Linear Encoders for Numerically Controlled Machine Tools

8/17/2019 Linear Encoders for Numerically Controlled Machine Tools

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September 2005

Linear Encodersfor Numerically Controlled

Machine Tools


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Further information is available on theInternet at www.heidenhain.de as well asupon request.

Product brochures:Exposed Linear EncodersAngle EncodersRotary EncodersHEIDENHAIN subsequent electronicsHEIDENHAIN controlsMeasuring Systems for Machine ToolInspection and Acceptance Testing

Technical Information brochures:Accuracy of Feed AxesSealed Linear Encoders with Single-FieldScanningEnDat 2.2 – Bidirectional Interface forPosition EncodersEncoders for Direct Drives

••••••

••

•

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This catalog supersedes all previous

editions, which thereby become invalid.The basis for ordering from HEIDENHAIN

is always the catalog edition valid when

the contract is made.

Standards (ISO, EN, etc.) apply only

where explicitly stated in the catalog.

DIADUR and AURODUR are registeredtrademarks ofDR. JOHANNES HEIDENHAIN GmbH,Traunreut.


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Overview

Linear Encoders 4

Selection Guide 6

Technical Features and Mounting Information

Measuring Principles Measuring standard 8

Absolute measuring method 8

Incremental measuring method 9

Photoelectric scanning 10

Measuring Accuracy 12

Mounting and Mechanical Design Types 14

General Mechanical Information 17

Specifications Recommended measuring Linear encoder step for positioning Series or Model

For absolute position measurement to 0.1 µm LC 400 Series 18

LC 100 Series 20

For incremental linear measurementwith very high repeatability

to 0.1 µm LF 481 22

LF 183 24

For incremental linear measurement to 0.5 µm LS 487 26

LS 187 28

For incremental linear measurementfor large measuring lengths

to 0.1 µm LB 382 – Single-Section

30

LB 382 – Multi-Section 32

Electrical Connection

Incremental Signals »1 VPP 34

Absolute Position Values EnDat 36

Fanuc and Mitsubishi 43

Connecting Elements and Cables 44

General Electrical Information 48

Evaluation Electronics 50

HEIDENHAIN Measuring Equipment 51

Content


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Linear Encoders for NC-Controlled Machine Tools

Linear encoders from HEIDENHAIN forNC-controlled machine tools can be usednearly everywhere. They are ideal formachines and other equipment whosefeed axes are in a closed loop, such asmilling machines, machining centers,boring machines, lathes and grindingmachines. The beneficial dynamic behaviorof the linear encoders, their highly reliabletraversing speed, and their acceleration inthe direction of measurement predestinethem for use on highly-dynamicconventional axes as well as on directdrives.

HEIDENHAIN also supplies linear encodersfor other applications, such as

Manual machine toolsPresses and bending machinesAutomation and production equipment

Please request further documentation,or inform yourself on the Internet atwww.heidenhain.de.

•••

Advantages of linear encodersLinear encoders measure the position oflinear axes without additional mechanicaltransfer elements. The control loop forposition control with a linear encoder alsoincludes the entire feed mechanics.Transfer errors from the mechanics can bedetected by the linear encoder on the slide,and corrected by the control electronics.This can eliminate a number of potentialerror sources:

Positioning error due to thermal behaviorof the recirculating ball screwBacklashKinematic error through ball-screw pitcherror

Linear encoders are therefore indispen-sable for machines that must fulfill highrequirements for positioning accuracyand machining speed.

•

••

Mechanical designThe linear encoders for NC-controlledmachine tools are sealed encoders: Analuminum housing protects the scale,scanning carriage and its guideway fromchips, dust, and fluids. Downward-orientedelastic lips seal the housing.

The scanning carriage travels in a low-friction guide within the scale unit. Acoupling connects the scanning carriagewith the mounting block and compensatesthe misalignment between the scale andthe machine guideways.

Depending on the encoder model, lateraland axial offsets of ± 0.2 to ± 0.3 mmbetween the scale and mounting block arepermissible.


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Scanning carriage

Mounting blockSealing lips

Photocells

DIADUR

scale

Light

source

Schematic design of the LC 183 sealed linear encoder

Thermal behavior

The combination of increasingly rapid

machining processes with completely

enclosed machines leads to ever-increasing

temperatures within the machine‘s work

envelope. Therefore, the thermal behavior

of the linear encoders used becomes

increasingly important, since it is an

essential criterion for the working accuracy

of the machine.

As a general rule, the thermal behavior of

the linear encoder should match that of the

workpiece or measured object. During

temperature changes, the linear encoder

must expand or retract in a defined,

reproducible manner. Linear encoders from

HEIDENHAIN are designed for this.

The graduation carriers of HEIDENHAIN

linear encoders have defined coefficients

of thermal expansion (see Specifications ).

This makes it possible to select the linear

encoder whose thermal behavior is best

suited to the application.

Dynamic behavior

The constant increases in efficiency and

performance of machine tools necessitate

ever-higher feed rates and accelerations,

while at the same time the high level of

machining accuracy must be maintained. In

order to transfer rapid and yet exact feed

motions, very high demands are placed on

rigid machine design as well as on the

linear encoders used.

Linear encoders from HEIDENHAIN are

characterized by their high rigidity in the

measuring direction. This is a very

important prerequisite for high-quality path

accuracies on a machine tool. In addition,

the low mass of components moved

contributes to their excellent dynamic

behavior.

Availability

The feed axes of machine tools travel quite

large distances—a typical value is 10000 km

in three years. Therefore, robust encoders

with good long-term stability are especially

important: They ensure the constant

availability of the machine.

Due to the details of their design, linear

encoders from HEIDENHAIN function

properly even after years of operation. The

contact-free principle of photoelectrically

scanning the measuring standard, as well

as the ball-bearing guidance of the

scanning carriage in the scale housing

ensure a long lifetime. This encapsulation,

the special scanning principles and, if

needed, the introduction of compressed

air, make the linear encoders very resistant

to contamination. The complete shielding

concept ensures a high degree of electrical

noise immunity.

O v e r v i e w


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Crosssection

Measuringstep

1)Accuracygrade

Measuring length

Absolute linearmeasurement

Glass scale•

To 0.1 µm ± 5 µm± 3 µm

70 mm to 1240 mmWith mounting spar or

clamping elements:

70 mm to 2040 mm

Incremental linearmeasurement with veryhigh repeatability

Steel scaleSmall signal period

••

To 0.1 µm ± 3 µm± 2 µm

50 mm to 1220 mm

Incremental linearmeasurementGlass scale•

To 0.5 µm ± 5 µm± 3 µm 70 mm to 1240 mmWith mounting spar: 70 mm to 2040 mm

Absolute linearmeasurement

Glass scale•

To 0.1 µm ± 5 µm± 3 µm

140 mm to 4240 mm

Incremental linear

measurement with veryhigh repeatability

Steel scaleSmall signal period

••

To 0.1 µm ± 3 µm

± 2 µm

140 mm to 3040 mm

Incremental linearmeasurement

Glass scale•

To 0.5 µm ± 5 µm± 3 µm

140 mm to 3040 mm

Incremental linearmeasurement for largemeasuring lengths

Steel scale tape•

To 0.1 µm ± 5 µm 440 mm to 30 040 mm

1) Recommended for position measurement2)

Available in 2006

Selection Guide

Linear encoders with slimlinescale housing

The linear encoders with slimline scalehousing are designed for limitedinstallation space. Larger measuringlengths and higher acceleration loads aremade possible by using mounting spars orclamping elements.

Linear encoders with full-sizescale housing

The linear encoders with full-size scalehousing are characterized by their sturdyconstruction, high resistance tovibration and large measuring lengths. The scanning carriage is connected with

the mounting block over an oblique bladethat permits mounting both in upright andreclining positions with the sameprotection rating.


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ScanningPrinciple

Incremental signalsSignal period

Absoluteposition

values

Model Page

Single-fieldscanning

» 1 VPP; 20 µm EnDat 2.2 LC 4832)

18

– Fanuc 02 LC 493F2)

– Mitsubishi LC 493M2)


» 1 VPP; 4 µm – LF 481 22

Single-fieldscanning » 1 VPP; 20 µm – LS 487

2)

26


» 1 VPP; 20 µm EnDat 2.2 LC 1832)

20

– Fanuc 02 LC 193F2)

– Mitsubishi LC 193M2)

Single-field

scanning

» 1 VPP; 4 µm – LF 183 24


» 1 VPP; 20 µm – LS 1872)

28


» 1 VPP; 20 µm LB 382 30

LS 487

LC 483

LF 183

LC 183

LB 382


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Measuring PrinciplesMeasuring Standard

HEIDENHAIN encoders with opticalscanning incorporate measuring standardsof periodic structures known as graduations.These graduations are applied to a carriersubstrate of glass or steel. The scalesubstrate for large measuring lengths is asteel tape.

