation. The recommended text has a value of 1.0 ampere for the ampacity of a 26 AWG

conductor in an installation of 1 cable. That value equals the ampacity of 26 AWG conductors in the 75°C column is Table 522.22 and is

slightly less that the 1.3 ampere ampacity of a 26 AWG “wiring confined” conductor Reference Data for Engineers: Radio, Electronics,

computer, and Communications, Seventh Edition.

All the other ampacity values in Table 725.144 are based on data from UL LLC and are shown below.

Table 840.160(A), ampacity data, before rounding to one significant figure.

30°C Temperature Rise (60°C Cable Rating @30°C Ambient)

Conductor Size (AWG)

Number of 4-Pair Cables in a Bundle

1 2-7 8 -19 20 - 37 38 - 61 62-91 92 - 192

26 1.98 1.001 0.707 0.549 0.460 0.449 NA

24 2.209 1.187 0.813 0.634 0.546 0.455 0.398 23 1.242 0.893 0.674 0.582 0.590 0.452

22 1.499 1.04 0.765 0.663 0.68 0.527




1 2-7 8 -19 20 - 37 38 - 61 62-91 92 - 192

26 2.424 1.227 0.874 0.677 0.572 0.554 NA 24 2.732 1.461 1.009 0.782 0.674 0.561 0.478

23 1.531 1.105 0.834 0.718 0.718 0.549

22 3 1.857 1.284 0.952 0.822 0.826 0.631




1 2-7 8 -19 20 - 37 38 - 61 62-91 92 - 192

26 2.796 1.417 1.015 0.784 0.665 0.642 NA

24 3.172 1.692 1.174 0.907 0.781 0.651 0.549 23 1.775 1.284 0.968 0.831 0.823 0.628

22 2.158 1.489 1.11 0.955 0.947 0.717

In some powering schemes, two pairs in a 4-pair LAN cable are used for powering and two pairs are used for data. In that case, the UL

LLC report indicates that a factor of approximately 1.4 would be valid to estimate how much additional current could be carried by a 4-

pair cable when only ½ of the conductors are powered. Note 2 in the recommended text for Table 725.144 permits an adjustment

(increase) of the ampacity if only two the pairs in the 4-pair cable are used for powering.

The Table 725.144 column headings (2-7, 8-19, 20-37, 38-61, 62-91 and 92-192) were chosen because the UL LLC study used concentric bundles of 7, 19, 37, 61 and 91 cables; see illustration below. The 192 cable bundle size was chosen based on a typical telecommunications equipment rack containing four 48-port patch panels.

The Cambridge dictionary defines the term ‘bundle’ as “A number of things that have been fastened or are held together". The use of the term bundle in the recommended text is consistent with definition in the Cambridge dictionary. The UL LLC study generated temperature rise versus current curves for each confirgration tested. The data for temperatue rises of 30°C, 45°C and 60°C were used to develop Table 725.144 with a standard ambient temperature of 30°C. The same data can be used to generate ampacities for a 45°C ambient.

Installation of cables with the “-LP” suffix may future-proof the installation. Section 90.1(B) Adequacy, states:

(A) Adequacy. This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.

The informational note following Section 90.1states:

Informational Note: Hazards often occur because of overloading of wiring systems by methods or usage not in conformity with this Code. This occurs because initial wiring did not provide for increases in the use of electricity. An initial adequate installation and reasonable provisions for system changes provide for future increases in the use of electricity.

The recommended revisions in this Public Comment provide for installations that use cables without the “-LP” suffix. These installations will be “essentially free from hazard” but are “not necessarily efficient, convenient, or adequate for good service or future expansion”. The recommended revisions in this Public Comment provide for installations of cables with the “-LP” suffix. These installations are intended to provide an “initial adequate installation and reasonable provisions for system changes”. Future technology changes may further require NEC changes.

Copyright © 2015 UL LLC Copyright © 2015 SPI: the plastics industry trade association Page 1 of 168

Fact Finding Report

on

Power over Local Area Network Type Cables (4-Pair Data / Communications Cables)

SPI: the plastics industry trade association Washington, DC

Fact-Finding Investigations are undertaken to develop facts and issue a Report for use by the Applicant in seeking amendments in nationally recognized installation codes and standards. The issuance of this Report does not constitute an endorsement of any proposed amendment and in no way implies Listing, Classification or other recognition by UL and does not authorize the use of UL Listing or Classification Marks or any other reference to Underwriters Laboratories Inc. on, or in connection with, the product.

UL LLC, its employees, and its agents shall not be responsible to anyone for the use or nonuse of the information contained in this Report, and shall not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use of, or inability to use, the information contained in this Report.

UL LLC authorizes the above named company to reproduce this Report provided it is reproduced in its entirety.


ContentsINTRODUCTION ............................................................................................................. 3

GENERAL ................................................................................................................... 3

OBJECTIVES .............................................................................................................. 4

DISCUSSION .............................................................................................................. 4

PLAN OF INVESTIGATION ............................................................................................ 7

General ........................................................................................................................ 7

Samples ....................................................................................................................... 7

General Test Conditions .............................................................................................. 8

TEST EQUIPMENT AND SET-UP ................................................................................ 12

TEST DATA .................................................................................................................. 15

Thermal Response to Current ................................................................................... 15

Specific Conductor Ampacities for Cables in a Bundle .............................................. 18

Configurations where only ½ of the Conductors are Powered ................................... 27

Effects of Current ....................................................................................................... 31

Different Installation Methods .................................................................................... 32

Enclosing Cables ....................................................................................................... 34

Installation Orientation ............................................................................................... 36

Firestop ...................................................................................................................... 38

Cable Comparisons ................................................................................................... 42

Cable Configurations ................................................................................................. 44

LP Cables .................................................................................................................. 45

LP CABLE REQUIREMENTS .................................................................................... 46

SUMMARY .................................................................................................................... 47

APPENDIX A - CABLE DETAILS .................................................................................. 48

APPENDIX B - TEMPERATURE TEST DATA .............................................................. 96

APPENDIX C - DATA for NEC TABLES ..................................................................... 150

APPENDIX D - CABLE HEATING TEST ..................................................................... 167


INTRODUCTION

GENERAL

The following is a report on the heating effects of dc current on 4-pair local area network (LAN) cabling when configured in various bundle sizes and simulated installation conditions. Typically these cables are 4-pair “Category” type cables originally designed and intended for the transmission of data and communications. However, changes in technologies and equipment design have resulted in these cables increasingly being used to provide low voltage (<60 Vdc), limited power along with the data and communications signals. Power levels have been steadily increasing and are expected to continue to do so. In addition, these cables are often installed in bundles where cumulative heating effect of the numerous cables in the bundle combined with limited heat dissipation for the cables buried inside of the bundle raise concerns about exceeding the temperature ratings of the cable. The current (2014) version of the National Electrical Code (NEC), NFPA 70, covers data and communications circuits in Articles 725 and Chapter 8 respectively. Article 725 references Table 11(B), Class 2 and Class 3 Direct-Current Power Source Limitations, for power and current limitations on these circuits. Chapter 8 contains no specific requirements or references on power or current limitations on these circuits. Existing data from a number of sources has suggested that the present current limits in the NEC, where they exist, are too high for these cabling systems and the way they are deployed.

As part of the revision cycle for the 2017 National Electrical Code (NEC), public inputs were received related to remote powering over local area networking cable. The public inputs suggested that the existing Class 2 limits in Table 11B of the NEC permitted maximum currents that could result in the overheating of cables and recommended adding ampacity limitations for these applications based on wire size (AWG) and bundle size. In addition, the public inputs suggested that special cable designs could be developed and that might be used as alternatives to more traditional cables and AWG size alone with less restrictions on cable designs and the installations.

These public inputs resulted in proposed first revisions for the NEC that include requirements for limiting the power and conductor ampacities of powering over communications cable systems based on wire gauges and bundle sizes. In addition, a provision was included for special cables (“LP” cables) that could be used as


alternatives to more traditional cables that would allow for innovative cable designs and less restrictions on the installations.

At the time of the development of the proposed first revisions, there was very little hard data to support the inclusion of comprehensive ampacity tables. As a result, the proposed ampacity table only included single cables and multi-cable bundles. In addition, although “LP” cables were included as alternatives to traditional cables, there were no listing requirements for “LP” cables or listed “LP” cables. To support the development of more comprehensive ampacity tables and the development of listing criteria for “LP” cables, the industry commissioned UL to conduct a fact-finding investigation to develop data to support these objectives.

OBJECTIVES

1) Develop data to support changes to the National Electrical Code (NEC), NFPA70, (Articles 840 and 725)

2) Development of requirements for the listing of LP cable 3) Determine what parameters affect a cable’s ability to handle current in a bundle.

a. What effect does Wire Gauge Have on Cable Heating Cable Heating? b. What effect does Cable Construction Have on Cable Heating? c. What effects do Cable Construction Materials Have on Cable Heating?

4) Determine the effects of different installations (i.e. bundle size, routing, enclosing) on cable heating.

a. What effect does the installation have on cable heating b. Assess the worst case installation scenarios and what conditions have the

most heat rise. 5) Investigate the combined effects of higher levels of power applied over

communications cables under typical installation practices permitted by the NEC

DISCUSSION

Powering over LAN Cable systems provide both data and power in one cable, usually connected through an RJ45 style 8-pin connector. It encompasses any one of a number of standardized and proprietary systems that provide data and power to low power demand devices such as IP telephones, wireless access points, or IP cameras.

Low power systems are usually configured in a 2-pair powering configuration while “higher” power systems (still power limited) may require a 4-pair powering scheme.



On systems where data utilizes only 2-pairs, a 2-pair powering scheme may be carried on the unused cable pairs or on the same conductors as the data.

2-pair (4-wire) Powering Configurations:

On higher data capacity systems, where all 4 pairs are needed for data transmission speed, power is carried on the same -pairs as the data in either a 2-pair or 4-pair powering scheme.

2-Pair (4-wire) and 4-Pair (8-wire) Powering Configurations

As can be seen from these circuit diagrams, the present state of implementation is to utilize two pairs of conductors for each power circuit. This true whether the system applies the power to the unused conductors of a cable or applies a common-mode voltage to the data pairs. This means that for a given circuit, the current in the circuit is carried by two conductors and therefore the current for the circuit is halved for each individual conductor.


