Electrical Wiring Repair - TM-5-4120-393-140124

TM 5-4120-393-14

4-34.

Electrical Wiring Repair

This task covers:

a. Repair

Initial setup.

Tools:

Tool kit, service, refrigeration unit NSN 5180-00-596-1474

Personnel:

Material:

Solder (Appendix E, item 3)

Equipment condition:

Turn unit power off at power source. If there is a chance that it will be turned on, also disconnect power cable to air

conditioner.

General Safety Instructions:

WARNING

Disconnect input power to the air conditioner before performing any internal

maintenance. Voltages used can KILL. Shutting the unit off at the control panel

does not disconnect unit power.

REPAIR

General . Preferred repair methods consist of replacing wires, terminals, connectors, etc., rather than splicing wires,

bending ends to form terminals, and other makeshift procedures. Although the latter may be appropriate for

emergency field repairs. Determine the proper size and length of wire, or the terminal, or connector to be used for

replacement by referring to table 4-3, "Wire List", and to the wiring diagram (see para 4-13).

Soldering Connections. Wire connections must be made mechanically sound before they are soldered. Solder

alone does not provide sufficient strength to prevent breakage. Joining surfaces of connections to be soldered must

be clean and bright. If a separate flux is used, it should conform to Specification MIL-F-14256 rosin base flux, item

16, Appendix E and should be brushed onto the joint before soldering. If a flux-core solder is used it should be

rosin core electrical solder. If uncored solder is used it should be lead-tin solder, item 3, Appendix E, conforming to

specification QQ-S-571. Wires should always be heated to the point at which the solder will melt completely and

flow into all parts of the joint. Excessive build up of solder "gobs" on the joint should be avoided or removed.

Insulating Joints. The preferred method of insulating electrical joints is by the use of heat-shrink tubing. To apply,

cut a piece of heat-shrink tubing of suitable diameter to a one inch length for covering joints at terminals or

connectors, or to a length about 1/2 inch (1.3cm) longer than the joint to be insulated, and slide the tubing over the

wire before making the joint. After the joint is made, slide the tubing so that it covers the joint, and shrink in place

with moderate heat.

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