These precision graduations aremanufactured in various photolithographicprocesses. Graduations can be fabricatedfrom:

extremely hard chromium lines on glass,matte-etched lines on gold-plated steeltape, orthree-dimensional grid structures onglass or steel substrates.

The photolithographic manufacturingprocesses developed by HEIDENHAINproduce grating periods of typically 40 µmto 4 µm.

Along with these very fine grating periods,these processes permit a high definitionand homogeneity of the line edges.Together with the photoelectric scanningmethod, this high edge definition is aprecondition for the high quality of theoutput signals.

The master graduations are manufacturedby HEIDENHAIN on custom-built high-precision ruling machines.

••

•

Absolute Measuring Method

With the absolute measuring method, the position value is available from theencoder immediately upon switch-on andcan be called at any time by thesubsequent electronics. There is no needto move the axes to find the referenceposition. The absolute position informationis read from the scale graduation, whichis formed from a serial absolute codestructure. A separate incremental track isinterpolated for the position value and atthe same time is used to generate anoptional incremental signal.

Schematic representation of an absolute code structure with anadditional incremental track (LC 483 as example)

Graduation of an absolute linear encoder


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Incremental Measuring Method

With the incremental measuring

method, the graduation consists of a

periodic grating structure. The position

information is obtained by counting the

individual increments (measuring steps)

from some point of origin. Since an

absolute reference is required to ascertain

positions, the scales or scale tapes are

provided with an additional track that bears

a reference mark. The absolute position on

the scale, established by the reference

mark, is gated with exactly one measuring

step. The reference mark must therefore

be scanned to establish an absolute

reference or to find the last selected

datum.

In some cases this may necessitate

machine movement over large lengths of

the measuring range. To speed and simplify

such „reference runs,“ many encoders

feature distance-coded reference

marks —multiple reference marks that are

individually spaced according to a

mathematical algorithm. The subsequent

electronics find the absolute reference

after traversing two successive reference

marks—only a few millimeters traverse

(see table).

Encoders with distance-coded reference

marks are identified with a ”C“ after the

model designation (e.g. LS 487C).

With distance-coded reference marks, theabsolute reference is calculated by

counting the signal periods between two

reference marks and using the following

formula:

where:

P1 = (abs B–sgn B–1) xN + (sgn B–sgn D) x abs MRR2 2

B = 2 x MRR –N

and:

P1 = Position of the first traversed

reference mark in signal periods

abs = Absolute value

sgn = Sign function (”+1“ or ”–1“)

MRR = Number of signal periods between

the traversed reference marks

N = Nominal increment between two

fixed reference marks in signalperiods (see table)

D = Direction of traverse (+1 or –1).

Traverse of scanning unit to the right

(when properly installed) equals +1.

Graduation of an incremental linear encoder

Schematic representation of an incremental graduation with

distance-coded reference marks (LS as example)

Signal period Nominal

increment N in

signal periods

Maximum

traverse

LF 4 µm 5000 20 mm

LS 20 µm 1000 20 mm

LB 40 µm 2000 80 mm

T e c h n i c a l F e a t u r e s a n d

M o u n t i n g I n f o r m a t i o n


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Photoelectric Scanning

Most HEIDENHAIN encoders operateusing the principle of photoelectricscanning. The photoelectric scanning of ameasuring standard is contact-free, andtherefore without wear. This methoddetects even very fine lines, no more thana few microns wide, and generates outputsignals with very small signal periods.

The finer the grating period of a measuringstandard is, the greater the effect ofdiffraction on photoelectric scanning.HEIDENHAIN uses two scanning principleswith linear encoders:

The imaging scanning principle forgrating periods from 20 µm and 40 µm.The interferential scanning principle for very fine graduations with gratingperiods of 8 µm and smaller.

•

•

Imaging scanning principleTo put it simply, the imaging scanningprinciple functions by means of projected-light signal generation: two scale gratingswith equal or similar grating periods aremoved relative to each other—the scaleand the scanning reticle. The carriermaterial of the scanning reticle istransparent, whereas the graduation on themeasuring standard may be applied to atransparent or reflective surface.

When parallel light passes through agrating, light and dark surfaces areprojected at a certain distance, wherethere is an index grating. When the twogratings move relative to each other, theincident light is modulated. If the gaps inthe gratings are aligned, light passesthrough. If the lines of one grating coincidewith the gaps of the other, no light passesthrough.

An array of photovoltaic cells convertsthese variations in light intensity intoelectrical signals. The specially structuredgrating of the scanning reticle filters thelight current to generate nearly sinusoidaloutput signals. The smaller the period ofthe grating structure is, the closer andmore tightly toleranced the gap must bebetween the scanning reticle and scale.

The LC, LS and LB linear encoders operateaccording to the imaging scanningprinciple.

Imaging scanning principle

LED light source

Measuring standard

Condenser lens

Scanning reticle

Photovoltaic cellarray


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Interferential scanning principleThe interferential scanning principle exploitsthe diffraction and interference of light on afine graduation to produce signals used tomeasure displacement.A step grating is used as the measuringstandard: reflective lines 0.2 µm high areapplied to a flat, reflective surface. In frontof that is the scanning reticle—a transparentphase grating with the same grating periodas the scale.

When a light wave passes through thescanning reticle, it is diffracted into threepartial waves of the orders –1, 0, and +1,with approximately equal luminousintensity. The waves are diffracted by thescale such that most of the luminousintensity is found in the reflected diffractionorders +1 and –1. These partial waves meetagain at the phase grating of the scanningreticle where they are diffracted again andinterfere. This produces essentially threewaves that leave the scanning reticle atdifferent angles. Photovoltaic cells convertthis alternating light intensity into electricalsignals.

A relative motion of the scanning reticle tothe scale causes the diffracted wave frontsto undergo a phase shift: when the gratingmoves by one period, the wave front of thefirst order is displaced by one wavelength inthe positive direction, and the wavelength ofdiffraction order –1 is displaced by onewavelength in the negative direction. Sincethe two waves interfere with each otherwhen exiting the grating, the waves areshifted relative to each other by twowavelengths. This results in two signalperiods from the relative motion of just onegrating period.

Interferential encoders function with gratingperiods of, for example, 8 µm, 4 µm andfiner. Their scanning signals are largely freeof harmonics and can be highly interpolated.These encoders are therefore especiallysuited for high resolution and high accuracy.

Sealed linear encoders that operateaccording to the interferential scanningprinciple are given the designation LF.

LEDlight source

Measuring standard

Condenser lens

Scanning reticle

Photocells

Interferential scanning principle (optics schematics)C Grating periodψ Phase shift of the light wave when passing through the

scanning reticle− Phase shift of the light wave due to motion X of the scale


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The accuracy of linear measurement ismainly determined by:

The quality of the graduationThe quality of the scanning processThe quality of the signal processingelectronicsThe error from the scanning unitguideway to the scale

A distinction is made between positionerrors over relatively large paths oftraverse—for example the entire measuringlength—and those within one signal period.

•••

•

Position error a over the measuring length ML

P o s i t i o n e r r o r

Position

Position error withinone signal period

P o s i t i o n e r r o r

Position error u within one signal period

S i g n a l l e v e l

Signal period360 °elec.

Measuring Accuracy

Position error over the measuring rangeThe accuracy of sealed linear encoders isspecified in grades, which are defined asfollows:The extreme values ±F of the measuring

curves over any max. one-meter section of

the measuring length lie within the

accuracy grade ±a. They are ascertained

during the final inspection, and are

indicated on the calibration chart.

With sealed linear encoders, these valuesapply to the complete encoder systemincluding the scanning unit. It is then

referred to as the system accuracy.

Position error within one signal periodThe position error within one signal periodis determined by the signal period of theencoder, as well as the quality of thegraduation and the scanning thereof. Atany measuring position, it does not exceed±2% of the signal period, and for the LCabsolute linear encoders it is typically ±1%.The smaller the signal period, the smallerthe position error within one signal period.

