Controller shows E013 Undervoltage, generator breaker will not close

Safety first: Keep the generator isolated from the load while troubleshooting undervoltage. Lock out the breaker to prevent accidental closure.

• Check no‑load voltage: Start the generator with the breaker open. Measure line‑to‑line voltage. If significantly below rated, suspect excitation issues.
• Inspect AVR and excitation circuit: Verify all connections to the AVR, including field leads to the rotor. Look for burnt or loose terminals.
• Test with reduced load: If voltage collapses only under load, gradually apply load while monitoring voltage. A sudden drop may indicate a winding fault or undersized load step.
• Controller settings: Confirm the undervoltage threshold and delay are correctly set for your generator in the Atlas Copco controller.

If the alternator windings or rotor are suspected, further testing (insulation resistance, winding resistance) by a specialist is required.