Controller displays 'Overcurrent' or 'High Current' and trips the generator breaker during operation.

Safety: De-energize both generator and utility sources. Lock out and tag out breakers if possible. Use caution when testing for shorts.

• Isolate loads: Open branch breakers in the building panel and attempt to run the generator with only a few circuits at a time. If the fault appears only with a specific circuit, inspect that circuit for shorts.
• Inspect ATS: Open the Generac transfer switch and check for burned contacts, melted insulation, or loose lugs. Replace damaged components or the entire switch if necessary.
• Test stator: With the generator off and disconnected, measure insulation resistance of stator windings to ground using a megohmmeter. Low insulation resistance indicates internal faults requiring stator replacement.