Rockwell Automation 8520 9/Series Hardware TAB 5 - Manual (Page 102)

Section 5B
9/440HR CNC/Drive System
5B-28
Wiring an Incremental Feedback Device
Figure 5B.19 shows an incremental feedback device equivalent circuit for
feedback channel A.
Figure 5B.19
Incremental Feedback Device Equivalent Circuit for
A Quad B High–resolution Feedback Devices (J9 – J12)
Differential
Line Driver
Customer
Encoder
A
A
Termination Panel
9/440
8500-TPC
Cable
+5V
0 Ω
178
Ω
68pf
Zener
Protection
Encoder Return Optical Isolation
0V
+5V
0V
To Encoder Interface
CHA_HI
CHA_LO
Wiring Position Feedback
Feedback devices used with the control must be configurable such that the
marker Z is true at the same time that channels A and B are true. If you are
using an Allen-Bradley 845H encoder this requirement will already be met
if you wire them as shown in the cable diagrams on page
7A-63.
If you are using an encoder type feedback device other than the
Allen-Bradley 845H encoder, then use the following examples to
determine the correct wiring: