Hobart 60CU20 Operation And Maintenance Manual With Illustrated Parts List page 115

OM-2226 / Operation and Maintenance Manual
60CU20 / Series 500062 / 400 Hz. Generator Set
Load Contactor Operating Circuit (Continued)
Trouble, Symptom, Condition
2. Load contactor closes when
the Output pushbutton
switch is held in CLOSED
position but opens
immediately when the switch
is released.
3. Load contactor opens during
power delivery. No fault
indicated.
May 2, 2013
Revision 2
Probable Cause
a. The plug interlock EF circuit on
CTL board could be defective
b. 28.5 VDC is not reaching the plug
interlock EF circuit from aircraft
for following reasons:
c. Generator-to-aircraft cable
connector defective or not
plugged into aircraft receptacle
connector
d. Aircraft rejecting power
e. Defective contacts in switch
mounted on side of contactor
a. A fault has developed in load
contactor holding circuit.
b. Cable accidentally disconnected
from aircraft
Test, Check, and/or Remedy
Place EF Bypass switch in the ON
position. If load contactor remains
closed, proceed to step b.
Proceed as follows to find the
cause of this malfunction.
Inspect cable connector plug
thoroughly for damaged E and F
terminals. Be sure plug is fully
mated with aircraft receptacle
connector and making good
contact.
Check aircraft on-board electrical
equipment and controls.
Connect a jumper lead between
terminals of the normally-open
auxiliary switch. If the contactor
now remains closed, replace the
auxiliary switch or the entire
contactor.
If load contactor cannot be closed
by operation of output pushbutton
switch, check circuit in accordance
with instructions in Trouble,
Symptom, Condition 1. If the load
contactor can be closed, but opens
as soon as power accepted switch
is released, check for trouble
under Trouble 2, above.
Reconnect cable.
Chapter 2-4
Page 15