Rockwell Automation 1746-HSRV SLC Servo Control Module User Manual - Manual (Page 57)

Publication 1746-6.1.2 - July 2000
5-14 Wiring the SLC Servo Module
by the manufacturer. Those limits for the 845H are a minimum voltage
requirement of 4.75V and a maximum voltage of 5.25V.
To meet the voltage requirement of the encoder and still attain
maximum cable length, you can do the following:
•
Raise the voltage of the power supply to meet the encoder
requirement without exceeding the 5.25V limit of the SLC Servo
Module, measured at the module.
•
Increase the gage of the wire connecting the termination panel
to the encoder (12 AWG maximum).
Figure 5.11 shows a circuit equivalent for channel A.
Figure 5.11 Encoder Feedback Equivalent Circuit
IMPORTANT
The term user-side refers to the control circuitry on
the SLC Servo Module card that is powered by
user-supplied power sources and isolated from the
control circuitry powered by the backplane of an SLC
rack.
+5V
+5V
A
A
C ontrol Module
C h A H I
C h A LO
Termination P anel
+
-
0.01 microfarads
1746-HCA
768 ohms
768 ohms
221 ohms
Differential
Line Driver
Customer
Encoder