TM 11-6625-298-14
CAUTION
NOTE
Do not exceed the voltage rating of the
The ohmmeter pointer will dip toward zero
capacitor under test.
when the crank is first turned, but will
a. Connect a test lead from the GROUND
move up the scale as the capacitor becomes
terminal of the ohmmeter to the case of the
charged with the test potential. The
capacitor must be fully charged with the
b. Connect another lead from the LINE terminal
test potential before a reading may be
of the ohmmeter to one of the terminals of the
taken. To be sure that the capacitor is fully
capacitor.
c. Turn the hand generator at operating speed.
minute.
The indication obtained is the insulation between
e. Turn the crank handle at operating speed. The
insulation reading should be 500 megohms or
the capacitor and its case. The indication should be
500 megohms or more.
greater.
d. Remove the GROUND lead from the case of
the capacitor and connect it to the remaining
terminal of the capacitor.
speed. If the bushing under test is the dry type,
3-10. Insulation Test of Insulating Bushings
the reading should be INFINITY or near IN-
a. Connect a test lead from the GROUND
FINITY. If the bushing under test is the filled
terminal of the ohmmeter to the base of the
type, the reading should be near 1,000 megohms.
bushing.
d. If the reading is lower than near INFINITY
b. Connect another test lead from the LINE
for a dry-type bushing or 1,000 megohms for a
terminal of the ohmmeter to the bushing terminal.
filled-type bushing, connect the third test lead to
c. Turn the hand generator crank at
operating