Integrating a linear feedback device – Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set User Manual

Page 739

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Appendix

B

B-1

Integrating a Linear Feedback Device

Two of the more common positioning feedback types supported by the
9/Series are rotary encoders and linear scales. This appendix is designed

as an overview to help you get the necessary information into the system to

make your linear scale work.

The 9/Series is designed to support these three major styles of linear scales:

A quad B with no marker -- since this type of feedback device has no
marker, homing to a reliable zero point is not possible. This device

should only be used on applications where relative (incremental)

positioning is all that is required.

A quad B with one marker -- this type of device has one marker located
at or near a mechanical home limit switch. It is important that no more

than one marker be observed with this type of feedback device.

A quad B with distance coded markers -- this selection is only available
for 9/440HR systems. This feedback device is equipped with multiple

markers at progressively increasing distances along its length. This

allows the CNC to identify absolute axis position whenever three

consecutive markers are passed.

These linear feedback types can be used to close the position loop on both

digital and analog servos. On digital systems the velocity loop must

always be closed by the factory installed rotary feedback device mounted

directly on the motor shaft.

Input frequency, load, voltage, etc... must be compliant with those
specifications given for your specific 9/Series hardware as defined in your

9/Series integration manual for optional feedback devices. The following

linear feedback devices have been tested and are compatible as 9/Series

optional feedback:

Sony Magnescale (model GF--45E with broad--type detector MD10--FR)

Heidenhain (model 704 with external interpolation and digitizing model
EXE 602 D/5--F)

Heidenhain Distance Coded Marker Systems (model LS176)

B.0

Overview

B.1

Linear Feedback Device

Specifications

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