The Motor Protection Consultants This presentation is for the exclusive use of Sprecher + Schuh employees, authorized distributors, and manufacturer’s.

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Slide 2 The Motor Protection Consultants Slide 3 This presentation is for the exclusive use of Sprecher + Schuh employees, authorized distributors, and manufacturers representatives. No other use is authorized without written consent from: Sprecher + Schuh 15910 International Plaza Drive Houston, TX 77032-2439 (281) 847-2000 Copyright 1996 Author Slide 4 3 A Guide to Applying According to NEC and UL Motor Circuit Controllers U L Tested Slide 5 4 Direct Access Menu You may jump directly to the desired section by selecting from the menu below NEC 430-52Individual BCPDs NEC 430-52Individual BCPDs NEC 430-152BCPD Selection Table NEC 430-152BCPD Selection Table NEC 240-6Next Size Larger BCPD NEC 240-6Next Size Larger BCPD NEC 430-53AGroups 1HP or less NEC 430-53AGroups 1HP or less NEC 430-53BSmall Motor Groups NEC 430-53BSmall Motor Groups NEC 430-53COther Group Installations NEC 430-53COther Group Installations NEC 430-52C6Type E Motor Controllers NEC 430-52C6Type E Motor Controllers Group ExamplesGroup BCPD Sizing Group ExamplesGroup BCPD Sizing NEC 430-53DMotor Tap Rules NEC 430-53DMotor Tap Rules Application DataAdditional Reference Menu Application DataAdditional Reference Menu Start from the Top NEC 100Definitions NEC 100Definitions Slide 6 5 Words in White Italics are taken directly from the NEC Words in captions are interpretations of the NEC In the Following Slides Slide 7 6 Click on this book to return to the Direct Access Menu Slide 8 7 NEC Article 100 - Definitions M Branch Circuit The circuit conductors between the final short-circuit device (protecting the circuit) and the motor load. Slide 9 8 M Disconnect A device designed to apply main power or disconnect main power from a branch circuit. An At Motor must be within sight and within 50 feet of the motor to provide the maintenance electrician a degree of safety. NEC Article 100 - Definitions Slide 10 9 BCPD Fused Device or Circuit Breaker M Branch-Circuit short-circuit & ground-fault Protection Device Slide 11 10 Disconnect & BCPD A single device can incorporate the function of Disconnect and BCPD but this is NOT a code requirement. NEC Article 100 - Definitions Fused Device or Circuit Breaker M Slide 12 11 M Controller A device or group of devices that serves to govern, in some predetermined manner, the electric power delivered to the connected load. NEC Article 100 - Definitions Slide 13 12 NEC 430-52 Selecting an Individual Motor Circuit BCPD Slide 14 13 NEC 430-52 Selecting an Individual Motor Circuit BCPD (a) General The motor branch-circuit short-circuit and ground-fault protection device shall comply with (b) and either (c) or (d), as applicable. (b) All Motors The motor branch-circuit short-circuit and ground-fault protection device shall be capable of carrying the starting current of the motor. (c )Rating or Setting (17) 1- A protective device having a rating or setting not exceeding the value calculated according to the value given in Table 430-52 shall be used. Slide 15 14 NEC 430-52 Selecting an Individual Motor Circuit BCPD The BCPD for a motor must be selected according to Table 430-52 Slide 16 15 NEC Table 430-52 Maximum Rating or Setting of Motor Branch-Circuit Short-Circuit and Ground-Fault Protective Devices Slide 17 16 NEC 430-52 C.1 Exception No. 1 Where the values for branch-circuit short-circuit and ground-fault protective devices determined by Table 430- 152 do not correspond to the standard sizes or ratings of fuses, nonadjustable circuit breakers, thermal protective devices, or possible settings of adjustable circuit breakers, any of which are adequate to carry the load, the next higher size, rating, or setting shall be permitted., Slide 18 17 NEC 240-6 Standard BCPD Sizes The next standard size BCPD is allowed if the calculation does not match a standard size per NEC 240-6. Continue NEC 240-6 Slide 19 18 NEC 430-52 Individual BCPDs M M M M Example: Four Starter Power Circuit Distribution Switch BCPDs (i.e., fuses) Contactors Overloads Motors Slide 20 19 NEC 430-52 Individual BCPD May be one of the following: A non-time delay fuse A time delay fuse An inverse-time circuit breaker (thermal-magnetic breaker) A magnetic-only circuit breaker (MCP or HMCP) Slide 21 20 NEC 430-52 C NEC 430-52 C contains seven options. Option #1 was to select the BCPD from the Table 430-52. Options 2-5 covers applications that do not normally apply to Motor Circuit Controllers which are explained by the reference below & summarized on the next slide. Summary Option 2-5 Slide 22 21 C) OTHER GROUP INSTALLATIONS 1 - Select a BCPD from the Table 430-52 consisting of fuses or circuit-breaker 2- The OLR max. amp rating of the up-stream BCPD should not be exceeded 3- MCPs should only be used as BCPDs in a UL Listed Combination starter 4- BCPDs selected for multi-speed motors must protect the smallest HP winding 5- I 2 t Fuses can be used with a solid state controllers if a label is placed in the panel NEC 430-52 C Individual BCPD Option 1-7 6- 7- Slide 23 22 NEC 430-52 (C- Option 6 ) Selecting an Individual Motor Circuit BCPD Option 6 is new to the 1999 NEC and the key is to understand what a Self-protected combination controller is and how this relates to UL 508 Type E approval. (Click reference button below for details) Summary Option 6 Slide 24 23 (4) Functions of a Combination Starter National Electric Code Slide 25 