AVR & Voltage Regulator Repairs.
Stable Power Restored.

The Automatic Voltage Regulator is the component responsible for maintaining stable output voltage regardless of load changes. When it fails, the symptoms range from complete loss of output voltage to fluctuating power that damages connected equipment. ProService Generator Repairs diagnoses and repairs AVR faults on the generator that is installed, across Gauteng.

AVR failures can result from age, heat exposure, power surges, moisture ingress, or manufacturing defects. A common misdiagnosis is assuming the alternator or engine is at fault when the generator produces no power — in many cases, the engine is running perfectly and only the AVR has failed. Accurate diagnosis using the correct test equipment prevents unnecessary and costly component replacements.

Our technicians test AVR output signals, excitation winding resistance, and voltage behaviour under load to isolate the fault precisely. Where the AVR unit is repairable, we replace failed internal components to restore function at lower cost than full replacement. Where replacement is the correct solution, we source a compatible unit matched to your specific alternator — correct matching and calibration are critical, as an incorrectly matched AVR causes the same problems as the failed one.

After installation, every AVR repair is completed with calibration and a full load-range verification test. We confirm stable voltage output at light, medium, and heavy load before closing the job. This ensures the repair holds under real operating conditions, not just at idle.

Alternator brands worked on include Stamford, Leroy Somer, Mecc Alte and Marathon. An unlisted alternator is assessed on the unit. Where a replacement AVR is the right repair, it is matched to that alternator and calibrated for it.