PLAN OF INVESTIGATION

General

Several possible investigation plans were considered. The first involved selecting a number of installation configurations considered to be representative of both typical installations and worst-case heating. This would be based on data already circulating on this subject. Different cable types would be tested in the various configurations. The second approach would concentrate on installation configurations, testing a wider variety of configurations using a single cable type. The results of these tests could then be used to determine a much narrower set of useful test configurations that could be used to test other cable types. Since this second approach would yield hard data that not only better supports the final test configurations but would also provide valuable data to support the NEC proposals related to powering over LAN cable, this is the approach that was chosen.

Samples

There were six distinct types of LAN cables tested as part of this investigation. Sample No. Description

1 CAT 5E 24AWG UTP (YELLOW)

2 CAT 5E 26AWG STRANDED FTP SHIELDED PATCH (LT Grey)

3 CAT 6 23AWG UTP RISER CMR (Blue)

4 CAT 6 23AWG UTP PLENUM CMP (White, Pink)

5 CAT 6 22AWG UTP PLENUM CMP (Blue)

6 CAT 6A 23AWG SHIELDED PLENUM (Dark Grey)

These cables were selected to:

Include the lightest and heaviest wire gauges


Include different diameters which will affect the thermal characteristics Refer to Appendix A for detailed cable descriptions.

General Test Conditions

Thermocouples

Thermocouples would be placed on the cable jacket at various positions along the cable bundle length and at various depths in the tray or bundle. For example (from CENELEC TR 50174-99-1):

In addition, a TC would be placed on an individual insulated conductor inside of the center cable. This arrangement shall provide us with the following:

Hard data showing where the greatest heating takes place A thermal profile along the length of the cable showing where the “end effect”

becomes a concern (i.e. how close to the end shall the added radiating surface area significantly affect the results?).

Data showing if the individual wire insulation is subjected to higher temperatures than the overall cable jacket.

Current

The present implementations of powering over LAN cable utilize two 2-pair wires for each powering circuit.


As a result, test conditions are often reported as having some amperes per pair. However, in the power world, power is often considered to be delivered over a single “pair” of wires; the “+” conductor and the “-” conductor.

This has led to some confusion of whether the specified current for a test is on two pairs of conductors with each conductor carrying ½ the current or on a single pair of conductors with each conductor carrying the specified current. The NEC proposals deal with power per circuit and amperes per conductor. Amperage designations would utilize amperes per conductor to avoid any confusion. This can easily be converted to any implementation later as needed. Since the original PoE specification used 175 mA/conductor, testing would be conducted starting at this current just as a benchmark. The next implementation of PoE is expected to be in the range of 60 watts which translates to 0.3 amperes per conductor so this would be another desirable data point. After that steps of 0.5 amperes per conductor and 1.0 amperes per conductor were discussed. To accommodate future technologies, the NEC is proposing Class 2 limits that would permit up to 1.6 amperes per conductor at 60 volts. However, since the NEC Class 2 current limits are based on a power limit of 100 watts and the current limits are defined as 100/V for voltages between 20-60 Vdc, the maximum permissible current changes based on the circuit voltage. Although it is expected that higher voltages would be more desirable from a loss standpoint, there could be reasons why lower voltages might be considered. For example, there is a lot of available equipment and components available for 48Vdc because of its usage in telecommunications. With these systems, the minimum operating voltage would be 40V. As a result of the above, the plan was to test each configuration over a range of 0.5 amperes to 2.5 amperes at .25 ampere increments with the addition of the original 175 mA as a reference point that might be useful for comparing results with testing already performed by others. The same test sample would be used and the current increased


after temperature stabilization without shutting the test down. This is to avoid going back down to ambient temperature for every amperage setting tested, per this example.

TestConfigurations

Bundle sizes were selected based on the hexagonal densest packing structure. This has been shown to yield the hottest temperatures due to cable density and the fact that with this structure each new layer completely encloses the previous layer trapping heat. This structure is characterized by the following number of cables in a bundle:

Where:

N is the total number of cables in the hexagonally densest packing structure;

n is the number of layers, surrounding the center cable. This results in N= 1, 7, 19, 37, 61, 91, 127, ....

At the high end, a bundle size of 192 was selected. This was based on 8 bundles of 24 cables that is typical of cabling coming off a server frame and considered a reasonable worse-case bundle size.

In addition to open bundles, additional configurations were considered: Bundles in conduit with and without fire stop Cables in an open wire mesh rack Cables in a closed cable tray with and without fire stop Closed Cable tray with fire stop.

The Category 5e, 24 AWG would be used for the installation configuration testing after which the other types of cables would be tested.



TEST EQUIPMENT AND SET-UP

TestFixtures

Test fixtures used to mount the cable bundles were constructed out of 2” schedule 40 PVC pipe.

Parachute cord was used to support the cable bundles to minimize any heat-sinking effects.

DataAcquisition

Temperature and current were measured using Agilent data acquisition / switch units amd a laptop PC with suitable data acquisition software. This photo shows the typical test set-up with a laptop, Agilent data acquisition unit, precision shunt resistor and power supply. The handheld meter is just used for continuity checks.


Agilent Model # 34972A LXI Data Acquisition / Switch Unit

Agilent Model # 34970A Data Acquisition / Switch Unit

Powersources

Constant Current power supplies: VOLTEQ Model # HY30005EX Maximum DC voltage of 300V and 5A, and maximum DC power of 1500W

BK Precision Model # 1685 B 1-60V, 5A Switching DC Power Supply

MeasuringCurrent

Current measurements were made via measuring the voltage across a calibrated precision shunt resistor with the Agilent data acquisition units.


WiringDiagramExamples

For larger bundles where the total dc resistance of the cables exceeded the power source’s ability to drive the necessary current, multiple power sources were used. The cables in the bundle were electrically divided such that the dc resistance of each set of layers would not exceed the power source’s ability to deliver the necessary current through the conductors.


TEST DATA

Thermal Response to Current

The data shows that as the current per conductor increases, the measured temperature on the cable increases. This is an example of the measured temperature data.

Refer to Appendix B for the complete set of temperature data.

Here is some information on how to interpret the data.


The data shows that increases in the number of cables in a bundle resulted in increases in measured temperatures. This chart shows and example of how the temperatures increase with increasing bundle size for a Cat 5e, 24 AWG cable.



Specific Conductor Ampacities for Cables in a Bundle

The data shows that overheating does not occur at 175 mA per conductor (35 watts) regardless of the cable type, bundle size or installation method. This represents existing implementations of powering, such as PoE and PoE+. This is clearly shown in the accompanying chart that shows the temperature rise for a wide variety of scenarios tested at 175mA. Overheating does not occur even if the data is corrected for a 30oC ambient or a 45oC ambient.

The also data shows that overheating does not generally occur at 0.3 amperes per conductor (60 watts) which represents some of the newer higher power systems. This is clearly shown in the accompanying chart that shows the temperature rise for a wide variety of scenarios tested at 0.3 amperes per conductor. Overheating does not occur even if the data is corrected for a 30oC ambient or a 45oC ambient.

Even under extreme installation conditions using 576 cables very tightly packed into an open wire cable tray it can be calculated that a 30 degrees C rise would not occur until the current reached 0.303 amperes.

y = 321.64x2 + 3.1692x - 0.4149; For y = 30 (oC), x = 0.303 Amperes




However, once the power goes up to the 100 watt powering range, or about 0.5 amperes per conductor, the data shows that under many installation conditions, overheating occurs. Only a combination of smaller bundle sizes, larger wire gauges and specialty constructions do not overheat when ambient conditions of 30oC or 45oC are considered. This is shown in the accompanying chart that shows the temperature rise for a wide variety of scenarios tested at 0.5 amperes per conductor. Overheating occurs even if the data is not corrected for a 30oC ambient or a 45oC ambient.

There are systems available and more under consideration that are providing 4-pair powering of up to 200 watts or about 1 ampere per conductor. The data shows that for a significant number of installation conditions and cable types cables will overheat at 1 ampere per conductor. This is shown in the accompanying chart that shows the temperature rise for a wide variety of scenarios tested at 1 ampere per conductor. Overheating occurs even if the data is not corrected for a 30oC ambient or a 45oC ambient.




Copyright © 2015 UL LLC

Copyright © 2015 SPI: the plastics industry trade association Page 25 of 168

In order to gather data for the development of a more detailed ampacity table for the proposed Table 840.160(C) in the NEC first revision, testing was conducted using cables with various AWG wire sizes configured in different size bundles. Bundle sizes were selected based on the hexagonal densest packing structure previously described. The bundles were enclosed in conduit representing a worst-case installation condition.

Temperatures were recorded at various current levels. In all but a few cases1 at least 4 data points were recorded for each wire gauge and bundle size and used to establish best-fit polynomial trendline curves such as these examples.

The curves permit the identification of the current that would yield a particular temperature. A complete set of these data graphs is provided in Appendix C.

For accuracy, rather than visually use the graphs to determine the current value, the formula for the best-fit polynomial trendline is used with an iterative methodology to solve for “x” at a temperature “y” of 30oC, 45oC and 60oC, representing 60, 75 and 90oC cables. An example of the resulting table is shown below.

In this example, the “Best-fit Formula (Enclosed)”row contains the actual “y” values generated by the formula for the curves using the “Amperes” as the “x” value. The objective is to get as close as reasonably possible to the target temperatures. For the 19 cable bundle the best fit formula is y = 39.857x2 + 4.1207x + 0.3159. By adjusting the

1 In a few cases then cable failed (insulation melted) before accurate stabilized data could be obtained for a particular AWG/bundle configuration. These are noted in the graphs associated with these cases.



current “x” to 0.813 amperes, we get very close to the target temperature of 30oC (30.0103) indicating that based on the data and the resulting curve, a current of 0.813 amperes would result in a temperature rise of 30oC for the cable.

The notation “R2” on the plots is a statistical measure of how close the data are to the fitted trendline. When you have a scatterplot of data, and try to fit a line/curve to the data, the "measure of goodness" for the fit is reflected in the R2 value. An R2 value of 1 is a perfect fit.

All of the data, trendline curves, formulas and tables can be found in Appendix C.

The following is a summary of the data, arranged in a style that could be used to populate more comprehensive tables for the NEC.


