Rockwell Automation 1771-QB Linear Pos. - Manual (Page 164)

Troubleshooting
Chapter 11
11Ć2
Module Fault Indicator
This red indicator is normally off. It turns on if there is a module fault in one
loop or both loops. Faults may be caused by:
loss of analog power
analog interface fault
memory fault
discrete input fault
transducer interface fault
excess following error
excess PID error
loss of feedback
hardware stop input
immediate stop command
Loop Active Indicators
Each of these green indicators is on when the corresponding loop is active. The
indicator blinks if a loop fault occurs and turns off if the loop is inactive.
Loop faults may be caused by loop failure or improper loop configuration.
Indicator Troubleshooting Guide
Refer to Table 11.A when using the indicators to diagnose module problems.