Biddle MEGGER - Page 4

FIGURE 1. The “Major” Megger hand-cranked insulation tester. The
crank should be turned with a combined arm and wrist motion.
5. Use well-insulated testing leads having single-conductor
stranded wire. See page 29.
6. Check testing leads. With leads connected to the instru-
ment terminals and with opposite ends separated, turn the
crank at normal speed. If the pointer indicates less than Infin-
ity, there is a leak between the leads which must be removed
before proceeding with tests. Touch together the test ends of
the leads while turning the crank, to make certain—by a Zero
reading—that the leads are not open-circuited.
7. Apparatus to be tested must not be live. It must be taken
out of service and disconnected electrically from all other equip-
ment. See Safety Precautions, page 11.
8. Connect leads to apparatus to be tested. See connection
diagrams, pages 13 to 23.
For testing to Ground—connect from the Line terminal to a
conductor of the apparatus, and from the Earth terminal to
frame of machine, sheath of cable or to a good ground.
[21