Controller shows AL14 indicating generator overvoltage; output voltage exceeds setpoint.

Safety first: Isolate the generator from load and lock out the main breaker. High voltage can damage connected equipment.

• Inspect AVR connections: Open the alternator terminal box and check all AVR wiring for tightness and signs of overheating. Ensure sensing leads are correctly connected to the designated terminals.
• Check AVR settings: Locate the voltage adjustment potentiometer on the SDMO AVR. If recently adjusted, return it to the factory setting. Do not over-adjust; small changes can cause large voltage shifts.
• Test alternator sensing: Measure the actual line voltage with a calibrated meter and compare to the controller reading. If the AVR is driving voltage too high despite correct sensing, replace the AVR.
• Inspect excitation circuit: Check brushes and slip rings (if brush-type alternator) for wear or contamination. Clean and replace as needed.
• Reset AL14: After stabilizing voltage, clear the alarm and perform a load test while monitoring voltage closely.