Conductor Size

(AWG)


1 2-7 8 -19 20 - 37 38 - 61 62-91 92 - 192

26 1.98 1.001 0.707 0.549 0.460 0.449 NA 24 2.209 1.187 0.813 0.634 0.546 0.455 0.398 23 1.242 0.893 0.674 0.582 0.590 0.452 22 1.499 1.04 0.765 0.663 0.68 0.527


Conductor Size

(AWG)


1 2-7 8 -19 20 - 37 38 - 61 62-91 92 - 192

26 2.424 1.227 0.874 0.677 0.572 0.554 NA 24 2.732 1.461 1.009 0.782 0.674 0.561 0.478 23 1.531 1.105 0.834 0.718 0.718 0.549 22 3 1.857 1.284 0.952 0.822 0.826 0.631




Conductor Size

(AWG)


1 2-7 8 -19 20 - 37 38 - 61 62-91 92 - 192

26 2.796 1.417 1.015 0.784 0.665 0.642 NA 24 3.172 1.692 1.174 0.907 0.781 0.651 0.549 23 1.775 1.284 0.968 0.831 0.823 0.628 22 2.158 1.489 1.11 0.955 0.947 0.717

Configurations where only ½ of the Conductors are Powered

INTRODUCTION

Some implementations of remote powering over LAN cable utilize 2-pair powering schemes as shown in the following diagrams. These powering methods are still widely used.

As can be seen from the diagrams, these schemes utilize only 4 conductors in the cable (out of 8) to carry current. As a result, there is less heat generated in each cable for the same amount of current per conductor. This would imply that the 4 conductors could each carry more current than each of the 8 conductors in the 4-pair power configuration to get the same heating effect. However, ½ the number of conductors carrying current does not translate to twice the current since the heating effect is related to the current squared.

ASSUMPTIONS & CALCULATIONS

Cable heating is a result of power dissipation given by the formula P= I2 x R

To make things simple, the following assumptions are made:



The power dissipation is the same for both configurations to get the same temperature. (There might be a hotter temperature “hot-spot” on the individual conductor since it is carrying more current but in general the temperature rise on the cable is due to the trapped heat rather than the individual conductor temperature.

The dc resistance would remain roughly the same for both scenarios. (It will be slightly higher for the 4-conductor scenario since the individual conductor will be warmer but the effect will be very small.)

Given these assumptions: P8 = P4 = Power per cable (assume same for both) I8 = Current for each conductor with 8 conductors energized I4 = Current for each conductor with 4 conductors energized R = DC Resistance of each conductor (assume same for both)

For 8 conductors energized: P8= I8

2 x R x 8 (8 conductors) For 4 conductors energized: P4= I4

2 x R x 4 (4 conductors) or I4 = SQRT (P4/(R x 4)) Since the power is assumed to be the same, the formula for 8 conductor power, P8, can be substituted for P4 to get a formula for I4:

I4 = SQRT (P8/(R x 4)) = SQRT ((I82 x R x 8)/(R x 4)) = SQRT (I8

2 x 2)

Calculating I4 for a number of different I8 currents we get the following along with a “factor” for each.

I8 I4 Factor (Factor = I4 / I8)

3 4.2426 1.4142 2 2.8284 1.4142 1.3 1.8385 1.4142 .6 .8485 1.4142 .3 .4243 1.4142 The factors are consistent, as would be expected.



TESTING & DATA

To validate the calculations and assumptions, tests were performed on a 61 cable bundle mounted in metal conduit and a 91 cable bundle mounted in Schedule 40 PVC conduit with 8 conductors carrying current. The tests were repeated with no changes to the test set-ups with 4 conductors carrying current. The results with best-fit trendline curves are shown below.



The curves permit the identification of the current that would yield a particular temperature.

For accuracy, rather than visually use the graphs to determine the current value, the formulas for the best-fit polynomial trendlines developed from the data are used with an iterative methodology to solve for “x” at various target temperatures “y”.

The following tables were generated for various target temperatures:

The “Factor” is the ratio of the current for the 4-conductor tests divided by the current for the 8-conductor tests.

SUMMARY

The data indicates that a factor of approximately 1.4 would be valid to estimate how much additional current could be carried by a 4-pair cable when only ½ of the conductors are powered.



Effects of Current

The data shows that in many cases, very small increases in conductor current resulted in large increases in measured temperatures.



Different Installation Methods

This graph shows an example of how different installation configurations affect the measured temperatures.

Photographs of Different Installation Configurations





Enclosing Cables

The data shows that enclosing cables has a dramatic effect on the measured temperatures. These graphs show the difference between open cable and a cable enclosed in conduit. It can be seen that for the entries on the far right there is no data for the enclosed cables. This is due to the temperatures exceeding the physical limits of the insulation materials in the enclosed scenario.



The data shows that sometimes different enclosed installations only made a minor difference in the measured temperatures.

The following comparison shows the same cable in open air, in a 4” X 4” closed cable routing assembly and in 4” schedule 40 PVC conduit. As expected the data shows that enclosing the cable results in considerably higher temperatures. However, there is not much difference between the installation in the 4” X 4” enclosed cable routing assembly and the 4” schedule 40 plastic conduit as shown by the overlapping curves and the data plotted on the column graph. The data shows that the 4” PVC conduit resulted in slightly higher temperatures. This is expected since the volume of the cable routing assembly is slightly larger than the conduit allowing for some additional heat dissipation from the cable bundle.



Installation Orientation

Since cables can be installed in any orientation, a comparison test was run on Cat 5e, 24 AWG cable in an open wire style cable tray. The test configuration consisted of 576 cables filling the tray with 18 layers of 32 cables. The cables were energized with 0.5 amperes per conductor with all conductors carrying current. The exact test set-up was used for both tests. Only the orientation was changed.



Summary

The results indicate very little difference between the horizontal and vertical orientations, with no significant difference on the cables at the center of the tray bundle (CH 14 through CH 16).



Firestop

When trying to compare the effects of adding firestop to cable bundles in metallic conduit, we came across variations that did not appear to be attributable to the addition of the firestop. For example, several of the tests showed that temperatures were lower for the configurations with the firestop. This would not be expected since the firestop prevents heat from escaping at the ends of the conduit. This was more pronounced for smaller bundle configurations.





Especially for the smaller bundles or single cables, it appears that the unexpected temperatures are the result of a heat-sinking effect where a cable contacts the conduit and the relative position of the thermocouples to these points affects the temperature readings. This would not be as pronounced with larger bundles which would have a more consistent lay and where the thermocouples are buried deep within the bundle. Because different cable bundles were used due to cable damage when the original open-end test was run to cable destruction, the cable lay inside of the conduit was likely different providing a different heat-sinking profile.

To check this, tests were performed on a single cable and a 7 cable bundle in metal conduit. Each test was first run without firestop. After thermal stabilization, firestop was carefully added without disturbing the cable. Temperatures were again allowed to stabilize and the results recorded. The data showed essentially no difference in the temperatures. This was consistent with the larger cable bundles where the lay / heat sinking effects did not appear to be significant. In these cases also, the data showed that adding firestop had little or no effect on the measured temperatures.



SUMMARY

The data shows that the addition of firestop at the ends of a 6 ft. conduit does not significantly affect the temperatures near the center 3 feet of the cable. Most of the heat is trapped at the center of the conduit in either case.



Cable Comparisons

The data shows that the cable design and construction has as much effect on the temperature rise as AWG size. These comparisons show some examples.





Cable Configurations

These tests were performed to determine the difference in measured temperatures (if any) between a “perfect” hexagonal bundle and a more random circular bundle.



LP Cables

As a result of the public inputs and resulting proposed first revisions to the NEC, a need was identified to develop requirements for a special-use cable that could be used as an alternative to traditional cables. Where the ampacity tables were sufficient for existing installations and new installations where the use of traditional cables was desirable, it was recognized that cables could be designed specifically to handle powering over communications cables without all of the limitations necessary for cables of unknown heating and heat dissipating characteristics. The objective, then, was to develop requirements that would permit a cable to be identified specifically for this type of installation and use.

It has been well established that cable heating can be managed via:

– Increased AWG size – Cable design – Material selection – Installation Practices

It was less clear how the interaction of these elements might affect a cable’s ability to handle increasing current levels. For example, there was little data available showing how changing a cable’s construction without changing the AWG size might affect temperatures or how variations in the installation might affect the temperatures for the same cable.

Obtaining data on these variations was necessary to determine how an “LP” cable might be evaluated. The following tests were identified as being critical in this endeavor:

Different Installations. Testing the same cable in various installation configurations to gain a better understanding of how bundle size and routing (open air, conduit, cable trays, cable routing assemblies, etc.) affects temperature

Orientation. Determine the effects of horizontal vs. vertical orientation on cable temperature in a bundle.

Cable Comparison. Test different cable types and constructions under the same installation and use conditions to obtain comparison data to better understand the effects of cable design on temperature.

Test Variations. Study what test variations have on temperature rise and under what conditions. For example, how does current increase affect temperatures or the effects of different size conduits.



LP CABLE REQUIREMENTS

As part of the fact-finding investigation, UL LLC has undertaken the development of a method for determining the ability of a cable to carry current under reasonable worse-case installation conditions including bundling of large numbers of cables, enclosing the cables in raceways, cable routing assemblies or conduit and elevated ambient temperatures. This effort has resulted in the test procedure described in APPENDIX D, “Cable Heating Test”.



SUMMARY

In consideration of the fact-finding character of the investigation, the foregoing Report is to be construed as information only and should not be regarded as conveying any conclusion or recommendations on the part of Underwriters Laboratories Inc. regarding the acceptability of the construction or performance of the product for recognition by any code or standard or for any other purpose.

The investigation resulted in the development of data in support of comments / proposals related to including more extensive ampacity tables in the NEC to better manage powering over LAN cable systems.

The investigation has identified that for certain powering over LAN cable installations with power levels exceeding 60 watts, overheating of the cables will occur.

Cable heating can be managed via:

Increased AWG size Cable design Material selection Installation Practices

The investigation produced data leading to the development of testing requirements for “-LP” cables.

Randy Ivans Program/Project Manager Wire and Cable Commercial & Industrial UL LLC. Anthony Tassone PE Principal Engineer (PDE) Wire & Cable Commercial & Industrial UL LLC.



APPENDIX A - CABLE DETAILS



Number of pages in this package ____ [including additional pages __-__] (Fill in when using printed copy as record)

TESTS TO BE CONDUCTED:

Test No.

