ACU-RITE ENC 125 T/E User Manual

ENC 125 T/E

REFERENCE MANUAL

Acu-Rite Companies Inc.

ENC 125 T/E Table of Contents

Page

Introduction............................................................................ 2

Mounting Preparation ........................................................... 3

Mounting Information ........................................................... 4

Encoder Dimensions - ENC 125 T (top mount) ................... 5

Encoder Dimensions - ENC 125 E (end mount) .................. 6

Mounting Requirements........................................................ 7

Typical Mounting (s) .............................................................. 8

Encoder Installation Procedure ............................................ 9

Checking your Installation....................................................12

Electrical Shielding.............................................................. 13

Troubleshooting ................................................................... 14

Mechanical Specifications ................................................... 15

Output Signals and Pin-Outs.............................................. 16

Electrical Specifications ...................................................... 17

The Acu-Rite Companies Inc.Warranty ............................. 18

Brackets ...

Leveling

Blocks

Reading head

mounting
brackets

Available in right or

left (shown) hand

6” Vertical side

bracket

8” Vertical side

bracket

4” Extension

bracket

Page

• Installation brackets and kits are available.

• Your authorized distributor can assist you in selecting
brackets for your installation.

1 Acu-Rite Companies Inc.

Introduction / Supplied Items ENC 125 T/E

The ENC 125 T and E Precision Glass Scale Linear Encoders
provides the accuracy and reliability of an Acu-Rite
Companies Inc. measuring system.
Features include:

• Resolutions of 5µm and 10µm.

• Accuracy Grade of ± 10µm/1000mm.

• Reference signals on 100mm intervals.

• Braided cables: 42”

< encoders - 13 ft. length.

42”> encoders - 19 ft. length.

• Two scale case forms:

- ENC 125 T: Top mount scale; 2” - 120” measuring length

- ENC 125 E: End mount scale; 2” - 22” measuring length

• Mounting fasteners provided with scale.

• Mounting brackets available.

Shipping carton contents

A

For future ordering information or warranty service, record
the linear encoder catalog number located on the scale
assembly tag, and the serial number from the reading head
tag.

Catalog No. Serial No.
Axis # 1: _______________ __________________
Axis # 2: _______________ __________________
Axis # 3: _______________ __________________
Axis # 4: _______________ __________________

Date of purchase: ____________________________________

Distributor: ____________________________________
Address: ____________________________________
Telephone: ____________________________________

B

A • ENC 125 T or E linear encoder
B • Reference Manual
C • Encoder and Cable mounting hardware

Acu-Rite Companies Inc. 2

C

ENC 125 T/E Mounting Preparation

Please follow these preparation guide lines.

ENC 125 T

• Understand your mounting requirements.

• Mount with lip seals down and away from the work area.

• Brackets should be kept as short and rigid as possible.

• Surfaces must be in good condition, clean, and free of dirt.
Remove paint from machined surfaces used for mounting.

• Alignment brackets must not be removed until

2.0

[50.8]

ENC 125 E

“L” = Measuring length

+ 1.75” nominal

over travel

2.0

[50.8]

instructed.

• Never mount with lip seals upward or towards work area.

2.4

[61]

“L” = Measuring length

+ 1.75” nominal

over travel

2.4

[61]

• Machine travel can not exceed the encoder measuring length.

• Either limit machine travel or use correct length scale.

Cable direction

Plug

Cover plate

Cable grommet

T-10 Torx screw (2)

• Determine the cable exit direction before installing the encoder.

• To change the cable exit direction; remove the cover plate and
rotate the cable 180°.

3 Acu-Rite Companies Inc.

Mounting Information ENC 125 T/E

Use this information to plan your Linear Encoder
installation.

• Mount the linear encoders close to machine guide ways to
ensure system accuracy.

• If space between the reading head and the mounting
surface exceeds .18”, use a mounting bracket or spacer to
reduce space.

• Acu-Rite Companies Inc. bracket kit instructions provide
step by step installation procedures.

