Cummins/Onan — Electric Governor Controller Adjustments
Adjustments
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan DGCA, Cummins/Onan DGCB, Cummins/Onan DGDA, Cummins/Onan DGDB, Cummins/Onan 4BT3.9Gl engine, Cummins/Onan 6BT5.9G2 engine, Cummins/Onan 4BT3.9G2 engine
Before you start
- If adjustment must be made while the unit is running, use extreme caution around hot manifolds and moving parts
Procedure
- Move RUN/STOP/REMOTE switch to RUN and operate set at no load.
- Confirm DROOP potentiometer adjust is set at zero position.
- Set speed by adjusting the SPEED potentiometer to 50 or 60 Hz.
- Adjust GAIN potentiometer clockwise until engine starts to hunt, then counterclockwise until speed is stable.
- Adjust the 'B' potentiometer the same as GAIN.
- Adjust the 'I' potentiometer to decrease overshoot above rated speed.
- Apply 1/4 load and adjust the GAIN potentiometer again.
- Apply full load to be certain the set will carry it; lengthen actuator linkage if it will not.
Tools required
- Frequency meter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Frequency set to 50 or 60 Hz
- Set should stop within 15 seconds
Full service-parts list: Cummins/Onan DGCA →, Cummins/Onan DGCB →, Cummins/Onan DGDA →, Cummins/Onan DGDB →
Source: Cummins/Onan operator's 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.