Done3 Test Name

[ ] Comments/Parameters [x] Tests Conducted by2 [ ] Link to separate data files4

1 X DETAILED EXAMINATION: 5E 24AWG

Tim Falvey 2015-09-01

2 X DETAILED EXAMINATION: 5E 26AWG

Michael Askin 2015-09-02

3 X DETAILED EXAMINATION: 6 R 23AWG


4 X DETAILED EXAMINATION: 6 P 23AWG


5 X DETAILED EXAMINATION: 6 P 22AWG


6 X DETAILED EXAMINATION: 6A 23AWG


[X] Safety Certification - Unless specified otherwise in the individual Methods, the tests shall be conducted under the following ambient conditions. Confirmation of these conditions shall be recorded at the time the test is conducted. Ambient Temperature, C 23 ± 5

Relative Humidity, % 50 ± 20

Barometric Pressure, mBar NA



TEST LOCATION: (To be completed by Staff Conducting the Testing)

[x]UL or Affiliate []WTDP

[]CTDP []TPTDP []TCP []PPP

[]WMT []TMP []SMT

Company Name: UL LLC

Address: 1285 Walt Whitman Rd. Melville, NY TEST EQUIPMENT INFORMATION

[x] UL test equipment information is recorded on Meter Use in UL’s Laboratory Project Management (LPM) database. TEST SAMPLE IDENTIFICATION:

The table below is provided to establish correlation of sample numbers to specific product related information. Refer to this table when a test identifies a test sample by "Sample No." only.

Sample Card No.

Date Received

[] Test No.+

Sample No. Manufacturer, Product Identification and Ratings

XXXX 1 1 CAT5E 24AWG UTP (YELLOW)

2 2 CAT5E 26AWG FTP SHIELDED PATCH (LT GREY)

3 3 CAT6 23AWG UTP RISER CMR (BLUE)

4 4 CAT6 23AWG UTP PLENUM CMP (WHITE)

5 5 CAT6 22AWG UTP PLENUM CMP (BLUE)

6 6 CAT6A 23AWG SHIELDED PLENUM (DARK GREY)

+ - If Test Number is used, the Test Number or Numbers the sample was used in must be identified on the data sheet pages or on the Data Sheet Package cover page.



DETAILED EXAMINATION: UL 444, Clause 5

Sample No. 1 Ambient Temp.: 24C Humidity: 61% RH

Note: All units are expressed in terms of: [x] Inches [ ] mm

[x] Identification

Print Type: None Ink Indent Tape Other:

Print Content:

0394 FEET CAT-5E GENERAL CABLE J 2001345 CMR C(ETL)US 4PR 24AWG 75C GENSPEED 5000 IWC---VERIFIED BY UND LAB INC ONLY TO ANSI/TIA-568C.2 CAT-5E--- TESTED TO 350MHZ 03-14 302136F2 PAT 5767441 CAT-5E

Print Interval: 24.25 inches

No. of Insulated Conductors 8 No. Of Bare Conductors 0

Brief Assembly Description: Jacket, 4 pairs of solid-insulated conductors, rip cord



DETAILED EXAMINATION (Sample #1): (CONT’D) UL 444, Clause 5 Ambient Temp.: 24C Humidity: 61% RH

Note: If additional space is required please continue under “attached Component” section

[x] Jacket Overall Jacket

Inner Jacket 1

Inner Jacket 2

Inner Jacket 3

Color Yellow n/a n/a n/a

Overall cable diameter, in. .190 n/a n/a n/a

Core diameter under jacket, in. .156 n/a n/a n/a

Major axis, in. n/a n/a n/a n/a

Minor axis, in. n/a n/a n/a n/a

Average thickness, in. .016 n/a n/a n/a

Min. thickness at any point, in. .015 n/a n/a n/a

Minimum thickness after rip, in. n/a n/a n/a n/a

Average web thickness, in. n/a n/a n/a n/a

Average web width, in. n/a n/a n/a n/a

[ ] Note: If ave. or min. point jacket thickness exceeds / is less than the

following requirement contact engineer before proceeding:

Min Ave. , in. Min Point , in.




Sample No.

[ ] Armor [x] Assembly

Type of Armor n/a Lay of conductors, in. .5

Convolutions per inch / mm n/a Lay of conductor pairs, in. 5.7

Diameter over armor, in. n/a Lay of members, in. n/a

Diameter under armor, in. n/a

Strip width, in. n/a

Average thickness, in. n/a

Min. thickness at any point, in. n/a

[ ] Braid Parameters Braid 1 Braid 2 Braid 3

Type of braid n/a n/a n/a

Strand diameter, in. n/a n/a n/a

No. ends n/a n/a n/a

No. carriers n/a n/a n/a

Picks per inch / mm n/a n/a n/a

Core Dia. under braid inch/mm n/a n/a n/a

Calculated % coverage n/a n/a n/a



DETAILED EXAMINATION (Sample #1): (CONT’D) UL 444, Clause 5 Ambient Temp.: C Humidity: % RH [ ] Tapes, binders, rods, rip cords, and fillers

Type n/a n/a n/a n/a n/a

Thickness, in. n/a n/a n/a n/a n/a

Width, in. n/a n/a n/a n/a n/a

Lap, in. n/a n/a n/a n/a n/a

Overall diameter, in. n/a n/a n/a n/a n/a

Helical/longitudinal n/a n/a n/a n/a n/a

Calculated % coverage n/a n/a n/a n/a n/a

Count n/a n/a n/a n/a n/a

Major/minor axis, in. n/a n/a n/a n/a n/a

Ripcord present? n/a n/a n/a n/a n/a Sample No.

[x] Insulation Conductor Conductor Conductor Conductor

Color ORANGE n/a n/a n/a

Separator tape present? no n/a n/a n/a

Average thickness, in. .0075 n/a n/a n/a

Minimum thickness at any point, in. .006 n/a n/a n/a

Minimum thickness after rip, in. n/a n/a n/a n/a

Average web thickness, in. n/a n/a n/a n/a

Average web width, in. n/a n/a n/a n/a

[ ] Insulation Covering

Color n/a n/a n/a n/a

Average thickness, in. n/a n/a n/a n/a

Minimum thickness at any point, in. n/a n/a n/a n/a

[ ] Note: If ave. or min. point insulation thickness exceeds/is less than

the following requirement contact engineer before proceeding:




DETAILED EXAMINATION: (CONT’D) UL 444, Clause 5 Ambient Temp.: 24C Humidity: 61% RH

[x] Conductor Conductor Conductor Conductor Conductor

1 2 3 4

Type (i.e. Al, Cu, etc.) cu n/a n/a n/a

Coating present? no n/a n/a n/a

Diameter of solid conductor, in. .01975 n/a n/a n/a

Diameter over insulation, in. .0346 n/a n/a n/a

Number of strands n/a n/a n/a n/a

Strand diameter, in. n/a n/a n/a n/a

Lay of strands, in. n/a n/a n/a n/a

Circular Mil Area (CMA) n/a n/a n/a n/a

AWG size 24 n/a n/a n/a

Ambient Temp.: 24C Humidity: 61% RH

METHOD: UL 444, Clause 4.1 – 4.11

Solid Conductor:

Specimen: #1

Min. #1 Diameter, in. .0197

Max. #1 Diameter, in. .0198





Average Conductor Diameter, in. .01975

Conductor AWG Size 24



DETAILED EXAMINATION (Sample #1): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, CONDUCTOR: Ambient Temp.: 24C Humidity: 61% RH

Sample No.______

[x] Conductor DC Resistance

Length of specimen (ft/meter) 1

Conductor resistance (measurement 1), ohms/kft 26.85




Minimum of 4 measurements, ohms/kft 26.85

Temperature of conductor, C 24

Multiplying factor for adjustment to resistance at ____C *

Conductor resistance adjusted to ____C, Ohms/1000 (ft/meter) *

*Resistomat calculated at 20c



DETAILED EXAMINATION (Sample #1): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, INSULATION:



Insulation:

Specimen: #1

Thickness: Min #1, in. .006

Max #1, in. .009

Average Thickness, in. .0075

Outside diameter: Min #1, in. .035

Max #1, in. .035

Min #2, in. .034

Max #2, in. .035

Min #3, in. .034

Max #3, in. .035

Average Outside Diameter, in. .0346



DETAILED EXAMINATION (Sample #1): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, JACKET:



Jacket:

Specimen: #1


Max #1, in. .017



Max #1, in. .185

Min #2, in. .189

Max #2, in. .201

Min #3, in. .175

Max #3, in. .205


Core diameter: Min #1, in. .149

Max #1, in. .151

Min #2, in. .154

Max #2, in. .169

Min #3, in. .140

Max #3, in. .171

Average Core Diameter, in. .156





Note: All units are expressed in terms of: [X] Inches [ ] mm

[X] Identification


Print Content: YFC FTP CAT.5E 350MHZ PATCH ISO/IEC 11801 7 EN 50288 3P

CONFORMS TO GIGABIT ETHERNET 26AWGX4 TYPE CMX(UL) C(UL) CMH E164469-F5

Print Interval: 48.5 Inches


Brief Assembly Description: JKT, POLY AL WRAP, DRAIN WIRE, CLEAR POLY WRAP,

8 INSULATED STRANDED CONDUCTORS





[X] Jacket Overall Jacket

Inner Jacket 1

Inner Jacket 2

Inner Jacket 3

Color GREY

Overall cable diameter, in. .230

Core diameter under jacket, in.

.

183

Major axis, in. -

Minor axis, in. -

Average thickness, in. .023

Min. thickness at any point, in. .022

Minimum thickness after rip, in. -

Average web thickness, in. -

Average web width, in. -







Sample No.

[ ] Armor [X] Assembly

Type of Armor Lay of conductors, in. .375

Convolutions per inch / mm Lay of conductor pairs, in. 4.0

Diameter over armor, in. Lay of members, in. -

Diameter under armor, in.

Strip width, in.

Average thickness, in.

Min. thickness at any point, in.



DETAILED EXAMINATION (Sample #2): (CONT’D) UL 444, Clause 5 Ambient Temp.: 25C Humidity: 58% RH [X] Tapes, binders, rods, rip cords, and fillers

Type POLY AL

WRAP CLEAR POLY

Thickness, in. .0009 .0006

Width, in. .750 .813

Lap, in. .188 .250

Overall diameter, in.

Helical/longitudinal HELI HELI

Calculated % coverage TBD TBD

Count 1 1

Major/minor axis, in. - -

Ripcord present? - -

Sample No.

[X] Insulation Conductor Conductor Conductor Conductor

Color BLUE

Separator tape present? NO


Minimum thickness at any point, in. .008





Color


Minimum thickness at any point, in.







