Allen-Bradley 1407-CGCM-DLR, User Manual, Page: 175 / 268

Rockwell Automation Publication 1407-UM002B-EN-P - February 2019 175
Troubleshooting Chapter 7
Redundancy
Protection
Table 33 - Redundancy
Symptom Most Likely Cause Diagnostic Action Corrective Action
Both CGCM-DLR units operate as
primary (both provide excitation to
the generator) Serial cable is not properly
connected Disable excitation to one
CGCM-DLR unit If excitation turns off as commanded
(one remaining unit operating),
repair / replace cable. If both units
continue to excite, replace
CGCM-DLR units
Connect personal computer by using
hyperterminal or similar application
to verify communication output from
CGCM-DLR unit redundancy comm
port If communication exists, see
Communication . If no
communication output exists,
replace unit
One or both CGCM-DLR units do not
operate as primary Faulty wiring Measure excitation enable input to
CGCM-DLR unit that does not act as
primary Verify that 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 exci/- output
from CGCM-DLR 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-DLR unit has failed or is
not configured properly Troubleshoot as nonredundant unit Correct or replace as needed
Table 34 - 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