Signal period ofscanning signals

Max. position error u withinone signal period

LF ± 4 µm Approx. 0.08 µm

LC ± 20 µm Approx. 0.2 µm

LS ± 20 µm Approx. 0.4 µm

LB ± 40 µm Approx. 0.8 µm


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All HEIDENHAIN linear encoders areinspected before shipping for positioningaccuracy and proper function.

The position errors are measured bytraversing in both directions, and theaveraged curve is shown in the calibrationchart.

The Manufacturer’s Inspection Certificateconfirms the specified system accuracy ofeach encoder. The calibration standards ensure the traceability—as required byISO 9001—to recognized national orinternational standards.

For the LC, LF and LS series listed in thisbrochure, a calibration chart documentsthe position error over the measuringlength, and also states the measuring stepand measuring uncertainty of thecalibration.

Temperature rangeThe linear encoders are inspected at areference temperature of 20 °C. Thesystem accuracy given in the calibrationchart applies at this temperature.

The operating temperature range indicates the ambient temperature limitsbetween which the linear encoders willfunction properly. The storagetemperature range of –20 °C to 70 °Capplies for the device in its packaging.

Example


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Mechanical Design Types and Mounting GuidelinesLinear Encoders with Small Cross Section

The LC, LF and LS slimline linear encodersshould be fastened to a machined surfaceover their entire length, especially forhighly-dynamic requirements. Largermeasuring lengths and higher vibrationloads are made possible by using mountingspars or clamping elements (only forLC 4x3).

The encoder is mounted so that the sealinglips are directed downward or away fromsplashing water (also see GeneralMechanical Information).

Thermal behaviorBecause they are rigidly fastened usingtwo M8 screws, the linear encoders largelyadapt themselves to the mounting surface.When fastened over the mounting spar,the encoder is fixed at its midpoint to themounting surface. The flexible fasteningelements ensure reproducible thermalbehavior.The LF 481 with its graduation carrier ofsteel has the same coefficient of thermalexpansion as a mounting surface of graycast iron or steel.

MountingIt is surprisingly simple to mount thesealed linear encoders from HEIDENHAIN:You need only align the scale unit at severalpoints along the machine guideway. Stopsurfaces or stop pins can also be used toalign the scale. Use the mounting gauge toset the gap between the scale unit and thescanning unit easily and exactly. Ensurethat the lateral tolerances are alsomaintained.

Accessories: Mounting gaugeId. Nr. 528753-01

Mounting with clamping elementsThe scale housing of the LC 4x3 isfastened at both ends. In addition, it canalso be attached to the mounting surfaceat every 400 mm by clamping elements.This makes it very easy to fasten thehousing at the center of the measuringlength (recommended for highly-dynamicapplications with measuring lengthsgreater than 640 mm). This also eliminatesthe need of a mounting spar for measuring

lengths greater than 1240 mm.

Accessories: Clamping elementsId. Nr. 556975-xx

Shipping brace


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Installation with mounting sparThe use of a mounting spar can be of greatbenefit when mounting slimline linearencoders. They can be fastened as part ofthe machine assembly process, so thatlater the encoder can be easily clamped asa final step. Easy exchange also facilitatesservicing.

The universal mounting spar wasdeveloped specifically for the LC 4x3 andthe LS 4x7 with single-field scanning

1). It

offers the following advantages:

Rapid mountingThe components necessary for clampingare premounted. This simplifiesmounting, saves time and improves thereliability.

Freely selectable cable exitThe LC 4x3 and the LS 4x7 with single-field scanning

1) can be mounted with

either side facing the universal mountingspar. This permits the cable exit to belocated on the left or right—a veryimportant feature if installation space islimited.

Mechanically compatible versionsBoth the universal mounting spar andthe LC 4x3 and the LS 4x7 with single-field scanning

1) are absolutely

compatible mechanically to the previousversions. Any combinations are possible,such as the LS 4x6 with the universalmounting spar, or the LC 4x3 with theprevious mounting spar.

Of course only the combination of theLC 4x3 or the LS 4x7 with single-fieldscanning1) und the universal mounting sparpermit selection of mounting with thecable exit at left or right.

The universal mounting spar must beordered separately, even for measuringlengths over 1240 mm.

1) Id. Nr. 56052x-xx; available in 2006

•

•

•

Mounting spar


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Linear Encoders with Large Cross Section

Shipping brace

The LB, LC, LF and LS full-size linearencoders are fastened over their entirelength onto a machined surface. This givesthem a high vibration rating.The inclined arrangement of the sealinglips permits universal mounting withvertical or horizontal scale housing withequally high protection rating.

Thermal behaviorThe thermal behavior of the LB, LC, LF andLS 100 linear encoders with large crosssection has been optimized.

On the LF the steel scale is cemented to asteel carrier that is fastened directly to themachine element.

On the LB the steel scale tape is clampeddirectly onto the machine element. The LBtherefore takes part in all thermal changesof the mounting surface.

The LC and LS are fixed to the mountingsurface at their midpoint. The flexiblefastening elements permit reproduciblethermal behavior.

MountingWhen mounting sealed linear encodersfrom HEIDENHAIN, the shipping bracealready sets the proper gap between thescale unit and the scanning unit. You needonly align the scale unit at several pointsalong the machine guideway. Stop surfacesor stop pins can also be used for this.

Mounting the multi-section LB 382The LB 382 with measuring lengths over3240 mm is mounted on the machine inindividual sections:

Mount and align the individual housingsectionsPull in the scale tape over the entirelength and tension itPull in the sealing lipsInsert the scanning unit

Adjustment of the tensioning of the scaletape enables linear machine errorcompensation up to ± 100 µm/m.

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General Mechanical Information

MountingTo simplify cable routing, the mountingblock of the scanning unit is usuallyscrewed onto a stationary machine part.The mounting location for the linearencoders should be carefully considered inorder to ensure both optimum accuracyand the longest possible service life.

The encoder should be mounted asclosely as possible to the working planeto keep the Abbe error low.To function properly, linear encodersmust not be continuously subjected tostrong vibration; the more solid parts ofthe machine tool provide the bestmounting surface in this respect.Encoders should not be mounted onhollow parts or with adapters. Amounting spar is recommended for thesealed linear encoders with small crosssection.The linear encoders should be mountedaway from sources of heat to avoidtemperature influences.

AccelerationLinear encoders are subject to varioustypes of acceleration during operation andmounting.

The indicated maximum values forvibration apply for frequencies of 55 to2000 Hz (IEC 60068-2-6). Anyacceleration exceeding permissiblevalues, for example due to resonancedepending on the application andmounting, might damage the encoder.Comprehensive tests of the entiresystem are required.The maximum permissible accelerationvalues (semi-sinusoidal shock) for shockand impact are valid for 11 ms(IEC 60068-2-27).Under no circum-stances should a hammer or similarimplement be used to adjust or positionthe encoder.

Required moving forceThe required moving force is the maximumforce required to move the scale unitrelative to the scanning unit.

Expendable partsIn particular the following parts in encodersfrom HEIDENHAIN are subject to wear:

LED light sourceBearingsSealing lips

•

•

•

•

•

•••

ProtectionSealed linear encoders fulfill the require-ments for IP 53 protection according toIEC 60529, provided that they are mountedwith the sealing lips facing away fromsplash water. If necessary, provide aseparate protective cover. If the encoder isexposed to particularly heavy concentrationsof coolant and mist, compressed air can beconducted into the scale housing to provide IP 64 protection to more effectively preventthe ingress of contamination. The LB, LC,LF and LS sealed linear encoders fromHEIDENHAIN are therefore equippedwith inlets at both end pieces and on themounting block of the scanning unit.

The compressed air introduced directly ontothe encoders must be cleaned by a micro-filter and must comply with the followingquality classes as per ISO 8573-1:

Solid contaminant: Class 1(max. particle size 0.1 µm and max.particle density 0.1 mg/m

3 at 1 · 10

5 Pa)

Total oil content: Class 1(max. oil concentration 0.01 mg/m

3 at

1 · 105 Pa)Maximum pressure dew point: Class 4(+3 °C at 2 · 105 Pa)

•

•

•

The required air flow is 7 to 10 l/min perlinear encoder; permissible pressure is inthe range of 0.6 to 1 bar (9 to 14 psi). Thecompressed air flows through connectingpieces with integrated throttle (includedwith LB, LC, LF, LS 1x6, and LS 4x6 linearencoders).