Alignment bracket removal clearance

(ENC 125 E end mounting scale case shown for reference)

Alignment

bracket

1.0

[25mm]

1.38

[35mm]

Alignment

bracket

Move bracket past

the cable strain relief

• Clearance requirements for alignment bracket removal.

• Alignment brackets must not be removed until

instructed.

Tolerances ...

.010

//

X

-A- = Axis travel

.010

//

• Tolerances of .010” TIR apply to all mounting dimensions.

• Top mounted form X= 2.37”.

• End mounted form X= 1.90”.

Offset
mounting

Axis parting

line

.005 - .180”

Max. Gap

ENC 125 T

Axis parting

Underside of end

caps to be flush
with the parting

line

line

ENC 125 E

.005 - .180”

Max. Gap

• Use reading head leveling set screws.

• Reading head bracket required for a space >.18”.

A

A

Acu-Rite Companies Inc. 4

ENC 125 T/E Encoder Dimensions

ENC 125 T

(top mounted scale case)

2.0

[50.8]

1.72 [43.7]

(or M4) SHCS

.37 [9.4]

1.125 [28.6]

Ø For 8-32

mounting

screw

Measuring length + 5.75

[146]

15.75

[400] Typ.

1.25 [32]

Min. bend rad.

2.25

[57.1]

.56 [14.2]

15.75

[400] Typ.

Mounting holes

for 10-32 SHCS

.12 [3]

2.0 [50.8]

.28 [7.1]

.95 [24.1]

2.37

[60.2]

.71

[18]

.31 [7.9]

.57 [14.5]

.070 [1.7]

5 Acu-Rite Companies Inc.

Encoder Dimensions ENC 125 T/E

ENC 125 E

(end mounted scale case)

.56

[14.2]

.94 [24]

.37 [9.4]

Ø For 8-32

(or M4) SHCS

mounting

screw

1.125

[28.6]

Measuring length + 6.55 [166.4]

Measuring length + 5.437 [138.1]

Mounting hole

Ø .500 C’bore Ø .313 Thru

1.25 [32]

Min. bend rad.

.56 [14.2]

2.250
[57.1]

.12
[3]

.56 [14.2]

.95

[24.1]

1.90

[48.3]

.71 [18]

.31 [7.9]

.57 [14.5]

.070 [1.7]

Acu-Rite Companies Inc. 6

ENC 125 T/E Mounting Requirements

Mounting options can be adapted to machine mounting

ENC 125 E

M6 Flat washer x .017” thk. (2)

surfaces using spacers, standoffs, leveling set screws. A
spar can be used for the ENC 125 E encoder.

• Measuring length and mechanical configuration of your

Mounting hole cover (2)

machine determine your options.

• Fastener lengths described on this page are included with
the encoder or the backup spar.

M3 x 8mm SHSS (3)

• Mounting can be direct to the machine surface or with the
aid of leveling blocks, spacers or back up spar.

ENC 125 T

Backup spar mounting
for ENC 125 E encoder

M5 Flat washer

10-32 x 1-1/4” SHCS

M3 x 8mm SHSS (3)

• Mounting can be direct to the machine surface or with the

8-32 x 1” SHCS (2)

1/4-20 x 1/2” BHCS

& M6 Flat washer

aid of leveling blocks or spacers. • For use with ENC 125 E scale case only.

1/4-20 x 1/2” BHCS (2)

8-32 x 1” SHCS (2)

M4 x 8mm SHSS

7 Acu-Rite Companies Inc.

Typical Mounting (s) ENC 125 T/E

A variety of mounting conditions can be accommodated.

• The machine configuration determines the brackets and
encoder style required for installation.

• Typical mounting conditions are shown; flush with reading

Flush mounting surfaces ENC 125 T

Mounting

surfaces

flush

head bracket, and ENC 125 E encoder with backup spar.

• The 8-32 SHCS for mounting the reading head is a
standard low head style fastener.

8-32 x 5/8” SHCS

(trim if necessary)

Reading head bracket required

• Flush mounting surfaces, reading head bracket required.

• Bracket used to reduce head to mounting surface offset.

• Use reading head leveling screws for alignment.

