Perkins generator controller shows E017 and indicates generator undervoltage

Safety: Ensure the generator is disconnected from the load before testing. Low voltage under load can damage connected equipment.

• Measure terminal voltage: Confirm the low voltage condition with a meter at the alternator terminals.
• Inspect AVR and wiring: Check the AVR connections for loose terminals, burnt components, or broken wires. Verify that the AVR has its required power supply (often from auxiliary windings).
• Field circuit check: With power off and following the alternator manual, measure resistance of the rotor field winding at the slip rings. An open circuit indicates a rotor fault.
• Check excitation fuse: Some alternators have fuses in the excitation circuit. Replace any blown fuses with the correct rating after identifying the cause.
• Replace AVR or alternator components: If the AVR has failed or the field winding is open, replace the AVR or repair/replace the alternator rotor as required.