TM 5-6115-640-14&P
a.
Test. To isolate the source of an electrical system problem, perform continuity tests on the components of the
switch box as described below. Refer to the schematic diagram inside the switch box (shown in figure 4-4) to locate and
identify the test points indicated in these procedures. The switch boxes, except for power cable lengths, are identical for
both the AN/MJQ-32 and the AN/MJQ-33 power plants.
(1)
Switch Test.
(a)
Remove 16 screws (1, figure 4-5), lockwashers (2), and flat washers (3) from switch box front panel
(4) and pull panel forward.
(b)
Set multimeter for continuity tests.
(c)
Set rotary switch (5) to GEN 1 position.
(d)
Touch one probe to switch terminal (6) Al and remaining probe to switch terminal L1. Repeat test
between terminals A2 and L2 and terminals A3 and L3. If multimeter does not indicate continuity
exists between each pair of terminals, switch is defective. Notify higher level of maintenance.
(e)
Set rotary switch (5) to GEN 2 position and repeat step (d) above, substituting terminals B1, B2, and
B3 for A1, A2, and A3.
(2)
Electrical Leads (Wiring Test).
(a)
Remove 16 screws (1, figure 4-5), lockwashers (2), and flat washers (3) from switch box front panel
(4) and pull panel forward.
(b)
Set multimeter for continuity tests.
(c)
Test each wire (7) between its switch terminal (6) and load (post) terminal (8) by touching probes to
each of following pair of test points: L1 on switch to load (post) terminal L1, L2 on switch to load
(post) terminal L2, and L3 on switch to load (post) terminal L3. If multimeter does not indicate
continuity between each pair of test points replace associated wiring.
(d)
Test ground wire (10) by touching one probe to load terminal (8) LO on switch box terminal board
and touch remaining probe to E2 (AC GROUND) (9) on switch box. If multimeter does not indicate
continuity, replace associated wire.
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