Flush mounting surfaces ENC 125 E

Mounting

surfaces

flush

8-32 x 5/8” SHCS

(trim if necessary)

Reading head bracket required

• Flush mounting surfaces, reading head bracket required.

• Bracket used to reduce head to mounting surface offset.

• Use reading head leveling screws for alignment.

Acu-Rite Companies Inc. 8

Backup spar & bracket

8-32 x 5/8” SHCS

(trim if necessary)

Reading head bracket required

Mounting

surfaces

offset

• Offset mounting surfaces with a backup spar.

• Bracket used to reduce head to mounting surface gap.

• Use reading head leveling set screws for alignment.

ENC 125 T/E Encoder Installation Procedure

These steps apply to typical encoder mounting conditions and
assumes the mounting surface is parallel to the machine
travel to within .010”.

• Acu-Rite Companies Inc. bracket kit instructions supercede
this section.

• Adjust drill depths and fastener lengths as required.

• Contact your authorized Distributor should you require
additional assistance.

Scale case

Alignment brackets (2)

C

L

Reading head assembly

Cable assembly

• Move the reading head to the center of the scale case by
sliding the reading head and brackets along the case.

Center mounting axis

-A- = Axis travel

Axis parting line

Align top of scale case to

within .015” of -A-

Scale case

End mounting hole (typical)

• Move the machine axis to its center of travel and mark the
axis for future reference.

• Locate the encoder so that a suitable mounting position is
provided for both the scale case and the reading head.
Keep the underside of end caps approximately flush with
the underside of the table (or axis parting line).

• Mark the location of one end mounting hole to the
mounting surface and remove encoder.

-A- = Axis travel

-A-

Align to within .010” TIR to -A-

10-32 x1-1/4” SHCS & M5 flat washer

Drill / tap

for 10-32

• Drill & tap the first end mounting hole location.

• Attach the encoder and align to within .010” TIR. to -A-.

• Transfer punch the remaining mounting holes and remove
the encoder.

9 Acu-Rite Companies Inc.

Encoder Installation Procedure ENC 125 T/E

-A- = Axis travel

-A-

Align to within .010” TIR to -A-

10-32 x 1-1/4” SHCS & M5 flat washer

• Drill / tap the remaining mounting holes.

• Attach the encoder and align the face and the top of the scale case
to within .010” TIR. to -A- (refer to page 4, “Tolerances”).

• Secure the encoder in place maintaining this alignment.

C

L

Reading head mounting holes

• Return the table to the center of travel. Move the reading
head to the center of the scale case.

• Transfer punch the two reading head mounting holes. If
using a reading head bracket, use the next step.

• Slide the reading head to one side, and drill and tap the
hole locations for an 8-32 x 1/2” deep.

Acu-Rite Companies Inc. 10

Reading head bracket

• Attach the bracket to the reading head with the 8-32 x 5/8”
BHCS.

• Transfer punch the two reading head bracket mounting
holes to the machine.

• Remove the bracket, drill and tap the hole locations for an
1/4-20 x 1/2” deep. Attach the bracket to the machine with
(2) 1/4-20 x .5” BHCS and washers.

Gap

8-32 x 5/8” SHCS

(M4 x 20mm)

Do not tighten prior to adjusting leveling set screws

• Insert, but do not tighten 8-32 (M4) reading head screws.

• A gap will exist between the reading head and the
bracket.

ENC 125 T/E Encoder Installation Procedure

Connecting

Secure excess

cable

Provide slack

loops

Leveling screw (3)

• Place a .001”-.003” shim between the leveling set screws
and mounting surface.

• Adjust each set screw until a slight drag is felt on the shim.

• Evenly tighten the 8-32 (M4) reading head mounting

screws.

• Route the cables with slack loops to allow for axis motion.

• Secure excess cable by fastening with clips or ties.

Attach connector

• Attach the linear encoder connectors to the readout.

Alignment bracket
removal

Slide brackets away from reading head and cable.

Twist 45°

• Slide the brackets away from the reading head.

• Remove the alignment brackets and save for future use.

