TM 9-4110-256-14
4-33.
POWER DISTRIBUTION BLOCK TB2 TESTING AND REPLACEMENT.
This task covers: a. Testing
b. Removal
c. Installation
INITIAL SETUP
General Safety Instructions:
Equipment Conditions:
Refrigeration unit shut down (para 2-7) and power
disconnected.
WARNING
Right side condenser door open.
Enclosure assembly door open.
High voltage and exposed rotating parts are used in the
refrigeration unit. Personal injury can result if power is
Materials/Parts:
connected.
Lock Washers (4)
13, Appendix G
Self Locking Nuts (4)
14, Appendix G
Marker tags (9)
7, Appendix E
a. Testing. Be sure power has been disconnected at the source, then using multimeter set to measure continuity,
check power distribution block (1) continuity between each terminal A, B, C, and N to ground. No continuity should
be indicated. If continuity was indicated, replace distribution block.
b. Removal.
NOTE
Ground wire terminal hardware is supplied with enclosure assembly.
(1) Be sure power has been disconnected at the source then tag and disconnect wire leads (2). Remove bolt (3),
lock washer (4), and wire leads.
(2) If enclosure assembly (5) must be replaced, pull wire leads (2) out through strain relief cable bushings (6).
(3) Remove two conduit lock nuts (7) and strain relief cable bushings (6)..
(4) Remove four bolts (8), lock washers (9), and flat washers (10).
(5) Remove four self locking nuts (11), screws (12), and power distribution block (1). Discard self locking nuts.
c. Installation.
(1) Install power distribution block (1), four screws (12), and new self locking nuts (11).
(2) If enclosure assembly (5) was removed, install enclosure assembly, four flat washers (10), new lock washers (9),
and bolts (8).
(3) Install two strain relief cable bushings (6) and conduit lock nuts (7).
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