Rockwell Automation 57C422B 2 Axis Servo Module - Manual (Page 16)

2-6 2-Axis Servo Module M/N 57C422B
In order to provide a current or velocity reference to the servo
drive panel, each axis on the module contains a voltage
output. The voltage output has a range of +10 Volts and
requires an externally mounted +12 or +15 volt power
supply. The voltage output is separately isolated for each
channel. Refer to figure 3.6 for a typical output circuit and
isolated power supply connections