Westerbeke 8.0KW-60Hz Service Manual page 62

COLISEUM GENERATOR
TROUBLESHOOTING
In some cases, it is difficult to find out on the basis of the
existing indications on which part of the generator the fault
has occurred. For this reason, it is recommended to follow
the step by step procedure below:
4. In case of a faulty regulator operation, the trouble may lie
ruso in the generator. This can be easily verified by
checking the generator operation with separate excitation.
For this check it is necessary to follow the EXCITATION
MAGNETIZATION PROCEDURE outlined on page 5 in
this manual.
1. Inspect visually the condition of all connections, tenninal
boards, terminals and the excitation system components.
2. Inspect visually for indications of damage to the
windings on the generator.
S. A burning smell or signs of smoke would indicate a short
in the windings or a mechanical failure.
3. Check the operation of the voltage regulator. Check if the
voltage.regulator is connected correctly and properly
adjusted.
FAULT
PROBABLE CAUSE
NO AC VOLTAGE OUTPUT AT NO LOAD. 1. Short or open in the 3. Open in exciter
main stator winding. stator winding.
2. Four or more shorted or
4. Open in rotating
open diodes on exciter rotor. fie,ld winding.
5. Shorted supressor.
RESIDUAL VOLTAGE PRODUCED AT
1. Faulty voltage regulator.
NO LOAD 15 • 20 VOLTS AC.
2. Short or open in the AC
wiring to the voltage regulator.
LOW AC VOLTAGE OUTPUT AT 1. Reset voltage potentiometer. 4. Faulty voltage regulator.
NO LOAD 60 -100 VAC.
2. Shorted diodes in exciter
rotor 1 to 3 diodes.
5. Short in exciter stator windings.
3. Shorted exciter rotor winding. 6. Short in rotating field winding.
HIGH AC OUTPUT VOLTAGE
1. Reset voltage potentiometer.
150 VAC OR HIGHER.
2. Faulty voltage regulator.
UNSTABLE VOLTAGE OUTPUT. 1. The potentiometer on the
2. Faulty voltage regulator.
(ENGINE SPEED STEADY)
voltage regulator needs
adjusting.
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.
VERY LOW AC OUTPUT
1. Loss of residual magnetism.
VOLTAGE 4 - 10 VAC
NOTE: AC GENERATOR TROUBLESHOOTING MUST
BE PERFORMED WITH THE ENGINE OPERATING AT 60 HZ
~ WESTERBEKE
Engines
&
Generelore
54