HEIDENHAIN offers the DA 300Compressed Air Unit for purifying andconditioning compressed air. It consists oftwo filter stages (fine filter and activatedcarbon filter), automatic condensation trap,and a pressure regulator with pressuregauge. It also includes 25 meters ofpressure tubing as well as T-joints andconnecting pieces for four encoders.The DA 300 can supply air for up to 10encoders with a maximum total measuringlength of 35 meters.

At an operating pressure of 7 bars, thecompressed air conducted to the encoderby far exceeds the required purity. Itspressure gauge and automatic pressureswitch (available as accessories) effectivelymonitor the DA 300.

DA 300Compressed Air Unit


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LC 400 SeriesAbsolute linear encoders for measuring steps to 0.1 µm (resolution to 0.005 µm)High positioning accuracy and traversing speed through single-field scanningFor limited installation space

• • •

Dimensions in mm

Ô

Õ

Ô = Without mounting sparÕ = With mounting sparF = Machine guidewayP = Gauging points for alignmentk = Required mating dimensionsd = Compressed air inlets = Beginning of measuring length (ML) (at 20 mm) = Direction of scanning unit motion for output

signals in accordance with interfacedescription

Mounting spar

ML m

70 ... 520 0

570 ... 920 1

1020 ... 1340 2

1440 ... 1740 3

1840 ... 2040 4


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LC 483 with mounting spar

Specifications LC 4831)

LC 493F1)

LC 493M1)

Measuring standardExpansion coefficient

DIADUR glass scale with absolute track and incremental track

Þtherm approx. 8 x 10 –6

K –1

, with mounting spar: Þtherm approx. 9 x 10 –6

K –1

Accuracy grade* ± 3 µm, ± 5 µm

Measuring length ML* in mm Mounting spar* or clamping elements* optional

70 120 170 220 270 320 370 420 470 520 570 620 720 770820 920 1020 1140 1240

Only with mounting spar* or clamping elements*1340 1440 1540 1640 1740 1840 2040

Absolute position values EnDat 2.2 Serial interface Fanuc 02 Mitsubishi high-speed serialinterface

Resolution

Accuracy ± 3 µm

Accuracy ± 5 µm

0.005 µm

0.01 µm

0.01 µm

0.05 µm

Calculation time tcal

EnDat 2.1 command set EnDat 2.2 command set

< 1 ms† 5 µs

– –

Incremental signals » 1 VPP2)

–

Grating period/signal period 20 µm –

Cutoff frequency –3dB ‡ 150 kHz –

Power supply without load 3.6 to 5.25 V/< 300 mA

Electrical connection Separate adapter cable (1 m/3 m/6 m/9 m) connectable to mounting block

Cable length3)

† 150 m; depending on the

interface and subsequentelectronics

†30 m †20 m

Traversing speed † 180 m/min

Required moving force † 5 N

Vibration 55 to 2000 Hz

Shock 11 msAcceleration

Without mounting spar: † 100 m/s2 (IEC 60068-2-6)

With mounting spar and cable exit right/left: † 200 m/s2 /100 m/s

2 (IEC 60068-2-6)

† 300 m/s2 (IEC 60068-2-27)

† 100 m/s2 in measuring direction

Operating temperature 0 to 50 °C

Protection IEC 60529 IP 53 when installed according to mounting instructionsIP 64 with use of compressed air from DA 300

Weight Encoder: 0.2 kg + 0.5 kg/m measuring length, mounting spar: 0.9 kg/m

* Please select when ordering1)

Available in 2006. Specifications preliminary.2)

Depends on adapter cable3)

With HEIDENHAIN cable

LC 483 without mounting spar

S p e c

i fi c a t i o n s


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Specifications LF 481


DIADUR phase grating on steelÞtherm approx. 10 x 10

–6 K

–1, with mounting spar: Þtherm ca. 9 x 10

–6 K

–1


Measuring length ML* in mm Mounting spar* recommended

50 100 150 200 250 300 350 400 450 500 550 600 650 700750 800 900 1000 1120 1220

Incremental signals »1 VPP

Grating periodSignal period

8 µm4 µm

Reference marks* LF 481

LF 481C

ML 50 mm: 1 reference mark at midpointML 100 to 1000 mm: 2, located 25 mm from the beginning and end of the measuring lengthFrom ML 1120 mm: 2, located 35 mm from the beginning and end of the measuring lengthDistance-coded

Cutoff frequency –3dB ‡ 200 kHz

Power supplywithout load

5 V ± 5 %/< 200 mA


Cable length1) † 150 m



Vibration 55 to 2000 HzShock 11 ms

Acceleration

† 80 m/s2 (IEC 60068-2-6)† 100 m/s2 (IEC 60068-2-27)

† 30 m/s2 in measuring direction



Weight without mounting spar 0.4 kg + 0.5 kg/m measuring length



LF 481 without mounting spar

LF 481 with mounting spar


24/52


25/5225

Specifications LF 183


DIADUR phase grating on steelÞtherm approx. 10 x 10

–6 K

–1


Measuring length ML* in mm 140 240 340 440 540 640 740 840 940 1040 1140 1240 1340 1440

1540 1640 1740 1840 2040 2240 2440 2640 2840 3040

Incremental signals »1 VPP

Grating periodSignal period

8 µm4 µm

Reference marks* LF 183

LF 183C

Selectable with magnets every 50 mmStandard setting: 1 reference mark in the centerDistance-coded


Power supply

without load

5 V ± 5 %/< 200 mA





Vibration 55 to 2000 HzShock 11 msAcceleration

† 150 m/s2 (IEC 60068-2-6)† 300 m/s2 (IEC 60068-2-27)† 100 m/s2 in measuring direction



Weight 1.1 kg + 3.8 kg/m measuring length




26/52


27/5227

LS 487 without mounting spar

LS 487 with mounting spar

Specifications LS 4871)


Glass scale with DIADUR graduationÞtherm approx. 8 x 10

–6 K

–1, with mounting spar: Þtherm approx. 9 x 10

–6 K

–1


Measuring length ML* in mm Mounting spar* recommended

70 120 170 220 270 320 370 420 470 520 570 620 720 770820 920 1020 1140 1240

Only with mounting spar*1340 1440 1540 1640 1740 1840 2040

Reference marks* LS 487

LS 487C

Selectable with magnets every 50 mm;Standard: ML 70 mm: 1 in the center; up to ML 1020 mm: 2, each 35 mm from beginning/end of ML;from ML 1140mm: 2, each 45 mm from beginning/end of MLDistance-coded

Incremental signals » 1 VPP

Grating period/signal period 20 µm



5 V ± 5 %/< 120 mA





Vibration 55 to 2000 Hz

Shock 11 msAcceleration

Without mounting spar: † 100 m/s2 (IEC 60068-2-6)With mounting spar and cable exit right/left: † 200 m/s2 /100 m/s2 (IEC 60068-2-6)† 300 m/s2 (IEC 60068-2-27)† 100 m/s2 in measuring direction





Id. Nr. 56052x-xx. Available in 2006. Specifications preliminary.

2) With HEIDENHAIN cable


28/5228

LS 187Incremental linear encoder for measuring steps to 0.5 µmDefined thermal behaviorHigh vibration ratingHorizontal mounting possibleWith single-field scanning

• • • • •

Dimensions in mm

Ô,Õ,Ö = Mounting optionsF = Machine guidewayP = Gauging points for alignmentk = Required mating dimensionsd = Compressed air inletr = Reference mark position on LS 1xxc = Reference mark position on LS 1xxCs = Beginning of measuring length (ML)

= Direction of scanning unit motion for output signals in accordance with interface description


29/5229

Specifications LS 1871)


Glass scale with DIADUR graduationÞtherm approx. 8 x 10

–6 K

–1


Measuring length ML* in mm 140 240 340 440 540 640 740 840 940 1040 1140 1240 1340 1440

1540 1640 1740 1840 2040 2240 2440 2640 2840 3040

Reference marks* LS 187 LS 187C

Selectable with magnets every 50 mm, standard setting: 1 reference mark in the centerDistance-coded





5 V ± 5 %/< 120 mA











Available in 2006. Specifications preliminary.2)



30/52


31/5231

Specifications LB 382 up to ML 3040 mm


Stainless steel tape with AURODUR graduationÞtherm approx. 10 x 10

–6 K

–1

Accuracy grade* ± 5 µm

Measuring length ML* in mm Single-section housing

440 640 840 1040 1240 1440 1640 1840 2040 2240 2440 2640 2840 3040

Reference marks* LB 382 LB 382C

Selectable with selector plates every 50 mm, standard setting: 1 reference mark in the centerDistance-coded





5 V ± 5 %/< 150 mA



Traversing speed † 120 m/min (180 m/min on request)










32/52


33/5233

Specifications LB 382 from ML 3240 mm


Stainless steel tape with AURODUR graduationSame as machine main casting

Accuracy grade* ± 5 µm

Measuring length ML* Kit with single-section AURODUR steel tape and housing sections for measuring lengths

from 3240 mm to 30040 mm in 200 mm steps.Housing section lengths: 1000 mm, 1200 mm, 1400 mm, 1600 mm, 1800 mm, 2000 mm

Reference marks* LB 382 LB 382C

Selectable with selector plates every 50 mmDistance-coded





5 V ± 5 %/< 150 mA













34/5234

InterfacesIncremental Signals » 1 VPP

HEIDENHAIN encoders with » 1 VPP interface provide voltage signals that canbe highly interpolated.

