Manual

Rockwell Automation Publication 1407-UM001G-EN-P - April 2013 163
Troubleshooting Chapter 7
Protection
One or both CGCM units will not
operate as primary
Faulty wiring Measure excitation enable input to
CGCM unit that will not act as
primary
Verify voltage is applied to
excitation enable input terminal
Check operation of external relay
and associated wiring for
redundancy relay and output
Correct excitation redundancy relay
operation
Check wiring of excitation +/- output
from CGCM unit
Correct excitation output wiring
Logix controller error Check output to excitation enable
input (hardware and software)
Correct logic as required
Check logic to redundancy relay (if
applicable)
Correct logic as required
One CGCM unit has failed or is not
configured properly
Troubleshoot as non-redundant
CGCM unit
Correct or replace as needed
Table 32 - Redundancy
Symptom Most Likely Cause Diagnostic Action Corrective Action
Table 33 - Protection
Symptom Most Likely Cause Diagnostic Action Corrective Action
Loss of excitation current (40) Wiring error Check excitation output wiring Correct wiring as required
Gains mis-adjusted Check AVR gains Calculate/adjust gains as required
Over-excitation voltage (59F) Wiring error Check excitation output wiring Correct wiring as required
Gains mis-adjusted Check AVR gains Calculate/adjust gains as required
OEL limit exceeded Check OEL operation Correct as required
Generator over-voltage (59) Rapid loss of large load
Gains mis-adjusted Check AVR gains Calculate/adjust gains as required
Generator under-voltage (27) Over load
Wiring error Check VT wiring. See Voltage
metering trouble shooting
Correct wiring as required
Loss of sensing (60FL) Fuse open Check VT fuses Replace as required
Wiring error Check for open connections and
phase rotation reversal
Correct wiring as required