Operation Manual – ITW GSE 6400 Tier 3
Protective Circuit
NOTE:
Protective monitoring is not completely functional until the load contactor is CLOSED. Since it is not
advisable to vary voltages for test purposes while delivering power to an aircraft, the GPU should be
connected to a load bank for trouble shooting protective circuits.
Trouble, Symptom,
Condition
Probable Cause
Test, Check, and/or Remedy
1.
Load contactor
opens during power
delivery. Over
voltage fault
indicated.
a.
Over-voltage condition
may have been the result
of a sudden drop in load
and may have been a
normal action.
Press appropriate
Output
pushbutton and resume
power delivery. Observe voltmeter to be certain
voltage is normal (28.5 VDC). Adjust to normal if
necessary. If load contactor is opened again and
the fault message indicates an over-voltage
condition, proceed to step
b
.
b.
Defective Interface or
control board.
Replace the control and/or the interface board.
2.
Load contactor
opens during power
delivery. Under
voltage fault
indicated.
a.
Under-voltage condition
may have been result of
a sudden shock load, or
possible tampering with
REG potentiometer, and
may have been a normal
action.
Press appropriate
Output
pushbutton and resume
power delivery. Observe voltmeter to be certain
voltage is normal (28.5 VDC). Adjust to normal if
necessary. If load contactor is opened again and
the fault message indicates an under-voltage
condition, proceed to step
b
.
b.
Defective Interface or
Control board.
Replace the control and/or the interface board.
OM2254 Rev A
Page 92 of 103