The sinusoidal incremental signals Aand B are phase-shifted by 90° elec. andhave an amplitude of typically 1 VPP. Theillustrated sequence of output signals—with B lagging A—applies for the directionof motion shown in the dimensiondrawing.

The reference mark signal R has a usablecomponent G of approx. 0.5 V. Next to thereference mark, the output signal can bereduced by up to 1.7 V to a quiescent valueH . This must not cause the subsequentelectronics to overdrive. Even at thelowered signal level, signal peaks with theamplitude G can also appear.

The data on signal amplitude apply whenthe power supply given in the specificationsis connected to the encoder. They refer to adifferential measurement at the 120 ohmterminating resistor between the associatedoutputs. The signal amplitude decreaseswith increasing frequency. The cutofffrequency indicates the scanning frequencyat which a certain percentage of the originalsignal amplitude is maintained:

–3 dB cutoff frequency:70 % of the signal amplitude –6 dB cutoff frequency:50 % of the signal amplitude

Interpolation/resolution/measuring stepThe output signals of the 1 VPP interfaceare usually interpolated in the subsequentelectronics in order to attain sufficientlyhigh resolutions. For velocity control, interpolation factors are commonly over1000 in order to receive usable velocityinformation even at low speeds.

Measuring steps for position measure-ment are recommended in the specifi-cations. For special applications, otherresolutions are also possible.

Short-circuit stabilityA temporary short circuit of one output to0 V or 5 V does not cause encoder failure,but it is not a permissible operatingcondition.

Short circuit at 20 °C 125 °C

One output < 3 min < 1 min

All outputs < 20 s < 5 s

•

•

Interface Sinusoidal voltage signals » 1 VPP

Incremental signals 2 sinusoidal signals A and BSignal level M: 0.6 to 1.2 VPP; typically 1 VPPAsymmetry |P – N|/2M: † 0.065Amplitude ratio MA /MB: 0.8 to 1.25Phase angle |ϕ1 + ϕ2|/2: 90° ± 10° elec.

Reference marksignal

1 or more signal peaks RUsable component G: 0.2 to 0.85 VQuiescent value H: 0.04 V to 1.7 VSwitching threshold E, F: ‡ 40 mVZero crossovers K, L: 180° ± 90° elec.

Connecting cable

Cable lengthsPropagation time

HEIDENHAIN cable with shieldingPUR [4(2 x 0.14 mm

2) + (4 x 0.5 mm

2)]

Max. 150 m distributed capacitance 90 pF/m6 ns/m

Any limited tolerances in the encoders are listed in the specifications.

Signal period360° elec.

Rated value

A, B, R measured with oscilloscope in differential mode

Cutoff frequencyTypical signalamplitude curve withrespect to thescanning frequency

S i g n a l a m p l i t u d e [ % ]

Scanning frequency [kHz] –3dB cutoff frequency –6dB cutoff frequency


35/5235

Input circuitry of the subsequent

electronics

Dimensioning

Operational amplifier MC 34074

Z0 = 120−

R1 = 10 k− and C1 = 100 pF

R2 = 34.8 k− and C2 = 10 pF

UB = ±15 V

U1 approx. U0

–3dB cutoff frequency of circuitry

Approx. 450 kHz

Approx. 50 kHz with C1 = 1000 pF

and C2 = 82 pF

The circuit variant for 50 kHz does reduce

the bandwidth of the circuit, but in doingso it improves its noise immunity.

Circuit output signals

Ua = 3.48 VPP typical

Gain 3.48

Signal monitoring

A threshold sensitivity of 250 mVPP is to be

provided for monitoring the 1 VPP

incremental signals.

Incremental signals

Reference mark

signal

Ra < 100−, typ. 24−Ca < 50 pF

ΣIa < 1 mAU0 = 2.5 V ± 0.5 V

(relative to 0 V of thepower supply)

Encoder Subsequent electronics

Pin layout

12-pin coupling M23 12-pin connector M23 15-pin D-sub connector

for IK 115/IK 215 or on encoder

Power supply Incremental signals Other signals

12 2 10 11 5 6 8 1 3 4 9 7 /

4 12 2 10 1 9 3 11 14 7 5/8/13/15 14 /

UP SensorUP0 V Sensor0 V A+ A– B+ B– R+ R– Vacant Vacant Vacant

Brown/

Green

Blue White/

Green

White Brown Green Gray Pink Red Black / Violet Yellow

Shield on housing; UP = power supply voltage

Sensor: The sensor line is connected internally with the corresponding power line

E l e c t r i c a l C o n n e c t i o n


36/52


37/5237

Benefits of the EnDat InterfaceAutomatic self-configuration: Allinformation required by the subsequentelectronics is already stored in theencoderHigh system security through alarmsand messages for monitoring anddiagnosisHigh transmission reliability throughcyclic redundancy checkingFaster configuration during installation:Datum shifting through offsetting by avalue in the encoder

Other benefits of EnDat 2.2A single interface for all absolute andincremental encodersAdditional information (limit switch,temperature, acceleration)Quality improvement: Position valuecalculation in the encoder permitsshorter sampling intervals (25 µs)

Advantages of purely serial transmissionspecifically for EnDat 2.2 encoders

Simple subsequent electronics withEnDat receiver chipSimple connection technology: Standard connecting element (M12;8-pin), single-shielded standard cableand few wiresMinimized transmission times throughadaptation of the data word length to theresolution of the encoderHigh clock frequencies up to 8 MHz.Position values available in thesubsequent electronics after onlyapprox. 10 µsSupport for state-of-the-art machinedesigns e.g. direct drive technology

•

•

•

•

•

•

•

•

•

•

•

•

FunctionsThe EnDat interface transmits absoluteposition values or additional physicalquantities (only EnDat 2.2) in an unambig-uous time sequence and serves to readfrom and write to the encoder‘s internalmemory. Some functions are available onlywith EnDat 2.2 mode commands.

Position values can be transmitted with orwithout additional information. The additionalinformation types are selectable via theMemory Range Select (MRS) code. Otherfunctions such as parameter reading andwriting can also be called after the memoryarea and address have been selected.Through simultaneous transmission withthe position value, additional information canalso be requested of axes in the feedbackloop, and functions executed with them.

Parameter reading and writing is possibleboth as a separate function and in connec-tion with the position value. Parameterscan be read or written after the memoryarea and address is selected.

Reset functions serve to reset the encoderin case of malfunction. Reset is possibleinstead of or during position valuetransmission.

Servicing diagnosis makes it possible toinspect the position value even at standstill.A test command has the encoder transmitthe required test values.

You can find more information in theTechnical Information for EnDat 2.2 document or on the Internet atwww.endat.de.

VersionsThe extended EnDat interface version 2.2 is

compatible in its communication, commandset and time conditions with version 2.1,but also offers significant advantages. Itmakes it possible, for example, to transferadditional information with the positionvalue without sending a separate requestfor it. The interface protocol was expandedand the time conditions (clock frequency,processing time, recovery time) wereoptimized. In addition, encoders withordering designations EnDat 02 or EnDat 22have an extended power supply range.

Both EnDat 2.1 and EnDat 2.2 are available

in versions with or without incrementalsignals. EnDat 2.2 encoders feature a highinternal resolution. Therefore, depending onthe control technology being used,interrogation of the incremental signals isnot necessary. To increase the resolution ofEnDat 2.1 encoders, the incremental signalsare evaluated in the subsequent electronics.

