Generac

1905

UnclassifiedElectrical

What This Code Means

Generator Shuts Down for Under Voltage; Generator running underspeed for > 30 seconds when undervoltage alarm set; Single Zero Cross missing; Undervoltage due to faulty excitation winding, or zero cross circuit, or circuit in general; One zero cross missing for greater than 1.5 seconds; Field Current measured value is above threshold; The controller fuse is missing or damaged in such a way that it does not work; Fuse problem must be detected for 1.5 seconds; Command and position feedback not matching or taking too much time to achieve; Governor in open position for greater than one second; Governor in closed position (commanded otherwise) for greater than one second; Prolonged Undervoltage; Generator voltage below 80% of nominal for 10+ seconds.; Both Zero Crosses missing Undervoltage; Controller measuring no voltage resulting in undervoltage; Generator voltage less than 120V when undervoltage set; No field current during undervoltage alarm; Generator running underspeed for > 30 second

Possible Causes

  • •Faulty Main Circuit Breaker
  • •Faulty Fixed Excitation Circuit
  • •Faulty Rotor Insulation Resistance
  • •Faulty Regulator Output
  • •Faulty AC Sensing Circuit
  • •Faulty Brushed Rotor Assembly
  • •Faulty Stator
  • •Faulty DPE Breaker
  • •Faulty DPE Circuit
  • •Faulty Flash Wiring
  • •Faulty DB1 Diode
  • •Faulty DB2 Diode
  • •Faulty Wire 14 Field Flash Circuit
  • •Faulty Field Flash Circuit
  • •Faulty Controller
  • •Faulty Stator (when Rotor is good)
  • •Faulty Rotor (when Stator is good)
  • •Faulty Rotor and Stator
  • •Faulty Wire 14 (after tests indicate bad)
  • •governor wire loose

Suggested Actions

  1. 1Test Main Circuit Breaker
  2. 2Test Fixed Excitation
  3. 3Perform Rotor Insulation Resistance Test
  4. 4Test Regulator Output
  5. 5Test AC Sensing Circuit
  6. 6Test Brushed Rotor Assembly
  7. 7Test Stator
  8. 8Test DPE Breaker
  9. 9Test DPE Circuit
  10. 10Test Flash Wiring
  11. 11Test DB1 Diode
  12. 12Test DB2 Diode
  13. 13Test Wire 14 Field Flash Circuit
  14. 14Test Field Flash Circuit
  15. 15Replace Controller
  16. 16Replace Stator Only
  17. 17Replace Rotor Only
  18. 18Replace Rotor and Stator
  19. 19Repair or Replace Wire 14
  20. 20Repair or Replace Rotor

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