3-24. POWER CONTACTOR (cont)
CLEANING, INSPECTION, AND REPAIR (cont)
15. Inspect and repair components as follows:
Arc chute (4). Inspect arc chute and replace plates that are broken or burned three/fourths through. Replace if
burned close to the screws.
b. Contact tips (12) and (17).
Inspect tips and replace if worn down 3/32 inch (2.38 mm). Replace silver tips if silver is worn through.
Do not use sandpaper or emery cloth.
(2) Use a file and smooth tips that are slightly corroded or pitted. Do not bend contact. Ma
intain the same
c. Contact lever (38).
(1) Inspect the bushings. If the inside diameter
is worn beyond 0.32 inch (8.12 mm), replace
(2) Inspect the hinge pin. Replace the pin if
scored or burned.
Shunt (18). Inspect the braided copper for wear,
fraying, discoloration, or stiffness. Replace the
shunt if any of the above conditions exist.
e. Operating coil (55).
(1) Use a multimeter and check coil resistance.
Replace the coil if the measured value is not
between 24.3 and 29.8 ohms.
Check the coil terminals for damage.
(3) Check the coil for damaged, dry, or brittle
insulation. If necessary, insulate by applying
electrical insulating varnish. Replace coil if