Command setThe command set is the sum of allavailable mode commands. The EnDat 2.2command set includes EnDat 2.1 modecommands. When a mode command from

the EnDat 2.2 command set is transmittedto EnDat-01 subsequent electronics, theencoder or the subsequent electronicsmay generate an error message.

EnDat with command set 2.2 (includesEnDat 2.1 command set)

Position values for incremental andabsolute encodersAdditional information on position value- Diagnostics and test values- Absolute position values after referencerun of incremental encoders

- Parameter upload/download

- Commutation- Acceleration- Limit position signal- Temperature of the encoder PCB- Temperature evaluation of an externaltemperature sensor (e.g. in the motorwinding)

EnDat with command set 2.1Absolute position valuesParameter upload/downloadResetTest command and test values

•

•

••••

Interface Commandset

Orderingdesignation

Version Clockfrequency

EnDat EnDat 2.1 orEnDat 2.2

EnDat 01 With incremental signals † 2 MHz

EnDat 21 Without incremental signals

EnDat 2.2 EnDat 02 With incremental signals † 2 MHz

EnDat 2.2 EnDat 22 Without incremental signals † 8 MHz


38/5238

Selecting the transmission typeTransmitted data are identified as either

position values, position values withadditional information, or parameters. Thetype of information to be transmitted isselected by mode commands. Modecommands define the content of thetransmitted information. Every modecommand consists of three bits. To ensurereliable transmission, every bit is transmittedredundantly (inverted or double). If theencoder detects an erroneous modetransmission, it transmits an error message.The EnDat 2.2 interface can also transferparameter values in the additionalinformation together with the position value.

This makes the current position valuesconstantly available for the control loop,even during a parameter request.

Control cycles for transfer of positionvaluesThe transmission cycle begins with thefirst falling clock edge. The measuredvalues are saved and the position valuecalculated. After two clock pulses (2T), toselect the type of transmission thesubsequent electronics transmit the modecommand ”Encoder transmit positionvalue“ (with/without additional information).

After successful calculation of the absoluteposition value (t cal – see Specifications ), thestart bit initiates the data transmission fromthe encoder to the subsequent electronics.The subsequent error messages, error 1and error 2 (only with EnDat 2.2commands), are group signals for allmonitored functions and serve as failuremonitors.

Beginning with the LSB, the encoder thentransmits the absolute position value as acomplete data word. Its length depends on

the encoder being used. The number ofrequired clock pulses for transmission of aposition value is saved in the parameters ofthe encoder manufacturer. The data trans-mission of the position value is completedwith the Cyclic Redundancy Check (CRC).

In EnDat 2.2, this is followed by additionalinformation 1 and 2, each also concludedwith a CRC. With the end of the data word,the clock must be set to HIGH. After 10 to30 µs or 1.25 to 3.75 µs (with EnDat 2.2parameterizable recovery time tm) the dataline falls back to LOW. Then a new data

transmission can begin by starting theclock.

Without delaycompensation

With delaycompensation

Clock frequency fc 100 kHz ... 2 MHz 100 kHz ... 8 MHz

Calculation time forPosition value

Parameterstcaltac

See Specifications Max. 12 ms

Recovery time tm EnDat 2.1: 10 to 30 µsEnDat 2.2: 10 to 30 µs or 1.25 to 3.75 µs (fc ‡ 1 MHz)(parameterizable)

tR Max. 500 ns

tST – 2 to 10 µs

Data delay time tD (0.2 + 0.01 x cable length in m) µs

Pulse width tHIGH

tLOW

0.2 to 10 µs

0.2 to 50 ms/30 µs (with LC)

Pulse width fluctuationHIGH to LOW max. 10%

Mode commands

Encoder transmit position value

Selection of the memory areaEncoder receive parametersEncoder transmit parametersEncoder receive reset

1)

Encoder transmit test valuesEncoder receive test commands

•

••••••

E n D a t 2 . 1

E n D a t 2 . 2

Encoder transmit position value with additional informationEncoder transmit position value and receive selection of memory area

2)

Encoder transmit position value and receive parameters2)

Encoder transmit position value and transmit parameters2)

Encoder transmit position value and receive error reset2)

Encoder transmit position value and receive test command2)

Encoder receive communication command3)

•••••••

1) Same reaction as switching the power supply off and on

2) Selected additional information is also transmitted3)

Reserved for encoders that do not support the safety system

The time absolute linear encoders needfor calculating the position values t cal differs depending on whether EnDat 2.1or EnDat 2.2 mode commands aretransmitted (see the Specifications ). If

the incremental signals are evaluated foraxis control, then the EnDat 2.1 modecommands should be used. Only in thismanner can an active error message betransmitted synchronously to the currentlyrequested position value. EnDat 2.1 modecommands should not be used for pureserial position-value transfer for axiscontrol.


39/52


40/5240

EnDat 2.1 – Transfer of PositionValues

EnDat 2.1 can transmit position valuesselectably with interrupted clock pulse (asin EnDat 2.2) or continuous clock pulse.

Interrupted clockThe interrupted clock is intended particularlyfor time-clocked systems such as closedcontrol loops. At the end of the data wordthe clock signal is set to HIGH level. After 10to 30 µs (tm), the data line falls back to LOW.Then a new data transmission can begin bystarting the clock.

Continuous clock

For applications that require fast acquisitionof the measured value, the EnDat interfacecan have the clock run continuously.Immediately after the last CRC bit hasbeen sent, the data line is switched tohigh for one clock cycle, and then to low.The new position value is saved with thevery next falling edge of the clock and isoutput in synchronism with the clock signalimmediately after the start bit and alarmbit. Because the mode command Encodertransmit position value is needed onlybefore the first data transmission, thecontinuous-clock transfer mode reduces

the length of the clock-pulse group by9 periods per position value.

Synchronization of the seriallytransmitted code value with theincremental signalAbsolute encoders with EnDat interfacecan exactly synchronize serially transmittedabsolute position values with incrementalvalues. With the first falling edge (latchsignal) of the CLOCK signal from thesubsequent electronics, the scanningsignals of the individual tracks in theencoder and counter are frozen, as are also

the A/D converters for subdividing thesinusoidal incremental signals in thesubsequent electronics.

The code value transmitted over the serialinterface unambiguously identifies oneincremental signal period. The positionvalue is absolute within one sinusoidalperiod of the incremental signal. Thesubdivided incremental signal cantherefore be appended in the subsequentelectronics to the serially transmitted codevalue.

Encoder Subsequent electronics

Latch signal

Subdivision

Counter C o m p a r a t o r

Parallelinterface

1 VPP

1 VPP

After power on and initial transmission ofposition values, two redundant positionvalues are available in the subsequentelectronics. Since encoders with EnDatinterface guarantee a precise synchro-nization—regardless of cable length—ofthe serially transmitted absolute value with

Position value CRCCRC

Save new positionvalue

Save new positionvalue

n = 0 to 7; depending on system Continuous clock

the incremental signals, the two valuescan be compared in the subsequentelectronics. This monitoring is possibleeven at high shaft speeds thanks to theEnDat interface’s short transmission timesof less than 50 µs. This capability is aprerequisite for modern machine designand safety systems.

Encoder savesposition value

Subsequent electronics

transmit mode command

Mode command Position valueCyclic RedundancyCheck

Interrupted clock


41/5241

Parameters and Memory AreasThe encoder provides several memory

areas for parameters. These can be readfrom by the subsequent electronics, andsome can be written to by the encodermanufacturer, the OEM, or even the enduser. Certain memory areas can be write-protected.

The parameters, which in most casesare set by the OEM, largely define thefunction of the encoder and the EnDat

interface. When the encoder is exchanged,it is therefore essential that its parametersettings are correct. Attempts to configuremachines without including OEM data can

result in malfunctions. If there is any doubtas to the correct parameter settings, theOEM should be consulted.

Parameters of the encoder manufacturerThis write-protected memory area containsall information specific to the encoder, such as encoder type (linear/angular,singleturn/multiturn, etc.), signal periods,position values per revolution, transmissionformat of position values, direction ofrotation, maximum speed, accuracydependent on shaft speeds, support ofwarnings and alarms, part number and

serial number. This information forms thebasis for automatic configuration. Aseparate memory area contains theparameters typical for EnDat 2.2: Status ofadditional information, temperature,acceleration, support of diagnostic anderror messages, etc.