[X] Conductor Conductor Conducto

r Conductor Conductor

1 2 3 4

Type (i.e. Al, Cu, etc.) Cu

Coating present? NO

Diameter of solid conductor, in. .018

Diameter over insulation, in. .036

Number of strands 7

Strand diameter, in. .0060

Lay of strands, in. .438

Circular Mil Area (CMA) 252

AWG size 26 Ambient Temp.: 25C Humidity: 58% RH



DETAILED EXAMINATION (Sample #2): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, ROUND CONDUCTOR: (CONT’D) Ambient Temp.: 25C Humidity: 58% RH


Stranded Conductor:

Specimen: #1

Number of Strands 7

Strand 1 – Min. Diameter, in. .00605

Max. Diameter, in. .0061













Average Strand Diameter, in. .0060

Total conductor area, in2 / mm2 252




DETAILED EXAMINATION (Sample #2): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, insulation: Ambient Temp.: 25C Humidity: 58% RH


Insulation:

Specimen: #1


Max #1, in. .010



Max #1, in. .03585

Min #2, in. .03601

Max #2, in. .03601

Min #3, in. .03641

Max #3, in. .03643




DETAILED EXAMINATION (Sample #2): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, JACKET: Ambient Temp.: 25C Humidity: 58% RH


Jacket:

Specimen: #1


Max #1, in. .024



Max #1, in. .227

Min #2, in. .228

Max #2, in. .228

Min #3, in. .229

Max #3, in. .242



Max #1, in. .182

Min #2, in. .183

Max #2, in. .183

Min #3, in. .183

Max #3, in. .184







[X] Identification


Print Content: CAT-6 GENERAL CABLE J 2001345 CMR C(ETL)US CMG 4PR 23AWG

GENSPEED 6 IWC VERIFIED BY UND LAB INC ONLY TO ANSI/TIA-568C.2 CAT-6

Print Interval: 24 inches


Brief Assembly Description: JKT, RIP CORD, FLAT FILLER, 8 INS CON






Inner Jacket 1

Inner Jacket 2

Inner Jacket 3

Color BLUE


Core diameter under jacket, in. .191

Major axis, in. -

Minor axis, in. -












Sample No.






Strip width, in.






Type FLAT

FILLER

Thickness, in. .0012

Width, in. .171

Lap, in. -

Overall diameter, in. -

Helical/longitudinal HELI

Calculated % coverage -

Count 1

Major/minor axis, in. -

Ripcord present? -

Sample No.


Color BLUE








Color











1 2 3 4


Coating present? NO



Number of strands -

Strand diameter, in. -

Lay of strands, in. -

Circular Mil Area (CMA) -



Solid Conductor:

Specimen: #1











DETAILED EXAMINATION (Sample #3): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, INSULATION: Ambient Temp.: 25C Humidity: 58% RH


Insulation:

Specimen: #1


Max #1, in. .009



Max #1, in. .03825

Min #2, in. .03828

Max #2, in. .03837

Min #3, in. .03839

Max #3, in. .03882






Jacket:

Specimen: #1


Max #1, in. .020



Max #1, in. .226

Min #2, in. .228

Max #2, in. .229

Min #3, in. .229

Max #3, in. .231



Max #1, in. .190

Min #2, in. .190

Max #2, in. .192

Min #3, in. .193

Max #3, in. .194







[X] Identification


Print Content: CAT-6 GENERAL CABLE J CMP 90C C(UL)US 4PR 23AWG GENSPEED

6 PLENUM VERFIED (UL) ANSI/TIA-568C.2 CAT6



Brief Assembly Description: JKT, RIP CORD, FLAT FILLER, 8 INS CON






Inner Jacket 1

Inner Jacket 2

Inner Jacket 3

Color WHITE



Major axis, in. -

Minor axis, in. -












Sample No.

[ ] Armor [x] Assembly





Strip width, in.




Type of braid

Strand diameter, in.

No. ends

No. carriers

Picks per inch / mm

Core Dia. under braid inch/mm

Calculated % coverage




Type FLAT

Thickness, in. .012

Width, in. .173

Lap, in. -



Calculated % coverage -

Count 1


Ripcord present? -

Sample No.


Color BLUE








Color











1 2 3 4


Coating present? NO



Number of strands -






Solid Conductor:

Specimen: #1











DETAILED EXAMINATION (Sample #4): (CONT’D) UL 444, Clause 5 DETAILED EXAMINATION, insulation: Ambient Temp.: 25C Humidity: 58% RH


Insulation:

Specimen: #1


Max #1, in. .010



Max #1, in. .03894

Min #2, in. .03902

Max #2, in. .03907

Min #3, in. .03916

Max #3, in. .03980






Jacket:

Specimen: #1


Max #1, in. .016



Max #1, in. .208

Min #2, in. .208

Max #2, in. .209

Min #3, in. .212

Max #3, in. .216



Max #1, in. .177

Min #2, in. .177

Max #2, in. .178

Min #3, in. .181

Max #3, in. .186







[X] Identification


Print Content: GenSPEED EfficienC MAX CAT 6 ENHANCED POE++ E105765-L CMP

(UL) C(UL) 4PR 22AWG 90C VERIFIED (UL) ANSI/TIA-568C.2 CAT6



Brief Assembly Description: JKT, RIP CORD, FLAT FILLE, 8 INS CON






Inner Jacket 1

Inner Jacket 2

Inner Jacket 3

Color BLUE



Major axis, in. -

Minor axis, in. -












Sample No.

[ ] Armor [ ] Assembly





Strip width, in.




Type of braid

Strand diameter, in.

No. ends

No. carriers

Picks per inch / mm

Core Dia. under braid inch/mm

Calculated % coverage




Type FLAT

Thickness, in. .011

Width, in. .173

Lap, in. -



Calculated % coverage TBD

Count 1


Ripcord present? -

Sample No.


Color BLUE








Color











1 2 3 4


Coating present? NO



Number of strands -






Solid Conductor:

Specimen: #1













Insulation:

Specimen: #1


Max #1, in. .010



Max #1, in. .04155

Min #2, in. .04218

Max #2, in. .04224

Min #3, in. .04224

Max #3, in. .04262






Jacket:

Specimen: #1


Max #1, in. .016



Max #1, in. .219

Min #2, in. .220

Max #2, in. .222

Min #3, in. .224

Max #3, in. .227



Max #1, in. .191

Min #2, in. .191

Max #2, in. .194

Min #3, in. .195

Max #3, in. .199







[X] Identification


Print Content: GENERAL CABLE L GENSPEED 10MTP CATEGORY 6A 4PR/23AWG UTP

PLENUM CABLE C(UL)US CMP 90C VERIFIED(UL) ANSI/TIA-568C.2 CAT-6A PAT 5767441,

8354590, 8183462 10MTP.US



Brief Assembly Description: JKT, POLY AL WRAP, POLYESTER WRAP, STAR FILLER,

8 INS CON






Inner Jacket 1

Inner Jacket 2

Inner Jacket 3

Color GREY



Major axis, in. -

Minor axis, in. -












Sample No.






Strip width, in.






Type

POLY AL WRAP

WOVEN POLYESTER

WRAP

Thickness, in. .0032 .0063

Width, in. 1.0 .750

Lap, in. .250 .188

Overall diameter, in. .239 .230

Helical/longitudinal HELI HELI

Calculated % coverage TBD TBD

Count 1 1

Major/minor axis, in. - -

Ripcord present? - -

Sample No.


Color BLUE








Color









[x] Conductor Conductor Conducto


1 2 3 4


Coating present? NO



Number of strands -






Solid Conductor:

Specimen: #1













Insulation:

Specimen: #1


Max #1, in. .011



Max #1, in. .042

Min #2, in. .042

Max #2, in. .043

Min #3, in. .043

Max #3, in. .043






Jacket:

Specimen: #1


Max #1, in. .017



Max #1, in. .274

Min #2, in. .283

Max #2, in. .283

Min #3, in. .286

Max #3, in. .287



Max #1, in. .244

Min #2, in. .250

Max #2, in. .252

Min #3, in. .253

Max #3, in. .255




DETAILED EXAMINATION (Sample #6): (CONT’D) UL 444, Clause 5 STAR FILLER DIMENSIONS:


d Thickness at any point, mils ______41______ w Average Thickness, mils _____20_______ Minimum Thickness at any point, mils _____17_______ Maximum Thickness at any point, mils _____24_______ l Average Thickness, mils ______70______ Minimum Thickness at any point, mils _____65_______ Maximum Thickness at any point, mils _____74_______



APPENDIX B - TEMPERATURE TEST DATA



ThermocouplePlacement‐General

TC6 and TC7 are at the center of the cable bundle length. TC7 is inside the jacket on the individual wire insulation. TC6 is on the outside of the cable jacket.



TEMPERATURE TEST DATA












































































































APPENDIX C - DATA for NEC TABLES



































APPENDIX D - CABLE HEATING TEST

The proposed requirements for the UL Standard(s) for Safety are to be considered as tentative and are only meant to demonstrate the form and content of such a proposal. They have not been presented to the relevant industry nor subjected to UL's standards development procedure. The requirements are shown only as examples and are based on the results given in this Report. 7.24 (NEW) Cable Heating Test

77.24.1 When tested as described in this section, the temperatures measured on the insulation and jacket of the cables, after being corrected to an ambient of 45oC, shall not exceed the temperature rating of the cable.

7.24.2 The cables shall be arranged in a bundle consisting of 192 cables and electrically connected in series to a power supply capable of providing the rated current marked as part of the LP rating. The inner 37 cables shall be arranged as shown in Figure 4. The remaining cables shall be evenly distributed in a random fashion to form a 192 cable bundle. The bundle shall be placed in a 6 foot long (1.83 m) commercially available non-metallic conduit (Schedule 40) with the minimum diameter needed to install the bundle without putting pressure on the cables. Each end of the conduit shall be filled with insulation.

7.24.3 The temperatures shall be measured on the outer jacket and conductor insulation of the center cable at the midpoint of the cable. In addition, temperatures shall be measured on the jacket and conductor insulation on the center cable two feet (0.6 m) on each side of center thermocouple.

7.24.4 Temperatures are to be measured by means of thermocouples consisting of iron and constantan wires not larger than 24 AWG (0.21 mm2) and not smaller than 30 AWG (0.05 mm2). When thermocouples are used in determining temperatures in electrical equipment, it is common practice to employ thermocouples consisting of 30 AWG iron and constantan wires with a potentiometer-type of indicating instrument. This equipment is to be used whenever a referee measurement of temperature is necessary.



