The controller indicates 'Field Overload' or 'Excitation Fault'; the generator may shut down or produce unstable voltage.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Shorted rotor windings, failed AVR driving too much current, shorted field wiring, control board fault.

Safety: Disconnect AC output and battery before accessing the generator end. Only qualified technicians should work on excitation circuits.

Inspect AVR: Remove and visually inspect the AVR for burnt components. Replace if damaged.
Check field resistance: Measure the resistance of the rotor field winding at the slip rings. Compare to Generac specifications. Very low resistance suggests a shorted rotor requiring replacement.
Inspect wiring: Check field leads from the AVR to the rotor for insulation damage or shorts to ground. Repair or replace as needed.
Controller check: If the rotor and wiring are good, the control board may be misdriving the AVR. Replace the controller if confirmed faulty.

Professional Required 5/5

Rotor Assembly

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