TM 9-4120-408-14
4-17. CONDENSER ELECTRICAL LEAD AND DIODE ASSEMBLIES MAINTENANCE. (Continued)
NOTE
For repair of diode assembly refer to Appendix F, Figure F-4.
d. Repair. Refer to Appendix F, Figure F-3 and repair damaged or defective electrical lead assembly (1).
CAUTION
Refer to tags and observe polarity, noted during removal, when installing diode assembly. Failure to
observe polarity may result in damage to equipment.
e. Install.
(1) Install electrical lead assembly (1) and secure with two flat washers (4), lock washers (3), and nuts (2).
Secure electrical lead assembly (1) with new tiedown straps approximately every three inches, as required.
Remove and discard tags.
(2) Follow on maintenance: refer to paragraph 4-11 and install side panel.
4-18. 50 AMP RELAY MAINTENANCE.
This task covers:
Test
Install
Remove
INITIAL SETUP:
Tools
Equipment Conditions
Tool Kit, Service Refrigeration Unit,
Side Panel removed, paragraph 4-11.
General Safety Instructions
Material/Parts
Do not work on equipment without
Tags, Appendix E, Item 27
following standard shop safety
procedures.
Lock Washers, Appendix G, Item 14
Ensure that power has been disconnected
Refer to TM 9-4120-408-24P for part
before performing maintenance on
numbers of items to be replaced.
electrical components.
a. Test.
(1) With air conditioner operating in HIGH COOL mode, paragraph 2-5, measure voltage across wire terminals
X1 (Figure 4-12, 1) and X2 (2) and Al (3) and A2 (4) of relay K3 (5) for 28vdc. If either measurement is
0vdc, replace relay K3.
(2) When left condenser fan assembly is operating measure voltage across wire terminals X1 and X2 and A1
and A2 of relay K1 for 28vdc. If either measurement is 0vdc, replace relay K1.
(3) When right condenser fan assembly is operating measure voltage across wire terminals X1 and X2 and A1
and A2 of relay K2 for 28vdc. If either measurement is 0vdc, replace relay K2.
b. Remove.
(1) Shut down air conditioner.
4-26