7.24.5 The thermocouples and related instruments are to be accurate and calibrated in accordance with standard laboratory practice. The thermocouple wire is to conform to the requirements specified in the Tolerances on Initial Values of EMF versus Temperature tables in the Standard Specification and Temperature-Electromotive Force (emf) Tables for Standardized Thermocouples, ANSI/ASTM E230/E230M.

7.24.6 A thermocouple junction and adjacent thermocouple lead wire are to be securely held in good thermal contact with the surface of the material whose temperature is being measured. In most cases, acceptable thermal contact results from securely taping or cementing the thermocouple in place

Example of Cable Heating Test


725.179 Listing and Marking of Class 2, Class 3, and Type PLTC Cables.

Class 2, Class 3, and Type PLTC cables, installed as wiring methods within buildings, shall be listed as resistant to the spreadof fire and other criteria in accordance with 725.179(A) through (H I ) and shall be marked in accordance with 725.179(I J ).

(A) Types CL2P and CL3P.

Types CL2P and CL3P plenum cable shall be listed as suitable for use in ducts, plenums, and other space for environmental airand shall be listed as having adequate fire-resistant and low-smoke producing characteristics.

Informational Note: One method of defining a cable that is low-smoke producing and fire-resistant is that the cableexhibits a maximum peak optical density of 0.50 or less, an average optical density of 0.15 or less, and a maximum flamespread distance of 1.52 m (5 ft) or less when tested in accordance with NFPA 262-2015 , Standard Method of Test forFlame Travel and Smoke of Wires and Cables for Use in Air-Handling Spaces.

(B) Types CL2R and CL3R.

Types CL2R and CL3R riser cables shall be marked as Type CL2R or CL3R, respectively, and be listed as suitable for use in avertical run in a shaft or from floor to floor and shall be listed as having fire-resistant characteristics capable of preventing thecarrying of fire from floor to floor.

Informational Note: One method of defining fire-resistant characteristics capable of preventing the carrying of fire fromfloor to floor is that the cables pass the requirements of ANSI/UL 1666-2012, Test for Flame Propagation Height ofElectrical and Optical-Fiber Cable Installed Vertically in Shafts.

(C) Types CL2 and CL3.

Types CL2 and CL3 cables shall be marked as Type CL2 or CL3, respectively, and be listed as suitable for general-purposeuse, with the exception of risers, ducts, plenums, and other space used for environmental air, and shall be listed as resistant tothe spread of fire.

Informational Note: One method of defining resistant to the spread of fire is that the cables do not spread fire to the top ofthe tray in the UL flameexposure, verticaltrayflametest in ANSI/UL 1685-2010, Standard for Safety for Vertical-TrayFire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables. The smoke measurements in the testmethod are not applicable.

Another method of defining resistant to the spread of fire is for the damage (char length) not to exceed 1.5 m (4 ft 11 in.)when performing the CSA verticalflametestfor— cables in cabletrays, as described in CSA C22.2 No. 0.3-M-2001, TestMethods for Electrical Wires and Cables.

(D) Types CL2X and CL3X.

Types CL2X and CL3X limited-use cables shall be marked as Type CL2X or CL3X, and be listed as suitable for use in dwellingsand raceways and shall be listed as resistant to flame spread.

Informational Note: One method of determining that cable is resistant to flame spread is by testing the cable to the VW-1(vertical wire) flame test in ANSI/UL 1581-2011, Reference Standard for Electrical Wires, Cables and Flexible Cords.

(E) Type PLTC.

Type PLTC nonmetallic-sheathed, power-limited tray cable shall be listed as being suitable for cable trays and shall consist of afactory assembly of two or more insulated conductors under a nonmetallic jacket. The insulated conductors shall be 22 AWGthrough 12 AWG. The conductor material shall be copper (solid or stranded). Insulation on conductors shall be rated for 300volts. The cable core shall be two or more parallel conductors, one or more group assemblies of twisted or parallel conductors,or a combination thereof. A metallic shield or a metallized foil shield with drain wire(s) shall be permitted to be applied over thecable core, over groups of conductors, or both. The cable shall be listed as resistant to the spread of fire. The outer jacket shallbe a sunlight- and moisture-resistant nonmetallic material. Type PLTC cable used in a wet location shall be listed for use in wetlocations or have a moisture-impervious metal sheath.

Exception No. 1: Where a smooth metallic sheath, continuous corrugated metallic sheath, or interlocking tape armor is appliedover the nonmetallic jacket, an overall nonmetallic jacket shall not be required. On metallic-sheathed cable without an overallnonmetallic jacket, the information required in 310.120 shall be located on the nonmetallic jacket under the sheath.

Exception No. 2: Conductors in PLTC cables used for Class 2 thermocouple circuits shall be permitted to be any of thematerials used for thermocouple extension wire.

Informational Note: One method of defining resistant to the spread of fire is that the cables do not spread fire to the top ofthe tray in the UL flameexposure, vertical trayflame test in ANSI/UL 1685-2010, Standard for Safety for Vertical-TrayFire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables. The smoke measurements in the testmethod are not applicable.

Another method of defining resistant to the spread of fire is for the damage (char length) not to exceed 1.5 m (4 ft 11 in.)when performing the CSA verticalflametest for— cables in cabletrays, as described in CSA C22.2 No. 0.3-M-2001, TestMethods for Electrical Wires and Cables.

(F) Circuit Integrity (CI) Cable or Electrical Circuit Protective System.


1826 of 2079 10/1/2015 11:02 AM

Cables that are used for survivability of critical circuits under fire conditions shall meet either 725.179(F)(1) or (F)(2) as follows:

(1) Circuit Integrity (CI) Cables.

Circuit Integrity (CI) cables, specified in 725.179(A), (B), (C), and (E), and used for survivability of critical circuits, shall have theadditional classification using the suffix “CI.” Circuit integrity (CI) cables shall only be permitted to be installed in a racewaywhere specifically listed and marked as part of an electrical circuit protective system as covered in 725.179(F)(2).

(2) Electrical Circuit Protective System.

Cables specified in 725.179(A),(B), (C), (E), and (F)(1) that are part of an electrical circuit protective system shall be identifiedwith the protective system number and hourly rating printed on the outer jacket of the cable and installed in accordance with thelisting of the protective system.

Informational Note No. 1: One method of defining circuit integrity (CI) cable or an electrical circuit protective system is byestablishing a minimum 2-hour fire-resistive rating when tested in accordance with UL 2196-2012, Standard for Tests ofFire Resistive Cables.

Informational Note No. 2: UL guide information for electrical circuit protective systems (FHIT) contains information onproper installation requirements to maintain the fire rating.

(G) Class 2 and Class 3 Cable Voltage Ratings.

Class 2 cables shall have a voltage rating of not less than 150 volts. Class 3 cables shall have a voltage rating of not less than300 volts. Class 2 and Class 3 cables shall have temperature rating of not less than 60°C (140°F).

(H) Class 3 Single Conductors.

Class 3 single conductors used as other wiring within buildings shall not be smaller than 18 AWG and shall be Type CL3.Conductor types described in 725.49(B) that are also listed as Type CL3 shall be permitted.

Informational Note: One method of defining resistant to the spread of fire is that the cables do not spread fire to the top ofthe tray in the UL flameexposure, verticaltrayflame test in ANSI/UL 1685-2010, Standard for Safety for Vertical-TrayFire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables. The smoke measurements in the testmethod are not applicable.

Another method of defining resistant to the spread of fire is for the damage (char length) not to exceed 1.5 m (4 ft 11 in.)when performing the CSA verticalflame test for— cables in cable trays, as described in CSA C22.2 No. 0.3-M-2001, TestMethods for Electrical Wires and Cables.

(I) Limited Power Cables. Limited power (LP) cables shall be listed as suitable for carrying power and data circuitsup to a specified current limit for each conductor without exceeding the temperature rating of the cable where the cableis installed in cable bundles in free air or enclosed. The cables shall be marked with the suffix “-LP(xxA), where the xx isthe current limit in amperes per conductor.

Informational Note: The “(xxA)” in the text is the ampacity (in Amperes) of each conductor in a cable. For example, 1ampere Class 2 limited-power cables shall be marked CL2-LP (1.0) , CL2R-LP (1.0A), or CL2-LP (1.0A) , as applicable .

(J) Marking.

Cables shall be marked in accordance with 310.120(A)(2), (A)(3), (A)(4), (A)(5), and Table 725.179(K) . Voltage ratings shall notbe marked on the cables. Temperature rating shall be marked on the jacket of Class 2 and Class 3 cables that have atemperature rating exceeding 60°C (140°F).

Informational Note: Voltage markings on cables may be misinterpreted to suggest that the cables may be suitable forClass 1 electric light and power applications.

Exception: Voltage markings shall be permitted where the cable has multiple listings and a voltage marking is required for oneor more of the listings.

Table 725.179(K J ) Cable Marking

Cable Marking Type

CL3P Class 3 plenum cable

CL2P Class 2 plenum cable

CL3R Class 3 riser cable

CL2R Class 2 riser cable

PLTC Power-limited tray cable

CL3 Class 3 cable

CL2 Class 2 cable

CL3X Class 3 cable, limited use

CL2X Class 2 cable, limited use

Informational Note: Class 2 and Class 3 cable types are listed in descending order of fire resistance rating, and Class 3cables are listed above Class 2 cables because Class 3 cables can substitute for Class 2 cables.



1827 of 2079 10/1/2015 11:02 AM


SPI_Fact_Finding_Report_2015-09_ul_spi_20150923-reduced_file_size.pdf

UL Fact Finding Report on Power over Local Area Network Type Cables (4-Pair Data / Communications Cables)


This Public Comment is one of a series on cable heating due to the transmission of power and data using cables that are typically installed in bundles, raceways, cable trays, or cable routing assemblies.

To aid the panel in evaluation this Public Comment, the resolved Public Input 1838 is show at the end of the substantiation. Note: References to other PI’s are omitted.

Where there is an accumulation of cables are used for the transmission of power and data and are in open air or enclosed, the current in the conductors generate heat. The temperature may increase a sufficient amount to cause degradation of the cable insulation. The listing and marking is based on an extensive fact finding investigation by Underwriter’s Laboratories. The fact finding report is included for reference.

The UL fact finding investigation shows that the ampacities listed in Table 725.144 are accurate for 4-pair cables without the “-LP” suffix. However, in actual installations the quantity of cables routed together are often greater than 192 cables. The “LP” suffix provides a safety margin for installation in any quantity. In addition, it is important that the current rating of the cable is equal to or less than the nameplate rating of the power source.