Absolute encoder Subsequentelectronics

Absoluteposition value

Operatingparameters

Operatingstatus

Parametersof the OEM

Parameters of the encodermanufacturer for

EnDat 2.1 EnDat 2.2

E n D a t i n t e r f a c e

Monitoring and DiagnosticFunctions

The EnDat interface enables comprehen-sive monitoring of the encoder withoutrequiring an additional transmission line.The alarms and warnings supported bythe respective encoder are saved in the“parameters of the encoder manufacturer“memory area.

DiagnosisCyclic information on encoder function andadditional diagnostic values are transmittedin the additional information.

Error message

An error message becomes active if amalfunction of the encoder might resultin incorrect position values. The exactcause of the disturbance is saved in the“operating status” memory and can beinterrogated in detail. Errors include, forexample,

Light unit failureSignal amplitude too lowError in calculation of position valuePower supply too high/lowCurrent consumption is excessive

Here the EnDat interface transmits the

error bits, error 1 and error 2 (only withEnDat 2.2 commands). These are groupsignals for all monitored functions andserve for failure monitoring. The two errormessages are generated independentlyfrom each other.

WarningThis collective bit is transmitted in thestatus data of the additional information.It indicates that certain tolerance limitsof the encoder have been reached orexceeded—such as shaft speed or thelimit of light source intensity compensation

through voltage regulation—withoutimplying that the measured positionvalues are incorrect. This function makesit possible to issue preventive warnings inorder to minimize idle time.

Cyclic Redundancy CheckTo ensure reliability of data transfer, acyclic redundancy check (CRC) is per-formed through the logical processingof the individual bit values of a data word.This 5-bit long CRC concludes everytransmission. The CRC is decoded in thereceiver electronics and compared with the

data word. This largely eliminates errorscaused by disturbances during datatransfer.

•••••

Incrementalsignals *)

*) Depends onencoder

» 1 VPP A*)

» 1 VPP B*)

Parameters of the OEMIn this freely definable memory area, theOEM can store his information, e.g. the“electronic ID label” of the motor in whichthe encoder is integrated, indicating themotor model, maximum current rating, etc.

Operating parametersThis area is available for a datum shift andthe configuration of diagnostics. It can beprotected against overwriting.

Operating statusThis memory area provides detailedalarms or warnings for diagnosticpurposes. Here it is also possible toactivate write protection for the OEMparameter and operating parametermemory areas, and to interrogate theirstatus. Once write protection is activated,it cannot be removed.

Safety SystemThe safety system is in preparation. Safety-oriented controls are the planned applicationfor encoders with EnDat 2.2 interface. Referto IEC 61800 standard Adjustable speedelectrical power drive systems Part 5-2.


42/5242

Pin Layout for

17-pincoupling M23

Power supply Incremental signals Absolute position values

7 1 10 4 11 15 16 12 13 14 17 8 9

UP SensorUP

0 V Sensor0 V

Insideshield

A+ A– B+ B– DATA DATA CLOCK CLOCK

Brown/ Green

Blue White/ Green

White / Green/ Black

Yellow/ Black

Blue/ Black

Red/ Black

Gray Pink Violet Yellow

Shield on housing; UP = Power supply voltage

Sensor: The sensor line is connected internally with the corresponding power lineVacant pins or wires must not be used!

15-pinD-sub connector (male)

for IK 115/IK 215

15-pinD-sub connector (female)

for HEIDENHAIN controlsand IK 220

Power supply Incremental signals1)

Absolute position values

4 12 2 10 6 1 9 3 11 5 13 8 15

1 9 2 11 13 3 4 6 7 5 8 14 15

UP SensorUP

0 V Sensor0 V

Insideshield

A+ A– B+ B– DATA DATA CLOCK CLOCK

Brown/

Green

Blue White/

Green

White / Green/

Black

Yellow/

Black

Blue/

Black

Red/

Black

Gray Pink Violet Yellow

Shield on housing; UP = power supply voltageSensor: The sensor line is connected internally with the corresponding power lineVacant pins or wires must not be used!1) Not assigned for adapter cable Id. Nr. 524599-xx for IK 115/IK215

8-pincoupling M12

Power supply Absolute position values

2 8 1 5 3 4 7 6

UP1)

UP 0 V1)

0 V DATA DATA CLOCK CLOCK

Blue Brown/Green White White/Green Gray Pink Violet Yellow

Shield on housing; UP = power supply voltage1)

For power lines configured in parallelVacant pins or wires must not be used!


43/52


44/5244

The pins on connectors are numbered inthe direction opposite to those oncouplings or flange sockets, regardless ofwhether the connecting elements are

Male contacts or

Female contacts

When engaged, the connections provide

protection to IP 67 (D-sub connector: IP 50;IEC 60529). When not engaged, there is noprotection.

Accessories for flange socket and M23mounted couplings

Bell sealId. Nr. 266526-01

Threaded metal dust capId. Nr. 219926-01

Connecting Elements and CablesGeneral Information

Connector insulated: Connectingelement with coupling ring, available

with male or female contacts.

Symbols

Coupling insulated:Connecting element with external thread;

Available with male or female contacts.

Symbols

D-sub connector: For HEIDENHAINcontrols, counters and IK absolute valuecards.

Symbols

Flange socket: Permanently mountedon the encoder or a housing, withexternal thread (like the coupling), andavailable with male or female contacts.

Symbols

M23

M23

M23

M23

Mounted coupling

with central fastening

Mounted couplingwith flange

x: 41.7 y: 15.2

Cutout for mounting M23

M12

M12


45/5245

Adapter Cables

For incremental linear encoders Cable ¬ LB 382LF 183

LF 481 LS 187LS 487

Adapter cablewith M23 coupling (male)

6 mm 310128-xx 310123-xx 360645-xx

Adapter cablewithout connector

6 mm 310131-xx 310134-xx 354319-xx

Adapter cablewith M23 connector (male)

6 mm4.5 mm

310127-xx –

310122-xx –

344228-xx352611-xx

Adapter cable in metal armorwith M23 connector (male)

10 mm 310126-xx 310121-xx 344451-xx

Adapter cable

with D-sub connector (15-pin)

6 mm 298429-xx 298430-xx 360974-xx

For absolute linear encoders – Fanuc/Mitsubishi Cable ¬ LC 193FLC 493F

LC 193MLC 493M


6 mm4.5 mm

–545547-xx

Adapter cablewith Fanuc connector

6 mm4.5 mm

–547300-xx

– –

Available cable lengths: 1 m/3 m/6 m/9 m

For absolute linear encoders – EnDat Cable ¬ LC 183LS 483with incremental signals

LC 183LS 483without incremental signals

Adapter cable

with M23 coupling (male)

6 mm 533631-xx –

Adapter cable in metal armorwith M23 coupling (male)

10 mm 558362-xx –

Adapter cablewith D-sub connector

6 mm 558717-xx –


4.5 mm – 533661-xx

Adapter cable in metal armorwith M12 coupling (male)

10 mm – 550678-xx

M12

M12


46/5246

Connecting Cables 12-pin » 1 VPP 17-pin EnDat/Fanuc/Mitsubishi

PUR connecting cable ¬ 8 mmfor encoders with coupling or flange socket

PUR connecting cable ¬ 8 mmfor encoders with connector

Complete with M23 connector(female) and M23 connector (male)

12-pin 298399-xx Complete with M23 coupling (female)and M23 connector (male)

12-pin 298400-xx

Complete with M23 connector(female) and M23 coupling (male)

17-pin 323897-xx With one M23 coupling (female) 12-pin 298402-xx

Complete with M23 connector(female) and D-sub connector (female)for HEIDENHAIN controls and IK 220

12-pin 310199-xx17-pin 332115-xx

Complete with M23 connector(female) and D-sub connector (male)for IK 115/IK 215

17-pin 324544-xx

With one M23 connector (female) 12-pin 309777-xx17-pin 309778-xx

Cable without connectors 12-pin 244957-01 [4(2 x 0.14 mm2) + (4 x 0.5 mm

2)]

17-pin 266306-01 [(4 x 0.14 mm2) + 4(2 x 0.14 mm2) + (4 x 0.5 mm2)]

Connecting cable for EnDat 2.2 encoders without incremental signals with M12 connecting element

Completewith M12 connector (female), 8-pin,and M12 connector (male), 8-pin

368330-xx Completewith M12 connector (female) and D-subconnector (male) for IK 115/IK 215

