Generator starts and runs but does not transfer power to the house or building

Safety: The ATS handles live utility and generator power. Only work inside the ATS if you are qualified. Otherwise, limit checks to external indicators and call a professional.

• Check ATS status indicators: Observe LEDs or display on the CAT-branded ATS. Confirm it recognizes generator availability.
• Verify generator breaker: Ensure the generator output breaker is ON. A tripped breaker will prevent transfer.
• Inspect ATS control power: If trained, open the ATS and check low-voltage control fuses and power supply modules. Replace blown fuses only after identifying the cause.
• Manual operation test: Many ATS units have a manual transfer handle. With both utility and generator sources safely isolated (per CAT and local procedures), exercise the mechanism to ensure it moves freely.
• Confirm wiring: Compare generator-to-ATS control wiring to the CAT wiring diagram to ensure the start and availability signals are correctly landed.

If the ATS still will not transfer automatically or manually, its controller or mechanism may be defective and should be serviced by a CAT technician or licensed electrician.