11 Acu-Rite Companies Inc.

Checking the Installation ENC 125 T/E

These steps will confirm proper operation of your installation.
The counting Test confirms proper electrical operation. The

Repeatability
Test

Repeatability Test checks the installation integrity
Counting Test:

• Configure the readout’s encoder and display resolution (see
manual).

• Move the axis and compare the display to the movement.

Repeatability Test:

• Locate an indicator on one end of the encoder and zero the
readout and indicator.

• Move the axis through the full travel and return to dial zero.

• Readout should read zero ± 1 count.

• Zero the display and indicator.

• Move axis to the end of it’s travel return to dial zero.

Place dial indicator at the end of the moving
component (scale assembly or reading head).

• Readout should read zero ± 1 count.

Counting Test

Readout

• Move the axis and compare the display to the movement.

Acu-Rite Companies Inc. 12

ENC 125 T/E Electrical Shielding

Connect a ground wire from the terminal on the back of the
readout to the machine or earth ground. Attach a ground wire
from the machine to a solid earth ground.

With the encoder attached to the machine and the cable
connected to the readout, check shielding by measuring
resistance between connector housing and scale unit.

Desired value: 1 W max.

ENC 125 E

shown

13 Acu-Rite Companies Inc.

Trouble Shooting ENC 125 T/E

If you experience difficulties with your installation, do the
following to determine the problem.

Checking the Readout

Difficulties on more than one axis are usually associated with
the readout. Follow these steps to determine if your
difficulties are associated with the readout:

• Insure that the linear encoder connectors are correctly
seated.

• Swap linear encoder cables at the readout to see if the
problem is still shown in the same display.

• If the problem remains in the same display, the readout is
in error.

• If the problem follows the connection change, the linear
encoder may be in error.

If the Readout is at fault, refer to “What to do” to arrange for
the parts necessary to repair your system. If a linear encoder
appears to be at fault, proceed with “Checking the Linear

Encoders”.

Checking the Linear Encoders

Problems on a single axis are usually associated with the
linear encoder or its installation. Difficulties can be caused
by improper installation, loose or misaligned bracketry, or a
damaged or inoperable encoder.

Follow these steps to determine the cause of your system
difficulties:

• Confirm that your bracketry and installation does not
interfere with other machine structures through the entire
length of the linear encoder travel.

• Check for loose fasteners. If you find loose fasteners, first
confirm that the linear encoder is installed to the
tolerances specified and then retighten the fasteners as
required.

• Confirm that the linear encoder is installed to the required
tolerances by checking the alignment tolerances specified
on Page 4. If the installation does not meet the tolerances,
reinstall the encoder according to the “Installation
Procedure”.

• Perform a Repeatability Test as described on Page 11. If
the linear encoder is installed to the required tolerances,
the bracketry and encoder have been checked for
interferences and loose fasteners, and the encoder fails the
repeatability test, the encoder is likely at fault.

Do not attempt to repair the reading head or scale assembly.
The ENC 125 is field serviceable by assembly replacement
only. Attempts to repair the encoder can permanently
damage it and void the warranty.

What to do

If an Acu-Rite Companies Inc. linear encoder or readout is
found to be at fault, please contact your authorized
Distributor for instructions prior to removing the encoders or
readout .

Acu-Rite Companies Inc. 14

ENC 125 T/E Mechanical Specifications

Mechanical Specifications Digital

Resolution 5µm, & 10µm
Grating pitch 40 µm
Scale medium Light transmission through chrome-coated glass

Accuracy (@ 20° C) ± 10µm/ 1000mm
Max. slew speed 30 inches/sec
Force required to move

reading head

Operating Environment:
Temperature 0° to 40° C
Relative Humidity 25% to 95% (non-condensing)

Storage Environment:
Temperature -20° to 65° C
Humidity 20% to 95% (non-condensing)

Weight w/cable ENC 125 T 1.3 lbs. + 0.05 lbs/in of measuring length

Weight w/cable ENC 125 E 1.3 lbs. + 0.11 lbs/in of measuring length
Connecting Length = 13 ft (4m) cable for ML <42”

