Cummins/Onan — A.C. Voltage Regulator Adjustment
Adjustments
From a Cummins/Onan owner's manual covering: 10HQ, 10HQ-150R, 15HQ, 15HQ-150R, 15HQ-4R30. Check it applies to your exact model before use.
Applies to: Cummins/Onan 10HQ, Cummins/Onan 10HQ-150R, Cummins/Onan 15HQ, Cummins/Onan 15HQ-150R, Cummins/Onan 15HQ-4R30, Continental F162 engine
Before you start
- Never change factory settings of the regulator springs or contact fingers.
Procedure
- Snap toggle switch to RHEOSTAT ON position.
- Adjust manual rheostat for 70 volts exciter voltage across dc brushes A1 and A2.
- Shift brush rig to position giving the highest voltage (neutral).
- Adjust manual rheostat to obtain rated AC voltage.
- Snap toggle switch to REGULATOR ON position.
- Set regulator rheostat at approximately middle of rotation.
- Set adjustable resistor to obtain rated AC voltage; retighten clip.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Exciter voltage 70 volts
- Adjustable range not less than 10% above and 10% below rated AC voltage
Full service-parts list: Cummins/Onan 10HQ →, Cummins/Onan 10HQ-150R →, Cummins/Onan 15HQ →, Cummins/Onan 15HQ-150R →, Cummins/Onan 15HQ-4R30 →, Continental F162 engine →
Source: Cummins/Onan owner'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.