ARMY TM 9-6115-464-12
AIR FORCE TO 35C2-3-445-1
NAVY NAVFAC P-8-624-12
Connect an ohmmeter across two outer terminals of rheostat. Indication shall be 250 ohms resis-
Rotate rheostat shaft counterclockwise as far as it will go.
Connect ohmmeter between center terminal and either outer terminal.
Slowly, at an even rate, rotate rheostat shaft clockwise as far as it will go while observing the
Ohmmeter indication shall increase, at an even rate, from 0 to 250 ohms resistance.
If ohmmeter indication changes erratically, or is not 250 ohms when rotation is complete, the
rheostat is defective and shall be replaced.
(a) Install rheostat (69, Figure 4-38, sheet 2 of 3) and nut (68).
(b) Install control knob (67) on rheostat shaft and secure with setscrew.
(c) Connect electrical leads to voltage adjust rheostat.
Battle Short Switch.
(a) Tag and disconnect electrical leads to battle short switch.
(b) Remove nut (70, Figure 4-38, sheet 2 of 3) and tooth lockwasher (71) to remove switch
guard (72), battle short switch (73) and key washer (74).
(c) Do not remove nut (75) unless inspection reveals damage and replacement is necessary.
(2) Cleaning and Inspection.
(a) Clean switch and switch guard with filtered compressed air and a soft bristle brush or wipe with
a clean, lint-free cloth lightly moistened with an approved cleaning solvent.
(b) Visually inspect switch for cracked casing, corrosion, stripped or otherwise damaged threads,
and evidence of shorting or damage.
(c) Check switch guard for cracks, breaks, and other damage.
Place switch in ON position (lever away from switch mounting bushing key way).
Using an ohmmeter, check for continued between each center terminal and the corresponding upper
Place switch in OFF position.
Check for continuity between each center terminal and corresponding lower terminal.
Replace switch if any discontinuity is noted.
If removed, install nut (75, Figure 4-38, sheet 2 of 3).
Install key washer (74), battle short switch (73), switch guard (72), tooth lockwasher (71), and
Connect electrical leads to battle short switch.