Braided cable Length = 19 ft (6m) cable for ML >42”

Max. cable length 35 ft
Measuring lengths - ENC 125 T 2” - 120”

Measuring lengths - ENC 125 E 2” - 22”

Reference Pulse Interval 200mm

Repeatability Within one resolution count

Protection (IEC 529) IP 53 when installed as per instructions

15 Acu-Rite Companies Inc.

< 0.75 lbs

Connector: DE-9P

Output Signals and Pin-Outs ENC 125 T/E

Digital Differential

Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Pin 8 Pin 9

- Green - Blue - White Brown Pink -

Channel Channel Ground Vcc, + 5.1 Channel

A+ B+ ± 0.1 VDC R+

1

6

Acu-Rite Companies Inc. 16

5

9

ENC 125 T/E Electrical Specifications

Parameter Digital

Output Signals

Incremental signals

Signal levels

Reference Mark signals

Signal level

Power Supply

IOH=(High level output current) = 20mA
VOH=(High level output voltage) >2.5Vdc

360°0°

Channel A+

Channel B+

1
0

90°

1
0

Square-wave voltage signals.

Channels A and B, in 90°

quadrature relationship

Square-wave pulse

5.1 ± 0.1 VDC @ 100 mA max.

Channel R+

1 Count

TTL-level

TTL-level

1
0

=(Low level output current) = 20mA

I

OL

VOL=(Low level output voltage) < 0.5Vdc

17 Acu-Rite Companies Inc.

Warranty ENC 125 T/E

Acu-Rite Companies Inc. products and accessories are
warranted against defects in material and workmanship for a
period of three years from the date of purchase. Acu-Rite
Companies Inc. will, at its option and expense, repair or
replace any part of the Acu-Rite Companies Inc. product
which fails to meet this warranty. This warranty covers both
materials and factory service labor. In addition, authorized
Acu-Rite Companies Inc. service representatives will provide
service labor (field service) for a one-year period at no charge.
Notice of the claimed defect must be received by Acu-Rite
Companies Inc. within the warranty period.

This warranty applies only to products and accessories
installed and operated in accordance with this reference
manual. Acu-Rite Companies Inc. shall have no obligation,
with respect to any defect or other condition caused in whole
or part by the customer's incorrect use, improper
maintenance, modification of the equipment, or by the repair
or maintenance of the product by any person except those
deemed by Acu-Rite Companies Inc. to be qualified.

Responsibility for loss of operation or diminished performance
due to environmental conditions such as humidity, dust,
corrosive chemicals, deposition of oil or other foreign matter,
spillage, or other conditions beyond Acu-Rite Companies
Inc.'s control can not be accepted by Acu-Rite Companies Inc.

There are no other warranties expressed or implied, and
Acu-Rite Companies Inc. shall not be liable under any
circumstances for consequential damages.

3 Year Hassle Free Warranty

Keep the box and packing materials
Acu-Rite Companies Inc. is proud to offer the 3 Year Hassle-

Free Warranty for all precision glass scales. This warranty
will cover all of the Acu-Rite Companies Inc. repair and
replacement costs for any precision glass scale returned
during the three-year warranty period. Acu-Rite Companies
Inc. will repair or replace the damaged components ­regardless of the product’s condition absolutely free, no
questions asked.

Acu-Rite Companies Inc. 18

Notes

19 Acu-Rite Companies Inc.

Notes

Acu-Rite Companies Inc. 20

Acu-Rite Companies Inc.Acu-Rite Companies Inc.

Acu-Rite Companies Inc.

Acu-Rite Companies Inc.Acu-Rite Companies Inc.

IS ANIS AN

IS AN

IS ANIS AN

ISO 9001ISO 9001

ISO 9001

ISO 9001ISO 9001

CERTIFIEDCERTIFIED

CERTIFIED

CERTIFIEDCERTIFIED

MANUFMANUF

ACTURERACTURER

MANUF

ACTURER

MANUFMANUF

ACTURERACTURER

Acu-Rite Companies Inc.

One Precision Way • Jamestown, NY 14701

516289-20 5/06