TM 9-4120-407-14
3-19. ELECTRICAL WIRING REPAIR - GENERAL.
Repair
This task covers:
INITIAL SETUP
Tools
Materials/Parts
Service Refrigeration Unit Tool Kit
Wire (As Required)
Insulation Sleeving (Heat Shrink Tubing)
Equipment Conditions.
Power disconnected at source.
Repair.
Solder and flux contain materials which are hazardous to health.
Avoid breathing vapors or fumes from soldering operations. Perform
operations only in well-ventilated areas. Wash hands with soap
and water after handling solder and flux. Wear thermal gloves and
protective goggles or face shield to protect against burns.
(1) 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. Flux should be brushed onto the joint before soldering.
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.
(2) 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 length of 1 inch (2.5 cm) for
covering joints at terminals or connectors, or to a length about 1/2 inch (1.3 cm) longer than the joint to be
insulated. 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.
(3) Splicing Wires. To repair broken or cut wires that are otherwise sound, the mating ends can be
stripped and spliced. Solder and apply insulation as described above.
(4) Crimping Terminals. To install a terminal on the end of a wire, strip 1/4 -1/2 inch (0.6-1.3 cm) of
insulation from the end of the wire and apply a one-inch (2.5 cm) piece of heat-shrink tubing
(if the terminals are of the uninsulated type). Insert wire-end into the shank of the terminal. Crimp the
shank and install heat-shrink tubing, if necessary.
NOTE
Preferred repair methods consist of replacing wires, terminals,
connectors, etc., rather than splicing wires, bending ends to form
terminals, and other make-shift procedures, although the latter may
be appropriate for emergency field repairs.
(5) Determine the proper size and length of wire, or the terminal, or connector to be used for
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