32

Possible Causes

• •Broken voltage sense leads
• •Control fault
• •Dirty or loose battery cable connections
• •Discharged or depleted battery
• •External shorts
• •Faulty battery charging system
• •Faulty generator brush block and slip rings
• •Faulty generator rotor
• •Faulty generator stator assembly
• •Faulty genset control PCB
• •Fuel supply issue
• •High engine oil viscosity
• •Loose voltage sense leads
• •Mechanical engine damage
• •Open circuit across pins P1-1 and P1-10 (field windings)
• •Open circuit across pins P1-3 and P1-9 (quadrature windings)
• •Rotor resistance open, short, or ground
• •Stator resistance open, short, or ground

Suggested Actions

1. 1Check AC output
2. 2Check battery connection to battery & set
3. 3Check battery voltage to set
4. 4Check field resistance
5. 5Check fuel supply
6. 6Check mechanical engine damage
7. 7Check rotor resistance (opens/shorts/grounds)
8. 8Check stator resistance
9. 9Check stator resistance (opens/shorts/grounds)
10. 10Check voltage sense leads
11. 11Clean and tighten the positive (+) and negative (-) battery cable connections at the battery and at the genset
12. 12Disconnect genset control connector P1 and check for electrical continuity across pins P1-1 and P1-10 (field windings). If open, service the generator brush block and slip rings and repeat the test. Service or replace the generator rotor if the circuit is still open.
13. 13Disconnect genset control connector P1 and check for electrical continuity across pins P1-3 and P1-9 (quadrature windings). Replace the generator stator assembly if the circuit is open.
14. 14Recharge or replace the battery
15. 15Replace the engine oil with oil of proper viscosity for the ambient temperature
16. 16Replace the genset control PCB
17. 17Test the battery charging system and service as necessary
18. 18Troubleshoot Control
19. 19Troubleshoot external shorts

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