Generac

1901

UnclassifiedLubrication

What This Code Means

Undervoltage (both zero crosses missing for 1.5 seconds); Undervoltage (little / no voltage, <120V); Undervoltage (no field current but have DPE); Generator Shuts Down for Under Voltage; No RPM pulses sensed for 75 consecutive milliseconds while starter active; Cranking faults to RPM sensor loss; Starter engaged, no tooth pulses for 75 ms; While running, no tooth pulses for 75 consecutive milliseconds; Unit Overloaded or Fuel System issue; Low Fuel Pressure; Throttle Stuck Closed/near Closed; Undervoltage; No pulse during cranking (RPM sensor); No tooth pulses sensed for 75 consecutive milliseconds while starter active; No pulse during running (RPM sensor); Loss of RPM sensor signal while running; Missing pulses during cranking (RPM sensor); Missing pulses during running (RPM sensor); Underspeed condition detected (<83.3% speed (60 Hz) or <66.6% speed (50 Hz) for 30 seconds); Unit overloaded slowing engine speed; Underspeed condition detected; Low fuel pressure detected for 1200 ms bef

Possible Causes

  • •AVR voltage communication failure or incorrect voltage reported via communication line
  • •AVR voltage information sent to Evolution controller via communication lines
  • •AVR voltage reported low to controller via communication line for 10+ seconds
  • •AVR voltage reported low via communication line
  • •Brush failure
  • •Circuit in general
  • •Communication line issue between AVR and Evolution controller
  • •Controller measuring no voltage
  • •Faulty AC Sensing Circuit
  • •Faulty Brushed Rotor Assembly
  • •Faulty DB1 Diode
  • •Faulty DB2 Diode
  • •Faulty DPE Breaker
  • •Faulty DPE Circuit
  • •Faulty Fixed Excitation Circuit
  • •Faulty Flash Wiring
  • •Faulty Main Circuit Breaker
  • •Faulty Regulator Output
  • •Faulty Rotor Insulation Resistance
  • •Faulty Stator
  • •Faulty excitation winding
  • •Faulty zero cross circuit
  • •Field boost hardware failure
  • •Loose wiring
  • •Low voltage condition for 10+ seconds
  • •Low voltage condition sustained for 10+ seconds
  • •Undervoltage
  • •Undervoltage reported from AVR via communication line for 10+ seconds
  • •Undervoltage reported to controller from AVR via communication line
  • •Undervoltage value reported from AVR via communication line for 10+ seconds
  • •Undervoltage value reported to Evolution controller
  • •Undervoltage value reported to Evolution controller from AVR via communication line
  • •Voltage reported to the controller from the AVR via communication line is low for 10+ seconds
  • •Wire loose

Suggested Actions

  1. 1Check communication wires between AVR and Evolution controller
  2. 2Perform Rotor Insulation Resistance Test
  3. 3Perform Test 2
  4. 4Repair or Replace Rotor
  5. 5Repair or Replace Wire 14
  6. 6Replace Controller
  7. 7Replace Rotor Only
  8. 8Replace Rotor and Stator
  9. 9Replace Stator Only
  10. 10Test AC Sensing Circuit
  11. 11Test Brushed Rotor Assembly
  12. 12Test DB1 Diode
  13. 13Test DB2 Diode
  14. 14Test DPE Breaker
  15. 15Test DPE Circuit
  16. 16Test Field Flash Circuit
  17. 17Test Fixed Excitation
  18. 18Test Flash Wiring
  19. 19Test Main Circuit Breaker
  20. 20Test Regulator Output
  21. 21Test Stator
  22. 22Test Wire 14 Field Flash Circuit
  23. 23Verify Generator output voltage in the Dealer Menu display of the Evolution controller

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