24 C) OTHER GROUP INSTALLATIONS 1 - Select a BCPD from the Table 430-152 consisting of fuses or circuit-breaker 2- The OLR max. amp rating of the up-stream BCPD should not be exceeded 3- MCPs should only be used as BCPDs in a UL Listed Combination starter 4- BCPDs selected for multi-speed motors must protect the smallest HP winding 5- I 2 t Fuses can be used with a solid state controllers if a label is placed in the panel 6- UL Listed Type E Self-protected combination controller can be a BCPD NEC 430-52 C Individual BCPD Option 1-7 7- Slide 26 25 NEC 430-52 C NEC 430-52 C-Option #7 is also new in the 1999 NEC and covers a special application for motor circuit controllers which are explained by the reference below & summarized on the next slide. Summary Option 7 Slide 27 26 C) OTHER GROUP INSTALLATIONS 1 - Select a BCPD from the Table 430-152 consisting of fuses or circuit-breaker 2- The OLR max. amp rating of the up-stream BCPD should not be exceeded 3- MCPs should only be used as BCPDs in a UL Listed Combination starter 4- BCPDs selected for multi-speed motors must protect the smallest HP winding 5- I 2 t Fuses can be used with a solid state controllers if a label is placed in the panel 6- UL Listed Type E Self-protected combination controller can be a BCPD NEC 430-52 C Individual BCPD Option 1-7 7- A short-circuit only protector can be used as a BCPD if the assembly including the OLR is UL Listed as a combination Slide 28 27 Individual BCPD NEC 430-52 & the corresponding sections of UL508 provides for seven options in the use of a BCPD to protect an individual branch circuit and a single motor. There may be multiple BCPDs in a control panel. Slide 29 28 NEC 430-52 requires individual BCPDs to protect every motor circuit NEC 430-53 allows for a single BCPD to protect multiple motor circuits in a group installation NEC 430-52 vs. NEC 430-53 Slide 30 29 NEC 430-53 Group Installation Outline Several motors or loads on 1 branch circuit A)Not over 1HP or B)If smallest motor is protected or C)Other group installations Slide 31 30 NEC 430-53 A Several motors or loads on 1 branch circuit A)Not over 1HP or B)If smallest motor is protected or C)Other group installations Summary 430-53A Slide 32 31 A single BCPD not exceeding 20 Amps for 120 Volt 1-phase or 15 Amps for any circuit 208-575 Volt (1-phase or 3-phase) may protect multiple motors if: (1) 1800 RPM motors have an FLA < 6 Amps. (2) The BCPD rating does not exceed the maximum rating shown on the overload relay label. (3) UL approved overload relays comply with 430-32. NEC 430-53 A Not Over 1HP Slide 33 32 NEC 430-53 A M M M M Group BCPD 120V, 20A Max. 3-Phase V, 15A Max. Individual BCPDs NOT are NOT required Contactor BCPD rating may not be exceeded Motors 1HP, 6 FLA Max. each Slide 34 33 NEC 430-53 B Several motors or loads on 1 branch circuit A)Not over 1HP or B)If smallest motor is protected or C)Other group installations Summary 430-53B Slide 35 34 A single BCPD may protect multiple motors and other loads if all the following conditions are met: NEC 430-53 B If the Smallest Motor Protected (1)BCPD shall not exceed that allowed by 430-152 to protect the smallest motor. (2)BCPD will not open under the inrush current of starting and will carry the combined FLA of motors and/or other load(s). Slide 36 35 3HP 2HP Individual BCPDs are NOT required Group BCPD 15A Max. Example #3: Contactors Overloads Motors NEC 430-53 B If the Smallest Motor Protected Slide 37 36 Several motors or loads on 1 branch circuit NEC 430-53 A or B A)Group fusing is widely used under this provision. or B)This provision is limited to 2 or 3 motors < 5 HP and simultaneous starting may not be allowable. Slide 38 37 Several motors or loads on 1 branch circuit A)Not over 1HP or B)If smallest motor is protected or C)Other group installations NEC 430-53 C Summary 430-53C Slide 39 38 C) OTHER GROUP INSTALLATIONS (1) Factory assembled multi-starter panel - with the BCPD installed or - separate BCPD and labeled panel or (2) Field installed separate assemblies and (3) All of the following conditions are met: 1- OLR must be group rated 2- Controller must be group rated 3- Circuit breakers must be thermal-magnetic type 4- BCPD must be sized properly 5- KAIC rating should be coordinated NEC 430-53 C A Summary C) Other Group Installations Slide 40 39 NEC 430-53 C Examples A few examples might help to clarify the selection process for a Group Installation B.C.P.D. Continue Slide 41 40 This section of the NEC has caused some controversy due to its vagueness. The reference button below will support our interpretation. NEC 430-53 D Single Motor Taps NEC 430-53D Summary Slide 42 41 NEC 430-53 D part 3 This means most 25 ampere frame motor circuit controller that only allows for #10 wire maximum might be as large as 400 amperes. Slide 43 42 NEC 430-53 D part 3 Single Motor Taps Slide 44 43 Application of Mini-CBs Mini-CBs There are a lot of products with over lapping approvals and in many cases confusion about applicable standards resulting in mis-application of the products and non-compliance with UL and NEC requirements. A salesman told me we could use Mini-CBs and save money!? Continue Slide 45 44 Single large motor grouped with small motors Single contactor controlling a group of motors Continue Select for Additional Reference NEC 430-87 UL 508 Group OLRs Location in Control Circuit Group OLR Group Rated OLRs Are Not BCPDs OLRs are not BCPD Slide 46 45 Slide 47 46 Slide 48 47 Slide 49 48 Slide 50 49 Slide 51 50 Slide 52 Slide 53 52 Slide 54 The Motor Protection Consultants