Allen-Bradley 1407-CGCM-DLR, User Manual, Page: 168 / 268

168 Rockwell Automation Publication 1407-UM002B-EN-P - February 2019
Chapter 7 Troubleshooting
Table 23 - Compensation Modes - Droop
Symptom Most Likely Cause Diagnostic Action Corrective Action
Voltage does not change with
changes in reactive load while not
connected to the grid Droop not selected/active Check tag Droop_Ened If not active, check/correct logic for
mode selection
Cross current mode is
enabled/selected Check Droop_CCCT_Select tag If active, check/correct logic for
mode selection
Metering error See Metering troubleshooting
Table 30
See Metering troubleshooting
Table 30
Reactive power does not change
with adjustments to the voltage
setpoint while connected to the grid Droop not selected/active Check tag Droop_Ened If not active, check/correct logic for
mode selection
PF or VAR control enabled/selected Check tag PF_VAR_Control If active, check/correct logic for
mode selection
Metering error See Metering troubleshooting
Table 30
See Metering troubleshooting
Table 30
Voltage and / or reactive load is
unstable when operating in droop AVR Gains misadjusted Check voltage stability when
operating isolated from load and if
possible in constant voltage control Calculate/correct AVR gains if
necessary
Metering error See Metering troubleshooting
Table 30
See Metering troubleshooting
Table 30
Table 24 - Compensation Modes - Cross Current
Symptom Most Likely Cause Diagnostic Action Corrective Action
VARs share but not equally; even
when the system load changes Gain mis-adjustment Check CCCT Gain Correct as required
CT or input impedance mismatch Verify CT selection and measure
input impedance to each AVR Correct or replace CTs as required.
Add resistors as required to match
AVR input resistance
VARs do not share at all and when a
voltage adjust is made, nothing
happens Cross current mode is not
enabled/selected Check Droop_CCCT_Select tag If not active, check/correct logic for
mode selection
Gain misadjustment Check CCCT Gain Correct as required
Wiring error Measure voltage at ID+/- terminal
and adjust reactive power/voltage Correct wiring as required if voltage
signal from CCCT circuit is not
observed