Kato Engineering Standard AC Generator - Troubleshooting Generator Issues; Symptoms, Causes, and Remedies

Page 48
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Table 6: Troubleshooting
Symptom Cause Remedy
No Voltage Open voltage regulator, circuit breaker or
fuses
Check. Reset the circuit breaker or replace
fuses if open.
Overvoltage, undervoltage, or overload
devices tripped (when protective devices
are incorporated into the circuit)
Check for the cause of the abnormal condition.
Correct any defi ciencies. Reset devices.
Check the generator nameplate for nominal
operating values.
Open circuit in exciter fi eld Check continuity of shunt fi eld and leads
to voltage control. (Use ohmmeter or
wheatstone bridge) If open in fi eld coils,
remove exciter fi eld assembly and return
assembly to factory for repair.
Loss of residual magnetism in exciter
fi eld poles
Restore residual magnetism or fl ash fi eld. When
the voltage regulator is a model that requires
fl ashing, install an automatic fi eld fl ashing
system.
Open circuit in stator windings Check for continuity in the windings. Return the
generator to the factory for repair if open.
Malfunction of automatic voltage
regulator
See troubleshooting of voltage regulator.
Correct defi ciencies.
Short-circuited generator output leads Clear lead to restore voltage buildup.
Open in rotating rectifi ers Check rotating rectifi ers, and replace if
open.
Open in generator fi eld Check for continuity and return rotor to
factory for repair if fi eld coils are open.
Shorted or grounded surge protector Check for shorts or grounds. Replace .
Shorted or grounded rotating rectifi er Check for shorts grounds. Replace or repair.
Shorted or grounded exciter armature Check for shorts or grounds. Replace or repair.
Low voltage Shorted leads between the exciter armature
and generator fi eld
Test and repair.
Incorrect stator connections Check the connections, and reconnect
Troubleshooting Guide
(corrective maintenance)
Between regular preventive maintenance inspections, be alert for any
signs of trouble. Correct any trouble immediately. See Table 6 for
symptoms, causes and remedies.
WARNING: Problems left uncorrected
may result in injury or serious damage,
which can result in costly repairs and
downtime.