TM 55-2210-224-34
3-22. FIELD SHUNT CONTACTOR (cont)
ADJUSTMENT (cont)
c. If the tip break is not correct, check for the following conditions:
(1)
Worn or bent contact tip
(2)
Bent armature stop
(3)
Worn or bent contact lever
d. Adjust gap by bending the armature stop.
30. Measure tip alinement and adjust as follows:
NOTE
The maximum allowable side-to-side misalinement of the contact tips is
3/32 inch (2.88 mm).
a.
Check tip for misalinement. If necessary, loosen the screws holding the magnet frame and stationary contact-
tip support to the block and move the assembly until tips aline properly.
b. If tip misalinement cannot be corrected, check for the following conditions:
(1) Grooving or uneven wear of the armature stop.
(2) Rounded knife edge or uneven wear of the armature pivot point.
(3) Grooving or uneven wear of the armature guide.
31. Measure tip pressure as follows:
a. Measure initial pressure as follows:
(1)
Block the armature (not the tip lever) so the contacts nearly touch.
(2)
Measure the pull required to just move the contact-tip ar
m against the contact pressure spring.
(3)
Check for a pull of 2 to 4 lb (0.907 to 1.814 kg).
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