Hobart 60PL20 Operation And Maintenance Manual page 94

OM-2053
TROUBLE, SYMPTOM
AND CONDITION
LOAD CONTACTOR OPERATING CIRCUIT (Continued)
2. Load contactor (K1)
will close when
control switch (20,
Fig. 1) is held in momentary
ON position. Opens immediately
when switch is released to center
ON position.
3. Load contactor
opens during power
delivery. NO fault
indicating lights on.
3-1
Page 16
PROBABLE CAUSE
A. 28.5-V DC is not
reaching plug inter-
lock relay (K2) from
aircraft for the
following reasons:
(1) Generator to air-
craft cable con-
nector defective
or not plugged
into aircraft
receptacle connector.
(2) Aircraft reject-
ing power
B. "Blown" protective
relay fuse (F2)
(1-1; 8, Fig. 6)
C. Defective plug-
interlock relay (K2)
D. Small contacts in
load contactor (K1)
defective
E. Defective fuse-
interlock relay (K17)
or resistor (R46)
A. Fuse (F1 or F2)
blown.
TEST, CHECK, AND/OR
REMEDY
A. Proceed as follows to find
the cause of this mal-
function.
(1) Inspect cable connector
plug thoroughly for dam-
aged E and F terminals.
Be sure the plug is fully mated
with the aircraft receptacle con-
nector and making good contact.
(2) Check aircraft on board
electrical equipment and
controls
B. Press the lens housing of
fault indicating lights. If lamps
do not glow, replace fuse (F2).
C. Place test-bank switch (S2)
(34, Fig. 1) in ON position. If load
contactor will now remain closed,
replace the plug-interlock relay
(K2) (Sect. 1-1; 2, Fig. 7)
D. Connect a jumper lead be-
tween small terminal no. 1
and no. 2 on the load contactor.
If load contactor will now remain
closed, replace the complete load
contactor (K1).
E. Connect a jumper across
resistor R46) (Sect. 1-1;
21, Fig. 8). If the contactor
will now remain closed,
replace the resistor (R46). If
the contactor will not rwmain
closed, replace fuse-interlock
relay (K17) (Sect. 1-1; 8, Fig. 7).
A. Remove and inspect fuses
(1-1; 8 and 9, Fig. 6).
Replace as required.
December 31/91 Revised