(59) and spacer (60) tagging leads before removing
terminal board (64), Remove terminal nut (61), nut
(62), and screw (63). Install in reverse order of re-
moval. Diodes are tested and replaced at a higher
level of maintenance.
4 - 4 7 .
T h e r m o s t a t
S w i t c h .
a. Inspection. Remove cover ( 1 6 , f i g . 4 - 1 4 ) and
ins~ect thermostat switch (85) for loose mounting and
wiring connections. Test for proper operation.
b.
Testing.
(1) See f i g u r e s 4 - 1 3 , 4 - 1 4 , a n d 4 - 1 6 and re-
move switch in accordance with p a r a g r a p h c . below.
(2) Fill suitable container with clean oil having
a flash point above 600°F.
(3) Suspend thermostat switch in container of
oil. Aiso, suspend a thermometer in container of oil.
(4) Connect multimeter between switch terminals.
WARNING
Ensure oil in container has a flash point
exceeding 600° F, oil is heated gradually,
and necessary fire precautions are taken.
(5) Heat container of oil gradually, and stir so
heat is evenly distributed.
(6) Observe multimeter and thermometer for
indication of infinity (open switch) below 4500F +
150F. At 4500F + 150F, multimeter shall indicate
continuity (switch closed).
(7) Permit oil to cool, multimeter shall indi-
cate infinity {switch open) at 351°F * 15°F. Replace
if defective.
c.
Replacement. To replace thermostat switch
( 8 5 , f i g . 4 -
remove nut (82), washer (83), and
screw (84) tag~ing leads before removing switch.
Install switch in reverse order of removal.
4 - 4 8 .
H e a t e r
E l e m e n t s .
wARNING
Ensure heater elements are cold and load
bank is disconnected from generator set.
a. Inspection. Remove cover ( 1 6 , f i g . 4 - 1 4 ) and
insfiect heater elements (88) for loose mounting.
loose electrical connections, cracks, breaks, cor-
rosion, and other damage.
b.
Testing,
(1)
Remove
one end of heating
elem,3nt.
nut which secures harness lead to
element and remove lead from
(2) Test heating element for continuity. If
open, replace heating element.
(3) Measure resistance between terminals. Re.
sistance should be approximately 10 ohms,
(4) Reconnect lead.
Replacement. To replace the heating elements
( 8 8 , f i g .
4 - 1 4 ) , remove nut (86) and screw (87) tag-
ging leads before removing elements. Install in re-
verse order of removal.
4 - 4 9 .
R e m o v a l .
See f i g u r e s 1 - 1 , 1 - 2 , 1 - 2 1 , 1 - 2 6 o r 1 - 2 7 , a n d 4 - 1 3 ,
and proceed as follows:
~. Refer to
p a r a g r a p h
2 - 1 3 and stop generator set.
b. Set % LOAD SELECTOR SWITCH to OFF.
c. Disconnect special purpose cable plug P50
( 6 ,
f i g .
4 - 1 4 ) from tactical relay box receptacle
J50.
d. Disconnect special purpose cable plug P51
froti cable 70-1212 plug P51.
e. Connect cable 70-1212 plug P51 to tactical
rel~y box receptacle J51.
f. Disconnect load bank four-wire power cable
(13Tfrom load terminal board terminals ( f i g . 3 - 2 4 ) .
~. Remove load bank four-wire power cable
( 1 3 ,
f i g . 4 - 1 4 ) and special purpose cable (6) from the gene-
rator set through the plate and sleeve assembly hole
( f i g . 3 - 1 5 ) .
h. Remove load bank four-wire power cable
( 1 3 ,
f i g . 4 - 1 4 ) and special purpose cable (6) from loop
clamps at rear top left side of housing. Replace screws
in housing after removal of cables and clamps.
i. Remove six screws, 12 lockwashers, and six
nut~ securing load bank to set housing and remove
load bank from housing.
4 - 4 3 / ( 4 - 4 4
b l a n k )
