TM
5-3431-200-15
Section VII. ELECTRICAL SYSTEM
50. General
This section contains maintenance instruc-
tions for the electrical components of the weld-
ing gun and control assemblies. Figures 3 and
19 respectively, are the practical and schematic
wiring diagrams of the welding set electrical
system.
Warning: Disconnect source of power from
welding set before performing any electrical
maintenance.
51. Cable Assemblies, Grip, Strain Reliefs,
Power Switch, and Terminal Strip
the cable assemblies, grip, strain reliefs, power
switch, and terminal strip.
b. Cleaning and Inspection.
(1) Clean all parts with a dry, lint-free
cloth or with dry compressed air,
(2) Inspect the cable assemblies, grip, and
strain reliefs for cracks, breaks, and
power
deterioration. Inspect the
switch and terminal strip for security
of mounting and for worn or stripped
threads on terminal screws. Replace
damaged and defective parts,
stall the cable assemblies, grip, strain reliefs,
power switch, and terminal strip.
d. Field Expedient Repair. If the power
switch is defective remove the switch, tape the
leads together, and operate the welding set
without the switch until replacement can be
made.
Warning: While the power switch leads are
Figure 12. Cable assemblies, grip, strain reliefs, power
taped together, the welding set cannot be
switch , and terminal strip, removal and installation
turned off, except by disconnecting the outside
b. Cleaning and Inspection.
power source. Do not attempt maintenance on
the electrical system while the set is operating
(1) Clean the welding wire feed control
under field expedient repair conditions with-
rheostat, rheostat resistor, and fuse
out disconnecting the power source.
holders with a dry, lint-free cloth.
(2) Inspect for cracks, breaks, security of
52. Welding Wire Feed Control Rheostat,
mounting, and improper operation.
Rheostat Resistor, and Fuse Holders
Replace damaged and defective parts.
c. Welding Wire Feed Control Rheostat
Testing. Test the rheostat by performing the
the welding wire feed control rheostat, rheo-
following steps:
stat resistor, and fuse holders.
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