TM 9-4120-402-14
4-39. TRANSFORMER (T1).
This task covers:
a. Remove
b. Inspect
c. Test
d. Install
INITIAL SETUP
Tools
Equipment Conditions:
Refrigeration Unit Service Tool Kit
CAUTION
Use disconnect switch (NOT POWER
CABLE) to disconnect power to unit.
Damage to cable connector pins will
Heat Gun
result if cable is used
Disconnect power at power source.
Materials/Parts
Transformer
Lock Washers (8)
Insulation Sleeving
(Heat-Shrink Tubing)
a. Remove
(2)
Remove four screws (1), four nuts (2), eight lock washers (3), and four flat washers (4).
Pull
transformer (5) from unit.
b. Inspect.
Check transformer (5) for signs of damage or overheating. Replace if damaged.
c. Test.
(1) Check for continuity across the primary winding pin 1 to pin 2 and across the secondary winding pin 3 to pin
4. If either winding is open, replace transformer.
(2) Check for shorts between one terminal of each winding and transformer case and also between one primary
setting. Replace transformer if a short is indicated.
(3) Apply 208.0 volts AC +20.8 input to terminals 1 and 2. Voltage at transformer output terminals 3 and 4
should be 23.5 volts AC +0.7. Remove power from transformer. Replace if defective.
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