The Power Sentry logic is a generator-set controller. It is used on generator sets from Cummins/Onan, including the SC1802s.
| Symptom | Cause | Remedy |
|---|---|---|
| AFTER A POWER FAILURE, GENERATOR SET STARTS BUT DOES NOT ASSUME LOAD | 1. Check the output voltage of the emergency power source by observing the voltmeter on the generator set or the optional voltmeter on the automatic transfer switch. 2. Open the cabinet door and check to see if the Motor Disconnect switch is in the Auto position. 3. Check the Source 2 Available lamp on the Power Sentry to make sure that generator set power is being sensed. 4. Follow the Manual Operation procedures described in section 3. Call a service representative. | |
| AFTER POWER RETURNS, TRANSFER SWITCH DOES NOT RETURN TO NORMAL POSITION | 1. The retransfer time delay period may not have expired. Check the Retransfer Timing lamp on the Power Sentry 2. Open the cabinet door and check the Motor Disconnect switch position. For automatic operation, it should in the Auto position. | 3. Manually initiate retransfer by turning the Test/Normal/Retransfer switch to Retransfer. 4. Stop the generator set with the Start/Stop switch. When the generator set stops, the transfer switch will transfer load to the Normal power source if power is acceptable. Call your dealer or distributor. 5. If the switch still does not retransfer, follow the Manual Operation procedures described in section 3. Call your dealer or distributor. |
| GENERATOR SET CONTINUES TO RUN AFTER RETRANSFER OF LOAD TO NORMAL POWER | The stop time delay function may not have expired. Check the Stop Timing lamp on the Power Sentry. | Stop the generator set with its Start/Stop switch, and call your dealer or distributor. |
| GENERATOR SET DOES NOT EXERCISE (IF EQUIPPED WITH EXERCISER) | 1. Check the exerciser clock to see if it is in an exercise period. 2. Start the generator set using its start-stop controls. | |
| POWER OUTAGE OCCURS, BUT GENERATOR SET DOES NOT START | 1. Check the generator set. The operation selector switch on the generator set control panel should be set in the Remote position. Check for fault indicators on the generator set control. |
Fault codes and symptom→remedy steps extracted from this controller’s service/owner documentation; verify against the official manual before servicing. Aggregated from the service documentation of generator sets built on this controller.