TM 9-4110-256-14
4-24. MOTOR STARTER K1 TESTING. REPAIR. AND REPLACEMENT.
This task covers:
a.
Testing
b.
Repair
c.
Removal
d. Installation
INITIAL SETUP
Equipment Conditions:
Materials/Parts:
Refrigeration unit shut down (para 2-7) and power
disconnected.
Lock Washers (2) (Control Box Cover)
1, Appendix G
Control panel cover open.
Lock Washers (2) (Motor Starter)
1, Appendix G
General Safety Instructions:
Marker tags (11)
7, Appendix E
WARNING
High voltage and exposed rotating parts are used in the
refrigeration unit. Personal injury can result if power is
connected.
a. Testing. (See Figure 1-4.)
(1)
Be sure power has been disconnected at the source and remove two bolts (1) and lock washers (2). Open
control box cover (3). Discard lock washers.
(2)
Press and hold plunger (4).
(3)
Using multimeter set to measure continuity, check each motor starter (5) contact continuity between
terminals L1 to T1, L2 to T2, and L3 to T3. Continuity should be indicated.
(4)
Release plunger (4).
(5)
If no continuity was indicated, test thermal overload heaters (6) per following step.
(6)
Using multimeter set to measure continuity, check each thermal overload heater (6) continuity between
mounting screws. Continuity should be indicated. If no continuity was indicated, replace thermal
overload heater (6) to repair motor starter (5) and repeat tests.
(7)
Using multimeter set to measure continuity, check coil continuity between terminals Al to A2. Continuity
should be indicated. If no continuity was indicated, replace motor starter (5).
(8)
Press and release RESET button (7).
(9)
Using multimeter set to measure continuity, check overload contacts between terminals 95 to 96.
Continuity should be indicated. If no continuity was indicated, replace motor starter (5).
(10) Using multimeter set to measure continuity, check each motor starter (5) contact continuity between
terminals L1 to T1, L2 to T2, and L3 to T3. No continuity should be indicated. If continuity was indicated,
replace motor starter.
(11) If no failure was indicated, close control box cover (3) and install two new lock washers (2) and bolts (1).
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