TP-5867 11/02 21Section 3 Troubleshooting
Problem Possible Cause Corrective Action Reference
No generator
output voltage
Defective stator (open, grounded, or
shorted windings)
Test and/or replace. Section 6, Component
Testing and Adjustment
K1 relay (NC) contact open Check continuity. Section 4, Controller
Troubleshooting and 9,
Wiring Diagrams
Brushes sticking in holder Check springs and alignment. Section 6.6, Brushes
Rotor slip rings dirty or corroded Check and/or service. Section 6.6, Brushes
Worn brushes Replace worn brushes. Section 6.6, Brushes
Defective or misadjusted voltage
regulator
Excite (rotor) separately. Section 6, Separate
Excitation, and 6.3.1, Voltage
Regulator Test
Low engine rpm Check engine speed using a
tachometer or frequency meter.
Note: Hzx60=rpm
(Example 57 x 60 = 3420 rpm)
—
No AC output
Circuit breaker open or defective, if
equipped
Reset breaker to ON position.
Check AC voltage on generator
side of circuit breaker.
Section 1.6, Service Views,
for location
Circuit breaker tripping because of
overload on generator set
Reduce load. O/M
No battery voltage to voltage regulator
during cranking: (+) and (--) terminals
on regulator
Check for DC voltage at voltage
regulator terminals listed.
Sections 6.3, Voltage
Regulator, and 9, Wiring
Diagrams
Blown voltage regulator fuse Replace fuse; if fuse blows again,
check voltage regulator and/or
stator auxiliary windings.
Sections 6.3, Voltage
Regulator, and 9, Wiring
Diagrams
Open wiring, terminal, or pin in buildup
circuit or voltage regulator circuit
Check continuity. Sections 6.3, Voltage
Regulator, and 9, Wiring
Diagrams
Brushes sticking in brush holder or
broken brush spring
Check brush position and
condition.
Section 6.6, Brushes
Rotor slip rings dirty or corroded Check slip ring condition. Section 6.4, Main Field
(Rotor)
Defective rotor (grounded windings) Check voltage and continuity. Section 6.4, Main Field
(Rotor)
Defective stator (open, grounded, or
shorted windings)
Check voltage and continuity. Section 6.5, Stator
Defective or misadjusted voltage
regulator
Excite rotor separately and check
for AC output. Readjust voltage
regulator.
Section 6.3, Voltage
Regulator
Defective K3 relay (field flashing) in
relay controller circuit board
Test/replace relay controller circuit
board.
Section 4, Controller
Troubleshooting
To Next Page
Loading...
