Basler Electric DECS-100 - Manual (Page 83)

9287500991 Rev M DECS-100 Maintenance and Troubleshooting 6-5
Step 3. Verify that the generator exciter field current requirements are compatible with the DECS-100.
If the generator exciter field current requirements are not compatible with the DECS-100,
contact Basler Electric Customer Service for recommendations.
If the generator exciter field current requirements are compatible with the DECS-100, proceed
to Step 4.
Step 4. Replace the DECS-100.
If replacing the DECS-100 does not correct the malfunction, proceed to Step 5.
Step 5. Refer to the generator manual. Generator is defective.
Underexcitation Limiting Indicator is Annunciating
Step 1. Verify that the DECS-100 generator voltage setpoint is not being driven to a lower level.
The setpoint can be affected by the Raise/Lower contact inputs or by the Auxiliary input.
Step 2. Verify that the DECS-100 output (field) current limit is not set too low.
Adjust the field current limit as needed.
Step 3. Use the connection diagrams of Section 4, Installation to verify that the sensing voltage and
current connections to the DECS-100 provide the proper phasing.
Correct the sensing voltage and current connections as needed.
Step 4. Verify that the generator exciter field current requirements are compatible with the DECS-100.
If the generator exciter field current requirements are not compatible with the DECS-100,
contact Basler Electric Technical Sales Support for recommendations.
If the generator exciter field current requirements are compatible with the DECS-100, proceed
to Step 5.
Step 5. Replace the DECS-100.
If replacing the DECS-100 does not correct the malfunction, proceed to Step 6.
Step 6. Refer to the generator manual or contact the generator manufacturer.
Underfrequency Active Indicator is Annunciating
Step 1. Verify that the generator is operating at rated speed.
If the generator is not operating at rated speed, adjust the generator speed.
If the generator is operating at the rated speed, proceed to Step 2.
Step 2. Verify that the underfrequency setpoint is correct.
If the underfrequency setpoint is incorrect, adjust it to the correct value.
No Droop
Step 1. Verify that the DECS-100 52L/M contact input is open.
If the 52L/M contact input is not open, it must be opened to enable the droop function.
If the 52L/M contact input is open, proceed to Step 2.
Step 2. Verify that the DECS-100 52J/K contact input (if present) is closed or the Var/PF function is
disabled via BESTCOMS™. Var/PF operation must be disabled for droop operation. If var/PF
operation is disabled, proceed to Step 3.
Step 3. Verify that the DECS-100 droop setting is not adjusted to 0% droop.
If the droop setting is adjusted to 0% droop, increase the setpoint above 0%.
If the droop setting is adjusted to above 0%, proceed to Step 4.
Step 4. Check for an open in the circuit connected to DECS-100 CT1 and CT2.
If there is an open circuit, repair as necessary.
If there is no open circuit, proceed to Step 5.
Step 5. Verify that all connections are correct according to Figures 4-6 through 4-9.
If connections are incorrect, correct the problem.