Westerbeke 65A-FOUR - Generator Troubleshooting (Chart)

GENERATOR TROUBLESHOOTING
NOTE: AC GENERATOR TROUBLESHOOTING MUST
BE PERFORMED WITH THE ENGINE OPERATING AT 60 HZ.
FAULT PROBABLE CAUSE
NO AC VOLTAGE OUTPUT AT NO LOAD. 1. Short or open in the
4. Open in exciter
main stator winding. stator winding.
2. Shorted suppressor 5. Open in rotating
on exciter rotor. field winding.
3. Four or more shorted or 6. Shorted condenser
open diodes on exciter rotor. on exciter rotor.
RESIDUAL VOLTAGE PRODUCED AT 1. Blown 6 AMP fuse
3. Shorted or open main
NO LOAD 15 • 20 VOLTS AC.
auxiliary circuit feed to AVA.
stator auxiliary winding.
2. Faulty voltage regulator
LOW AC VOLTAGE OUTPUT AT
1. Reset voltage potentiometer. 4. Faulty voltage regulator.
NO LOAD 60 • 100 VAC.
2. Open or shorted diodes in.
exciter rotor 1 to 3 diodes.
5. Short in rotating field winding.
3. Open or short in one of the three 6. Short in the exciter stator.
exciter rotor windings.
HIGH AC OUTPUT VOLTAGE
1. Reset voltage potentiometer.
150 VAC OR HIGHER.
2. Faulty voltage regulator.
UNSTABLE VOLTAGE OUTPUT.
1. STB pod on regulator 2. Faulty voltage regulator.
(ENGINE SPEED STEADY) needs adjustment.
AC VOLTAGE DROP UNDER LOAD 1. Diode(s) on exciter rotor
60 ·100 VOLTS AC. breaking down when load is
applied (inductive) 1·3 diodes.
Engines & Generators
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