524599-xx

PUR adapter cable for Fanuc interface, dia. 8 mm PUR adapter cable for Mitsubishi interface,dia. 8 mm

Complete

with M23 connector (female), 17-pin,and Fanuc connector[(2 x 2 x 0.14 mm

2) + (4 x 1 mm

2)]

534855-xx Complete

with M23 connector (female), 17-pin,and Mitsubishi connector[(2 x 2 x 0.14 mm

2) + (4 x 0.5 mm

2)]

344625-xx

Cable without connectors[(2 x 2 x 0.14 mm

2) + (4 x 1 mm

2)]

354608-01 Cable without connectors[(2 x 2 x 0.14 mm

2) + (4 x 1 mm

2)]

354608-01

M12 M12 M12


47/5247

Connecting Elements 12-pin » 1 VPP 17-pin EnDat

M23 connectors and couplings

Coupling on encoder cable M23 coupling (male) Mating element to coupling onencoder cable or flange socket M23 connector (female)

For cable ¬ 4.5 mm ¬ 6 mm

12-pin 291698-1412-pin 291698-0317-pin 291698-26

For connecting cable, diameter 8 mm 12-pin 291697-0517-pin 291697-26

Connector on encoder cable M23 connector (male) Mating element on connectingcable for encoder connector

M23 coupling (female)

For cable ¬ 4.5 mm ¬ 6 mm 12-pin 291697-0612-pin 291697-07 For connecting cable, diameter 8 mm 12-pin 291698-02

Connector for connection tosubsequent electronics

M23 connector (male)

For connecting cable, diameter 8 mm 12-pin 291697-0817-pin 291697-27

Couplings and M23 flange socket for mounting

M23 flange socket

(female)

M23 coupling on

mounting base withflange (male)

12-pin 315892-0817-pin 315892-10

For cable ¬ 6 mm ¬ 8 mm

12-pin 291698-0812-pin 291698-3117-pin 291698-29

M23 coupling onmounting base withcentral fastening (male)

M23 coupling onmounting base withflange (female)

For cable ¬ 6 mm 12-pin 291698-3317-pin 291698-37

For cable ¬ 6 mm ¬ 8 mm

12-pin 291698-1712-pin 291698-0717-pin 291698-35

Adapter connector » 1 VPP/» 11 µAPP

For converting the 1-VPP output signals to 11-µAPPinput signals for the subsequent electronics;M23 connector (female, 12-pin) and M23 connector (male, 9-pin)

364914-01


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Reliable Signal Transmission

Electromagnetic compatibility/CE complianceWhen properly installed, HEIDENHAINencoders fulfill the requirements forelectromagnetic compatibility according to89/336/EEC with respect to the genericstandards for:

Noise immunity IEC 61000-6-2:Specifically:

– ESD IEC 61000-4-2 – Electromagnetic fields IEC 61000-4-3 – Burst IEC 61000-4-4 – Surge IEC 61000-4-5 – Conducted disturbances IEC 61000-4-6 – Power frequency magnetic fields IEC 61000-4-8 – Pulse magnetic fields IEC 61000-4-9

Interference IEC 61000-6-4:Specifically: – For industrial, scientific and

medical (ISM) equipment IEC 55011 – For information technology equipment IEC 55022

Transmission of measuring signals—electrical noise immunityNoise voltages arise mainly throughcapacitive or inductive transfer. Electricalnoise can be introduced into the systemover signal lines and input or outputterminals.Possible sources of noise are:

Strong magnetic fields fromtransformers and electric motorsRelays, contactors and solenoid valvesHigh-frequency equipment, pulsedevices, and stray magnetic fields fromswitch-mode power suppliesAC power lines and supply lines to theabove devices

IsolationThe encoder housings are isolated againstall circuits.Rated surge voltage: 500 V(preferred value as per VDE 0110 Part 1)

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Protection against electrical noiseThe following measures must be taken toensure disturbance-free operation:

Use only original HEIDENHAIN cables.Watch for voltage attenuation on thesupply lines.Use connectors or terminal boxes withmetal housings. Do not conduct anyextraneous signals.Connect the housings of the encoder,connector, terminal box and evaluationelectronics through the shield of thecable. Connect the shielding in the areaof the cable inlets to be as induction-freeas possible (short, full-surface contact).Connect the entire shielding system withthe protective ground.Prevent contact of loose connectorhousings with other metal surfaces.The cable shielding has the functionof an equipotential bonding conductor.If compensating currents are to beexpected within the entire system,a separate equipotential bondingconductor must be provided.Also see EN 50178/4.98 Chapter 5.2.9.5regarding “protective connection lineswith small cross section.”Connect HEIDENHAIN position encodersonly to subsequent electronics whosepower supply is generated through doubleor strengthened insulation against linevoltage circuits. Also see IEC 364-4-41: 1992, modified Chapter 411 regarding“protection against both direct andindirect touch” (PELV or SELV).

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Do not lay signal cables in the directvicinity of interference sources (inductiveconsumers such as contacts, motors,frequency inverters, solenoids, etc.).Sufficient decoupling from interference-signal-conducting cables can usually beachieved by an air clearance of 100 mm(4 in.) or, when cables are in metal ducts,by a grounded partition.A minimum spacing of 200 mm (8 in.) toinductors in switch-mode power suppliesis required. Also see EN 50178 /4.98Chapter 5.3.1.1 regarding cables andlines, and EN 50174-2 /09.01, Chapter 6.7regarding grounding and potentialcompensation.When using multiturn encoders inelectromagnetic fields greater than30 mT, HEIDENHAIN recommendsconsulting with the main facility inTraunreut.

Both the cable shielding and the metalhousings of encoders and subsequentelectronics have a shielding function. Thehousings must have the same potentialand be connected to the main signal groundover the machine chassis or by means of aseparate potential compensating line.Potential compensating lines should have aminimum cross section of 6 mm

2 (Cu).

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Minimum distance from sources of interference


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IBV seriesInterpolation and digitizing electronicsInterpolation and digitizing electronicsinterpolate and digitize the sinusoidaloutput signals (» 1 VPP) fromHEIDENHAIN encoders up to 100-fold, andconvert them to TTL square-wave pulsesequences.

For more information, see the Interpolationand Digitizing Electronics brochure forIBV 660 as well as the IBV 100/EXE 100 product overview.

IBV 101 IBV 102 IBV 660

Input signals » 1 VPP

Encoder inputs Flange socket, 12-pin female

Interpolation (adjustable) 5-fold10-fold

25-fold 50-fold100-fold

25-fold 50-fold100-fold200-fold400-fold

Minimum edge separation Adjustable from 2 to 0.125 µs,depending on input frequency

Adjustable from0.8 to 0.1 µs,depending oninput frequency

Output signals 2 TTL square-wave pulse trains Ua1 and Ua2 and theirinverted signals and £Reference pulse Ua0 and ¤Interference signal ¥

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Power supply 5 V ± 5%

IBV 101

IK 220Universal PC Counter CardThe IK 220 is an expansion board for AT-compatible PCs for recording the measuredvalues of two incremental or absolutelinear or angle encoders. The subdivisionand counting electronics subdivide thesinusoidal input signals up to 4096-fold. A driver software package is included indelivery.

For more information, see the IK 220Product Information sheet.

IK 220

Input signals(switchable)

» 1 VPP » 11 µAPP EnDat 2.1 SSI

Encoder inputs Two D-sub connectors (15-pin), male

Max. input frequency 500 kHz 33 kHz –

Max. cable length 60 m 10 m

Signal subdivision(signal period : meas. step) Up to 4096-fold

Data register for measuredvalues (per channel)

48 bits (44 bits used)

Internal memory For 8192 position values

Interface PCI bus (plug and play)

Driver software anddemonstration program

For WINDOWS 98/NT/2000/XPIn VISUAL C++, VISUAL BASIC and BORLAND DELPHI

Dimensions Approx. 190 mm × 100 mm

Evaluation Electronics


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KR HEIDENHAIN LTD. Suite 1415, Family Tower Building 958-2 Yeongtong-Dong

Paldal-Gu, Suwon 442-470 Kyeonggi-Do, South Korea

{ (82) 312011511 e-mail: [email protected]

MX HEIDENHAIN CORPORATION MEXICO Av. Las Américas 1808 Fracc. Valle Dorado 20235, Aguascalientes, Ags., Mexico

{ (449) 9130870 e-mail: i

Linear Encoders for Numerically Controlled Machine Tools

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