The HA is a generator-set controller. It is used on generator sets from Cummins/Onan, including the 15.0 HA and 7.5 HA.
Also fitted to: Cummins/Onan 15.0HA-23/24D, Cummins/Onan 15.0HA-23/25D, Cummins/Onan 7.5HA-21/24D, Cummins/Onan 7.5HA-21/25D, Cummins/Onan 7.5HA-23/24D, Cummins/Onan 7.5HA-23/25D.
| Symptom | Cause | Remedy |
|---|---|---|
| Automatic demand control will not start generator set with load (Spec C) | Auto-manual switch not at "AUTO" or elec-start switch not at "ELEC START" | Check switch positions. Auto-manual switch should be set at "AUTO," elec-start switch at "ELEC START." |
| Automatic demand control will not start generator set with load (Spec D) | Auto-manual switch not at "AUTO" or elec-start switch not at "ELEC START" | Check switch positions. Auto-manual switch should be set at "AUTO," elec-start switch at "ELEC START." |
| Bilge blower does not operate when load is connected (Spec D) | Auto-manual switch not at "AUTO" or elec-start switch not at "ELEC START" | Check switch positions. Auto-manual switch should be at "AUTO", elec-start switch at "ELEC START." |
| Bilge blower time delay timer does not operate | 6.25-ampere fuse blown | Before testing the timer, always check the 6.25-ampere fuse to see if it has blown. If the fuse is okay, connect a DC voltmeter between B+ and time delay terminal 3 on the terminal block. At the end of the time delay, the voltmeter should indicate battery voltage. The DC voltmeter connected between B+ and time delay terminal 2 should now read zero volts. |
| Control will not start the generator set when minimum load is applied (Spec A only) | Minimum starting load set too low | Adjust the variable resistor (Figure 4-18) on the terminal board (left side—two wire models). Turn the adjustment screw with a Phillips screwdriver clockwise to increase minimum starting load, counterclockwise to decrease minimum starting load. Adjust starting resistor in small steps and check adjustments often to avoid cycling. |
| Demand control will not keep the generator set running with the minimum load (Spec A only) | Load required for operation set too high | Adjust the variable resistor on the terminal board (Figure 4-18). Turn the adjustment screw with a Phillips screwdriver counterclockwise to decrease load required for operation. |
| Generator set starts but does not assume load (Spec C) | Incorrect generator output voltage | Check generator output voltage. See generator set operator's manual. |
| Generator set starts but does not assume load (Spec D) | Incorrect generator output voltage | Check generator output voltage. See generator set operator's manual. |
| Generator set starts but stops when line contactor pulls in (Spec C) | Control circuit fault | Move auto-manual switch to "MANUAL" position. Connect a jumper from terminal 6 to terminal 1. Move auto-manual switch to "AUTO" position. Generator set should start and run. |
| Generator set starts but stops when line contactor pulls in (Spec D) | Control circuit fault | Move auto-manual switch to "MANUAL" position. Connect a jumper from terminal 6 to terminal 1. Move auto-manual switch to "AUTO" position. Generator set should start and run. |
| Generator set will not stop when load is removed (Spec C) | Sufficient load keeping the control energized | Put auto-manual switch in "MANUAL" position and stop generator set with start-stop switch on engine control. Remove the lead from the load side of the contactor in the demand control. Move the auto-manual switch to "AUTO." If engine cranks, proceed to Step 5. If engine doesn't crank, put auto-manual switch to "MANUAL" position. Start engine with engine start-stop switch. Move auto-manual switch to "AUTO" position and generator set should stop. This indicates there was sufficient load to keep the control energized. Check load circuit for loads. |
| Generator set will not stop when load is removed (Spec D) | Sufficient load keeping the control energized | Put auto-manual switch in "MANUAL" position and stop generator set with start-stop switch on engine control. Remove the lead from the load side of the contactor in the demand control. Move the auto-manual switch to "AUTO." If engine cranks, proceed to Step 5. If engine doesn't crank, put auto-manual switch to "MANUAL" position. Start engine with engine start-stop switch. Move auto-manual switch to "AUTO" position and generator set should stop. This indicates there was sufficient load to keep the control energized. Check load circuit for loads. |
| Line contactor will not pull in when the generator set starts, or pulls in at too low a voltage causing the generator set to cycle | Line contactor pull-in voltage incorrectly adjusted | Adjust the adjustable resistor in series with the line contactor coil (Figure 4-19). This is factory adjusted to pull in when the generator voltage reaches 102 to 108 volts (204 to 216 volts on 240-volt models). Do not adjust this resistor unless the line contactor will not pull in when the generator set starts or if it pulls in at too low a voltage causing the generator set to cycle. |
| Load sensor believed to be the source of a control malfunction | Load sensor amplifier fault | Use the troubleshooting procedures for checking components. Potentiometers (Spec A only) for adjusting starting and running are mounted on the board. |
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.