Further, 20 AWG was not tested as, presently, 22 AWG is the largest conductor that will fit into a RJ 45 connector. Extensive testing at UL LLC has shown that large bundles of 4-pair cables with 22 AWG or smaller conductors may exceed their temperature rating with all conductors carrying 1 ampere, which is well below the 1.67 ampere maximum current permitted in a 60 volt, 100 VA circuit.

See the attached UL Fact Finding Report on Power over Local Area Network Type Cables (4-Pair Data / Communications Cables) for supporting data.






Related Item

Public Input No. 2366-NFPA 70-2014 [New Section after 725.179(K)]



Organization: SPI

Affilliation: SPI

Street Address:

City:

State:

Zip:



1828 of 2079 10/1/2015 11:02 AM


(B) Types CL2R and CL3R.

Types CL2R and CL3R riser cables shall be marked as Type CL2R or CL3R, respectively, and be listed as suitable for use in avertical run in a shaft or from floor to floor and shall be listed as having fire-resistant characteristics capable of preventing thecarrying of fire from floor to floor. Optionally, Types CL2R and CL3R riser cables shall be permitted to be marked as Type CL2RST1 or CL3R ST1, respectively, if they are listed as having fire-resistant characteristics capable of preventing the carrying of firefrom floor to floor and also listed as exhibiting limited smoke characteristics.

Informational Note 1 : One method of defining fire-resistant characteristics capable of preventing the carrying of fire fromfloor to floor is that the cables pass the requirements of ANSI/UL 1666-2012, Test for Flame Propagation Height ofElectrical and Optical-Fiber Cable Installed Vertically in Shafts.

Informational Note 2 : One method of defining optional limited smoke characteristics for riser cables is that the cables

exhibit a peak smoke release rate not exceeding 0.40 m 2 /s and a total smoke released not exceeding 150 m 2 whentested in accordance with the requirements of CSA "Vertical Flame Test - Cables in Cable Trays," as described in CSAC22.2 No. 0.3-M-2009, Test Methods for Wires and Cables".


Please reconsider the action on this public input and accept the public comment. Smoke obscuration is a key fire safety problem.

The reason that this additional optional listing and informational note are important is that there is no information in any of the test methods for fire propagation of cables how to test for smoke in riser cables. Such information is neither included in UL 1666 nor in CSA FT4 nor in UL 1685. Therefore there can be no standardized way for a manufacturer to demonstrate that a specific type of riser cables has lower smoke than typical riser cables. This is very different from the case of general purpose (or cable tray) cables. Both UL 1685 and CSA FT4 contain information on how to obtain "limited smoke" (meaning reduced smoke) cables that are general purpose cables. Therefore I understand the panel's objections to include optional markings for these cables. However, unless the code provides a systematic and standard way to determine what is a "limited smoke riser cable" the optional markings will not be able to be generated adequately.

A key aspect of wire and cable fire performance is smoke emission since it is well known that lack of visibility and smoke are serious problems in fire. In the NEC there is a designation for "low smoke cables", which are plenum-rated cables. There is also an optional designation of limited smoke cables, which is not required but applies to cable tray cables (tested to UL 1685 or CSA FT4). Riser cables are cables that usually are found in concealed spaces and it would be important to offer an optional marking for limited smoke riser cables, to distinguish them from standard riser cables. This is particularly useful for riser cables because, typically, riser cables are made with insulation and jacket materials that are very similar to CSA FT4 cables and also with materials that do not quite exhibit the flame and smoke characteristics of plenum cables. Therefore, manufacturers of materials who try to achieve a plenum cable rating, and can't quite make it, will often make their material slightly less safe from the point of view of smoke emission, in order to be able to save costs. This new optional marking would permit manufacturers to provide cables with both limited smoke and the flame spread characteristics of riser cable. The choice of criterion for the limited smoke riser cables (and the choice of designation) is based on the ST1 designation associated with the CSA FT4 test, when smoke emission is assessed.

This public comment is being proposed for all instances of riser cables and not public comment is proposed for optional markings of general purpose cables.

Related Item





Street Address:

City:

State:

Zip:



1829 of 2079 10/1/2015 11:02 AM


(B) Ducts, Plenums, and Other Air-Handling Spaces.

Section 300.22 , where Power-limited and non-power-limited fire alarm cables installed in ducts or , plenums or other spacesused for environmental air shall comply with 300 .22.

Exception : As permitted in 760.53(B)(1) and (B)(2) and Table 760.154 . No. 1: Power-limited fire alarm cables selected inaccordance with Table 760.154 and installed in accordance with 760.135(B) shall be permitted to be installed in ductsspecifically fabricated for environmental air.

Exception No. 2: Power-limited fire alarm cables selected in accordance with Table 760.154 and installed in accordance with760.135(C) shall be permitted to be installed in other spaces used for environmental air (plenums).


The recommended text clarifies that 760.135 has explicit rules for power-limited fire alarm cables installed inducts [(760.135(B)] and other spaces use for environmental air (plenums) [760.135(C)].

The current text does not comply with section 3.1.4.1 of the NEC Style Manual which requires that exceptions shall be written in complete sentences. Acceptance of the recommended text will result in compliance with the NEC Style manual.

Related Item





Affilliation: BICSI

Street Address:

City:

State:

Zip:



1830 of 2079 10/1/2015 11:02 AM


(A) General.

Fire alarm circuits shall be installed in a neat workmanlike manner. Cables and conductors installed exposed on the surface ofceilings and sidewalls shall be supported by the building structure in such a manner that the cable will not be damaged bynormal building use. Such cables shall be supported by straps, staples, cable ties, hangers, or similar fittings designed andinstalled so as not to damage the cable. The installation shall also comply with 300.4(D). Metallic means of support for flexibleconduit and conductors shall be used in spaces above egress, which includes doorways, hallways, stairways, corridors,passageways, lobbies, landings, and equivalent spaces.

Informational note: Nonmetallic supports exhibit significant weakening and failure during fires which can affect the safety ofoccupants and emergency personnel entering and exiting buildings due to entanglement in fallen cable.


Emergency responders and building occupant safety is at risk during building fires because people can become entangled and trapped in cabling which hasfallen out of molten or failing plastic supports/raceway. Even if people can free themselves from fallen cabling, this takes time which is otherwise needed toexit the building or fulfill the objectives of emergency personnel. The frequency of emergency responders becoming trapped in fallen cabling has become socommon that firefighters have created and publicly distributed training videos on how to escape in these situations(http://www.fireengineering.com/topics/m/video/36928837/the-quick-release-method.htm?q=cable+entanglement) [1].

There have been documented fatalities due to cable entrapment both in the U.S. and England. In Memphis, Tennessee, in 1994, a fireman was entangled incables that had fallen after the nonmetallic raceway collapsed due to the heat (http://www.fireengineering.com/articles/print/volume-148/issue-3/features/tragedy-in-a-residential-high-rise-memphis-tennessee.html [2]).More recently in England two firemen died due in part to being tangled in cabling that had fallen from plastic raceway in the ceiling of a Southampton residential building (http://www.bbc.co.uk/news/uk-england-hampshire-22126431 [3]). An article [4] in Electrical Contracting News identifies another recent incident in which a fireman died in Stevenage, Hertfordshire, after he became entangled in electrical cables which “had fallen after plastic trunking, the only support for the cables, melted and failed.” Article [4] goes on to report that changes are in process to Great Britain’s Wiring Regulations (BS 7671 [5]) to ensure that “wiring systems in any escape route should be supported so that they are not subject to premature failure in a fire.” Revisions have already been made in a standard for fire alarm system cabling, BS 5839-1 [6], to require cable supports/raceway which will not collapse in a fire.While the documented incidents involve firefighters, it is not even known how many building occupants may have died in the past either becoming entangled in fallen cabling, overcome by smoke/heat trying to remove a cabling obstruction, or forced to seek an alternate exit due to a significant amount of cablingobstruction.

NFPA 101 (Life Safety Code, 2012) [7] already addresses the requirement to maintain egress free from obstruction. Sections 7.1.10 and 7.1.10.1 (Means ofEgress Reliability) state,7.1.10.1 General. Means of egress shall be continuously maintained free of all obstructions or impediments to full instant use in case of fire or otheremergency.Sections 12.2.5.4, 12.2.5.4.2, and 12.2.5.4.3 (New Assembly Occupancies) and 13.2.5.4, 13.2.5.4.2, and 13.2.5.4.3 (Existing Assembly Occupancies) alsoemphasize this requirement.12.2.5.4 General Requirements for Access and Egress Routes Within Assembly Areas.12.2.5.4.2 Access and egress routes shall be maintained so that any individual is able to move without undue hindrance, on personal initiative and at any time,from an occupied position to the exits.12.2.5.4.3 Access and egress routes shall be maintained so that crowd management, security, and emergency medical personnel are able to reach anyindividual at any time, without undue hindrance.13.2.5.4 General Requirements for Access and Egress Routes Within Assembly Areas.13.2.5.4.2 Access and egress routes shall be maintained so that any individual is able to move without undue hindrance, on personal initiative and at any time,from an occupied position to the exits.13.2.5.4.3 Access and egress routes shall be maintained so that crowd management, security, and emergency medical personnel are able to reach anyindividual at any time, without undue hindrance

The solution that is easy to understand and enforce is a straightforward requirement regarding the allowable materials of a cable


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support used above egress.Melting temperatures of metallic and non-metallic materials are significantly different – compare the low carbon steel melting temperature of approximately1450 °C versus 200-400 °C for many typical thermoplastics used in cable supports. This difference translates to a greater resistance to heat for steel whichenables a metallic support to survive and carry load significantly longer than nonmetallic supports. The intent is not to eliminate the use of non-metallicsupports/raceway in all applications, as they provide an appropriate and cost-effective option in other locations. The objective is to focus on egress whichcauses the highest risk to life safety.

In conclusion, there have been verifiable incidents in which firefighters have died due to entanglement from cabling fallen from plastic raceway that wasweakened due to fire. This is not just a theoretical discussion or anecdotal evidence. In addition, NFPA 101 already emphasizes the need to maintain egressfree from obstruction at all times, including during a fire. There is a clear opportunity in the NEC to improve consistency within NFPA Codes and save furtherloss of life.

