36

Possible Causes

• •Broken or loose wiring connections
• •Broken voltage sense leads
• •Broken wiring connections
• •Configuration plug P8 not fully seated
• •Control plugs not fully seated
• •Dirty air cleaner
• •Dirty generator brush block and slip rings
• •Exciter rotor failure
• •Faulty S5 switch
• •Faulty generator rotor
• •Faulty genset control PCB
• •Fuel solenoid valve malfunction
• •Fuel supply issue
• •Governor actuator operation issue
• •Grounded or shorted field windings
• •Grounded or shorted quad windings
• •Ignition system malfunction
• •Incorrect control part number
• •Incorrect gas supply pressure
• •Incorrect loads
• •LPG fuel tank less than half full in cold weather or incorrect LPG grade
• •Loose pin connections to controller
• •Loose spark plug cable
• •Loose voltage sense leads
• •Loose wiring connections
• •Magnetic pick-up malfunction
• •Main rotor failure
• •Mechanical engine damage
• •Open circuit across field windings (pins P1-1 and P1-10)
• •Output voltage issue
• •Overload Condition
• •Quad leads not fully seated in connector to control
• •Rotating diode assembly failure
• •Worn or malfunctioning engine (low cylinder compression)

Suggested Actions

1. 1Check brush condition and contact
2. 2Check continuity through S5 switch at idle and during operation
3. 3Check exciter rotor
4. 4Check field windings
5. 5Check for broken or loose wiring connections
6. 6Check for grounded or shorted field windings
7. 7Check for grounded or shorted quad windings
8. 8Check for mechanical engine damage
9. 9Check for proper field resistance reading, open to ground
10. 10Check fuel solenoid valve operation
11. 11Check fuel supply
12. 12Check gas supply pressure and adjust as necessary
13. 13Check governor actuator operation
14. 14Check loads
15. 15Check magnetic pick-up for proper operation
16. 16Check main rotor
17. 17Check mechanical engine damage
18. 18Check output voltage
19. 19Check pin connections to controller
20. 20Check rotating diode assembly
21. 21Conduct a cylinder compression test and service the engine if it is worn or malfunctioning
22. 22Conduct ignition system tests and service as necessary
23. 23Disconnect genset control connector P1 and check for electrical continuity across pins P1-1 and P1-10; service generator brush block and slip rings if the circuit is open
24. 24Ensure control plugs are fully seated
25. 25Ensure quad leads are fully seated in connector to control
26. 26Fill the LPG fuel tank if less than half full and use HD-5 grade LPG
27. 27Inspect and secure the spark plug cable on the spark plugs
28. 28Replace the genset control PCB
29. 29Service or replace generator rotor if field winding circuit remains open
30. 30Service the air cleaner
31. 31Verify configuration plug P8 is fully seated
32. 32Verify control plugs are fully seated
33. 33Verify quad leads are fully seated in connector to control

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