Cummins/Onan — Frequency Adjustment
Adjustments · governor
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan NHEL
Before you start
- Disconnect voltage/frequency sensitive devices before adjustments.
Procedure
- Set altitude adjust knob (gasoline only) to your altitude.
- Disconnect all loads and check no-load frequency.
- Turn governor speed adjusting screw to obtain 62-63 Hz (51.5-52.5 Hz for 50 Hz).
- Check output voltage; see Generator if not within 10 percent of rated.
- See Troubleshooting if engine runs roughly.
Full service-parts list: Cummins/Onan NHEL →
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.