15

Possible Causes

• •Binding in the governor linkage
• •Blocked exhaust system
• •Control plugs not fully seated
• •Dirty or restricted air cleaner
• •Excessive connected loads
• •Faulty field windings
• •Faulty fuel solenoid valve operation
• •Faulty genset control PCB
• •Faulty governor actuator operation
• •Faulty governor controller board
• •Faulty ignition system
• •Faulty magnetic pick-up operation
• •Faulty start/stop switch (local and remote)
• •Fuel supply issues
• •Genset is loaded nearly to full power and a large motor load (such as an air conditioner) cycles on
• •Governor linkage binding
• •Grounded field windings
• •Grounded or shorted main windings
• •Improper field resistance (open to ground)
• •Improper loads
• •Improper quad winding resistance
• •Incorrect battery voltage
• •Incorrect engine speed
• •Incorrect engine speed (frequency)
• •Incorrect gas supply pressure
• •Incorrect loads
• •LPG fuel tank less than half full during cold weather (insufficient vaporization)
• •Large motor load draws up to three or more times its rated power consumption at startup
• •Open or shorted wiring
• •Opens and/or shorts in stator and rotor
• •Overload Condition
• •Poor brush condition and contact
• •Quad leads not fully seated in connector to control
• •Unsecured spark plug cable
• •Use of LPG with more than 2.5 percent butane below 32 °F (0 °C)
• •Worn or malfunctioning engine (low cylinder compression)

Suggested Actions

1. 1Check brush condition and contact
2. 2Check circuit breaker
3. 3Check control
4. 4Check engine speed
5. 5Check engine speed (frequency)
6. 6Check field windings
7. 7Check for a blocked exhaust system and service as necessary
8. 8Check for binding in the governor linkage
9. 9Check for grounded or shorted main windings
10. 10Check for proper field resistance reading, open to ground
11. 11Check fuel solenoid valve operation
12. 12Check fuel supply
13. 13Check governor actuator operation
14. 14Check loads
15. 15Check magnetic pick-up for proper operation
16. 16Check output voltage
17. 17Check quad winding resistance
18. 18Check stator and rotor for opens and/or shorts
19. 19Check that control plugs are fully seated
20. 20Check that quad leads are fully seated in connector to control
21. 21Check the gas supply pressure and adjust as necessary
22. 22Check the governor controller board
23. 23Check the governor linkage for binding and service as necessary
24. 24Conduct a cylinder compression test and service the engine if it is worn or malfunctioning
25. 25Conduct the ignition system tests and service as necessary
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. 28Limit the total load to not exceed 80% of the genset kW rating when powering large motor loads
29. 29Perform checks in step 01
30. 30Replace the genset control PCB
31. 31Service the air cleaner
32. 32Shut off some loads at times when large motor loads are active
33. 33Turn the genset line circuit breaker OFF and run the genset with fewer connected loads
34. 34Verify control plugs are fully seated
35. 35Verify quad leads are fully seated in connector to control

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