Basler Electric DECS-400 - Manual (Page 163)

9369700990 Rev R 151
High Generator Voltage (In AVR Mode)
Check the for the following settings:
a. AVR voltage setpoint
b. AVR Kg loop gain (too high)
c. Generator potential transformer (PT) primary voltage
d. Generator PT secondary voltage
e. Accessory inputs (should be zero)
f. Var/PF and droop should be disabled
If the problem persists, contact Basler Electric Technical Sales Support for advice.
Generator Voltage Unstable (Hunting)
Verify that the exciter power converter is working correctly by substituting the appropriate battery voltage
in place of the DECS-400 drive voltage. If the problem is caused by the DECS-400, check the gain
settings for the specific mode of operation selected.
If the problem persists, contact Basler Electric Technical Sales Support for advice.
Poor Voltage Regulation
Poor voltage regulation may result from insufficient K
g
loop gain. Increase the AVR loop gain accordingly.
No Buildup in FCR Mode
Low K
g
loop gain may hinder buildup when operating in FCR mode. An FCR loop gain of 150 or greater
may be necessary.
No Control Signal at Firing Circuit Input
Check the control signal setting and output of the DECS-400. Depending on the signal selected, the
DECS-400 will produce a 0 to 10 Vdc, 4 to 20 mAdc, or –10 to +10 Vdc control signal.
Limiters Do Not Limit at the Desired Level
Insufficient K
g
loop gain for the limiters may hinder limiter operation. Increase the limiter loop gain
accordingly.
Poor Reactive Control
Poor reactive control may result if the AVR droop setting is too low. Adjust the AVR droop accordingly.
Protection or Limit Annunciation
If a protection function or limiting function is annunciated, check the associated setting values.
If the problem persists, contact Basler Electric Technical Sales Support for advice.
Metering Readings Incorrect
If your PF, var, or watt readings are significantly different from the expected readings for a known load,
verify that the CT for phase B is actually placed on the phase B input to the DECS-400 and not or phase
A or C.
No Communication
If communication cannot be initialized, check the serial cables to the port connections, the transmission
speed (baud rate), and supporting software.
Real-Time Clock Information Lost After Loss of Control Power
A loss of real-time clock information indicates a depleted backup battery. See Backup Battery
Replacement for the battery replacement procedure.
DECS-400 Maintenance