TROUBLESHOOTING – GENERATOR
As with any machine, trouble may develop in electrical generators. It may be due to long service or neglect of regular maintenance. Servicing, and checking. Should trouble develop, the follow- ing instructions will be helpful in tracing the cause and making repairs.
SPEED DEVIATIONS:
The generator speed should be maintained at rated nameplate speed. The frequency and volt- age of the generator output depends on speed. If the generator runs slower than rated speed, the voltage will drop off.
NO VOLTAGE |
|
CAUSE | CHECK AND REMEDY |
Loss of residual magnetism in | Flash Field. |
exciter field poles. |
|
Open in stator windings | Check for continuity in windings. Return to factory |
| for repair if open |
Open or short in rotating rectifiers. | Check rectifiers. |
Short Circuited. | Clear lead to restore voltage |
Open in alternator field | Check for continuity and return rotor to factory for |
| repair if field coils are open. |
Shorted exciter armature | Check for short and replace if faulty. |
Shorted leads between exciter | Test and repair |
armature and generator field. |
|
LOW VOLTAGE | |
CAUSE | CHECK AND REMEDY |
Excessive load. | Reduce load. With 3 phase generators, the load on |
| each leg should be as evenly balanced as possible |
| and should not exceed the rated current on any leg. |
Low Speed. | Check engine for malfunction or system for over- |
| load. |
Line loss. | Increase size of line lead wire. |
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