Bibliography:[1] Fire Engineering Training Minutes. Presented by Mike Ciampo, Fire Department of New York. http://www.fireengineering.com/topics/m/video/36928837/the-quick-release-method.htm?q=cable+entanglement)[2] Chubb, M., and Joe Caldwell. 3/1/1995. “Tragedy in a Residential High-Rise, Memphis, Tennessee.” Fire Engineering,http://www.fireengineering.com/articles/print/volume-148/issue-3/features/tragedy-in-a-residential-high-rise-memphis-tennessee.html[3] April 15, 2013. “Shirley Towers flats blaze: ‘Possible safety breaches’”. BBC. http://www.bbc.co.uk/news/uk-england-hampshire-22126431[4] Rawlinson, J. August 2014, Vol. 34, No. 8, “Change for the Better.” Electrical Contracting News (ECN), pp. 24-25. http://edition.pagesuiteprofessional.co.uk/Launch.aspx?EID=dd8a7ebe-4f8b-4aa6-a9a1-d6b4692f6a23 (see attached)[5] BS 7671:2008+A2:2013, Requirements for electrical installations. IET Wiring Regulations. Seventeenth edition.[6] BS 5839-1:2013, Fire detection and fire alarm systems for buildings. Code of practice for design, installation, commissioning and maintenance of systemsin non-domestic premises[7] NFPA 101: Life Safety Code, 2012.





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(A) General.

Fire alarm circuits shall be installed in a neat workmanlike manner. Cables and conductors installed exposed on the surface ofceilings and sidewalls shall be supported by the building structure in such a manner that the cable will not be damaged bynormal building use. Such cables shall be supported by straps, staples, cable ties, hangers, or similar fittings designed andinstalled so as not to damage the cable. The installation shall also comply with 300.4(D).

Informational Note: Paint, plaster, cleaners, abrasives, corrosive residues, or other contaminants may result in anundetermined alteration of NPLFA and PLFA cable properties.


Mr. Tim West of Superior Cable submitted PIs dealing with painting or contaminating cables for the following mechanical execution of work sections, 725.24, 760.24, 770.24, 800.24, and 820.24.

CMP 3 resolved PI 4721 with the statement that section 110.12(B) addresses the problem as stated in the substantiation for the PI.Section 110.12 applies to equipment:

110.12 Mechanical Execution of Work. Electrical equipment shall be installed in a neat and workmanlike manner.

The definition of equipment does not include cable.

Equipment. A general term, including fittings, devices, appliances, luminaires, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation.

We agree that painting or otherwise contaminating cables can change their properties, especially the fire protection properties of plenum cables. We prefer an informational note rather than mandatory text because the mandatory text recommended in the PIs is vague and unenforceable.

The informational note recommended by this Public Comment is based on the informational notes that were adopted by FR-4552 for 820.24 and FR-4592 for 830.24.






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Submittal Date: Thu Jun 25 23:04:02 EDT 2015


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(A) Listing.

PLFA cables installed in buildings shall be listed and labeled .



Essential_Guide_to_Product_Testing_and_Certification_NOV_2014.pdf

ETL Essential Guide to Product Testing & Certification 2014/2015 North American Edition. Please review document page numbers 5, 8 and 10 to see that ETL has requirements similar to UL, that products that do not bear their certification (listed) mark are not considered by ETL as being listed.


UL recognizes the Correlating Committee created a global First Correlating Revision (FCR) which directed that in all locations where the term “and labeled” was added after “listed” during the First Revision Stage, the words “and labeled” after “listed” be deleted, returning to previous text. UL understands that the Correlating Committee appointed a task group to address several issues involving the use of the terms “listed” and “labeled,” most importantly, to clarify and establish a distinction between the terms “listed” and “labeled” which are often used interchangeably. UL supports the need for this task group. However, UL does not expect the work of this task group to affect the 2017 NEC regarding the issue of “listed and labeled.” As such, UL is submitting comments to request that the words “and labeled” be added in various locations throughout the Code for the reasons expressed in the public inputs UL submitted on this issue. UL believes that these revisions will address an ongoing problem that should not wait until the 2020 NEC for resolution.

Subsequent to the Public Input Code Panel Meetings, UL has discussed this issue with its Electrical Council whose membership includes many AHJs. The proposed revisions to the NEC received general support from the membership. This issue was also discussed at a NEMA – NRTLs Forum held on August 14, 2015 at NEMA Headquarters. UL reiterated its support for the proposed revisions. The NRTLs represented at the meeting voiced no objection to the proposals.

The rationale for the revision was simple, to provide information to the AHJ regarding the suitability of equipment they encounter. The mark on the product is the manufacturer’s attestation that the product is in compliance with the appropriate standard. NRTL’s conduct factory surveillance of products, surveillance is one method to validate the manufacturer’s attestation. Should a product be found not to be compliant the manufacturer has the option of removing the mark and shipping the product without the mark, or holding the shipment and bringing the product into compliance. In either case the “Listing” is not impacted, as the “listing” is created at the completion of the “original” certification of the product and indicates the authorization but not the mandate to label products. So the only true way an AHJ can determine whether the product he is seeing is compliant with the applicable standard is via a label on the product. Taking it one step further, listings change with time. It is quite possible that a “listing” has been withdrawn; however labeled product may still be available for sale. Should equipment that is labeled, but not listed, be deemed acceptable? Based on the NEC definitions, it is possible to have a product that meets the Article 100 definition of listed but the testing organization made the manufacture remove the label for a non-compliance issue.

As for the concerns of products that are too small to be labeled, the definition of labeled is not limited to an actual label, it also includes symbols, or other identifying marks. The Safety Standards which define the listing requirements do not address labeling of products as defined by Article 100. As a general rule, NRTL’s do not consider a product as being listed unless it is also labeled. The UL White Book states that “Only those products bearing the appropriate UL Mark and the company's name, trade name, trademark or other authorized identification should be considered as being covered by UL's Certification, Listing, Classification and Follow-Up Service. The UL Mark provides evidence of listing or labeling, which may be required by installation codes or standards.” Again the requirements for the UL Mark are not a Safety Standard requirement, they are a UL requirement and the only way to show that a product is UL Certified (Listed); other NRTL’s have similar requirements.



Public Comment No. 532-NFPA 70-2015[Definition: Labeled.]

Provides information that the label may be permitted on the container in whichon the product is packaged.

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Public Input No. 1072-NFPA 70-2014 [Definition: Labeled.]



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Submitter Full Name: JEFFREY FECTEAU

Organization: UNDERWRITERS LABORATORIES LLC

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Public Comment No. 461-NFPA 70-2015 [ Section No. 760.176 [Excluding any Sub-Sections] ]

Non–power-limited fire alarm cables installed as wiring within buildings shall be listed in accordance with 760.176(A) and (B)and as being resistant to the spread of fire in accordance with 760.176(C) through (F), and shall be marked in accordance with760.176(G). Cable used in a wet location shall be listed for use in wet locations or have a moisture-impervious metal sheath. Non–power-limited fire alarm cables shall have a temperature rating of not less than 60°C (140°F).


The panel resolution statement “The Panel maintains that 60°C is established and is a listing requirement” is quite puzzling. We agree that it is the UL listing document since we stated in the PI “Requiring a temperature rating of 60°C (140°F) is consistent with the UL listing requirements for these cables.”The temperature rating for these cables needs to be in the code. While we know it is in the UL listing, UL is not the only listing agency. Other listing agencies can choose a different temperature rating or not have one at all. The NEC is published in Spanish for use South and Central America. Can CMP 3 be sure that every country that uses the NEC has a 60°C rating?

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Public Comment No. 869-NFPA 70-2015 [ Section No. 760.176(D) ]

(D) Type NPLFR.

Type NPLFR non–power-limited fire alarm riser cable shall be listed as being suitable for use in a vertical run in a shaft or fromfloor to floor and shall also be listed as having fire-resistant characteristics capable of preventing the carrying of fire from floor tofloor. Optionally, Type NPLFR riser cables shall be permitted to be marked as Type NPLFR ST1 if they are listed as having fire-resistantcharacteristics capable of preventing the carrying of fire from floor to floor and also listed as exhibiting limited smoke characteristics.

Informational Note 1 : One method of defining fire-resistant characteristics capable of preventing the carrying of fire fromfloor to floor is that the cables pass ANSI/UL 1666-2012, Test for Flame Propagation Height of Electrical andOptical-Fiber Cables Installed Vertically in Shafts.








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Public Input No. 1721-NFPA 70-2014 [Section No. 760.176(D)]




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Public Comment No. 450-NFPA 70-2015 [ Section No. 760.179(C) ]

(C) Ratings.

The cable shall have a voltage rating of not less than 300 volts. The cable shall have a temperature rating of not less than 60°C(140°F).


PI 1609 was for 760.179(C). The title of 760.179 is Listing and Marking of PLFA Cables and Insulated Continuous Line-Type Fire Detectors. The panel resolution statement “The 60°C temperature rating is a listing requirement.” is quite puzzling. It is a listing requirement; that’s why it was proposed for the listing section, right next to the voltage rating. Cables have voltage ratings and temperature ratings; both of these listing requirements should be in the Code. Why include one, the voltage rating, and exclude the other, the temperature rating?The temperature rating for these cables needs to be in the code. While we know it is in the UL listing, UL is not the only listing agency. Other listing agencies can choose a different temperature rating or not have one at all. The NEC is published in Spanish for use South and Central America. Can CMP 3 be sure that every country that uses the NEC has a 60°C rating?

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Submittal Date: Thu Aug 27 16:36:15 EDT 2015


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Public Comment No. 870-NFPA 70-2015 [ Section No. 760.179(E) ]

(E) Type FPLR.

Type FPLR power-limited fire alarm riser cable shall be listed as being suitable for use in a vertical run in a shaft or from floor tofloor and shall also be listed as having fire-resistant characteristics capable of preventing the carrying of fire from floor to floor.Optionally, Type FPLR riser cables shall be permitted to be marked as Type FPLR ST1 if they are listed as having fire-resistantcharacteristics capable of preventing the carrying of fire from floor to floor and also listed as exhibiting limited smoke characteristics.

Informational Note 1 : One method of defining fire-resistant characteristics capable of preventing the carrying of fire fromfloor to floor is that the cables pass the requirements of ANSI/UL 1666-2012, Standard Test for Flame PropagationHeight of Electrical and Optical-Fiber Cable Installed Vertically in Shafts.








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Public Input No. 1722-NFPA 70-2014 [Section No. 760.179(E)]




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