E012
Atlas Copco Generator Overvoltage Protection Trip

Atlas Copco controller indicates E012 Overvoltage and trips the generator breaker

Advertisements

Safety Warning

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.

Advertisements

Possible Causes

Faulty AVR (Automatic Voltage Regulator), Incorrect AVR sensing wiring, Loose or broken voltage reference leads, Incorrect voltage setpoint

How to Fix / Troubleshooting

Safety first: Overvoltage can damage connected equipment. Keep the generator isolated from the load until the cause is resolved. Only qualified personnel should access live terminals.

  • Measure output voltage: With a true RMS meter, measure line‑to‑line voltage at the generator terminals while running unloaded. Compare to the nameplate rating.
  • Inspect AVR: Locate the AVR in the alternator terminal box. Check for burnt components, loose connectors, or signs of overheating.
  • Check sensing leads: Ensure the AVR sensing wires are correctly connected to the proper phases and tight. A broken neutral or sensing lead can cause overvoltage.
  • Adjust voltage setpoint: If the AVR has an accessible voltage potentiometer, reduce the setting slightly and re‑measure. Follow Atlas Copco procedures for adjustment.
  • Replace AVR: If voltage remains unstable or excessively high, replace the AVR with the correct Atlas Copco‑specified part.

After repair, test under load and verify voltage remains within tolerance.

Advertisements

Repair Difficulty

Hard 4/5

Required Part

Automatic Voltage Regulator (AVR)
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements