Cummins/Onan — Periodic Running Test (Generator Set Exercise)
Maintenance · GenSet and Transfer Switch
From a Cummins/Onan service manual — check it applies to your exact model before use.
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Before you start
- Exhaust gas is deadly; shut down the GenSet immediately if an exhaust leak is detected.
- Fuel and oil leaks can create hazardous conditions that can cause serious injury.
Procedure
- At the GenSet, place the Remote/Stop/Run switch to RUN; the GenSet will start.
- While running, check for visual and audible exhaust system leaks and the security of exhaust supports; repair if found.
- Check the GenSet visually for fuel, oil, or coolant leaks; repair if found.
- After approximately 10 minutes (operating temperature), record oil pressure, oil temperature, coolant temperature, and battery charge rate.
- Operate the Phase Selector switch to read generator outputs and record the meters.
- Open the transfer switch cabinet door and move the Motor Disconnect switch to Off.
- Manually transfer the load between Normal and Emergency using the operator handles.
- Move the Motor Disconnect switch back to Auto and close the cabinet door.
- At the GenSet, place the Remote/Stop/Run switch to STOP.
Specs & values
- Run at least 30 minutes once each week with at least 50 percent load
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.