TM9-4110-254-14
4-21.
CIRCUIT BREAKER CB1 TESTING AND REPLACEMENT.
This task covers. a. Testing b. Removal c. Installation
INITIAL SETUP
Equipment Conditions:
General Safety Instructions:
disconnected.
WARNING
Control box cover door raised and latched.
High voltage and exposed rotating parts are
used in the refrigeration unit. Personal injury
Materials/Parts:
can result if power is connected.
Lock Washers (2)
Lock Washers (6)
Marker Tags (6)
(1)
Be sure power has been disconnected at the source and remove two bolts (1) and lock washers (2). Discard
lock washers.
(2)
Carefully pull circuit breaker cover (3) out to expose circuit breaker (4) terminals.
(3)
Using multimeter set to measure continuity, check circuit breaker (4) continuity between terminals A1 to A2, B1
to B2, and C1 to C2 with circuit breaker in both ON and OFF position. Continuity should be indicated only
when circuit breaker (4) is in the ON position. If continuity was indicated in the OFF position or if no continuity
was indicated in the ON position, Replace circuit breaker (4)
(4)
If no failure was indicated, carefully push circuit breaker cover (3) into place and install two new lock washers
(2) and bolts (1).
b. Removal.
(1)
Be sure power has been disconnected at the source and remove two bolts (1) and lock washers (2). Discard
lock washers.
(2)
Remove six screws (5), lock washers (6), and circuit breaker cover (3). Discard lock washers.
(3)
Check gasket (7) material for damage. If damaged, notify direct support maintenance to replace it.
NOTE
Terminal hardware is supplied with circuit breaker.
(4)
Tag wire lead terminals (8) and remove six nuts (9), lock washers (10), and wire lead terminals.
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