Install guide

ARMY TM 5-6675-308-34
MARINE CORPS TM 08837A-34/2
Table 4-19. PS Testing and Troubleshooting – Continued
Malfunction
Test procedure
Normal indication
indication/corrective action
2ar.
Set REFERENCE switch to AMB TEMP
V LAMP -1 VDC
DVM indicates 0 (±0.1) VDC
Voltage out of tolerance: Replace
sequence monitor circuit card
assembly A5, then K2
2as.
2at.
2au.
2av.
2aw.
25x.
Disconnect DVM from PSTS
Press POWER SUPPLY OFF switch
Set MODE switch to +RECT LOAD
Set multimeter to AC volts. Set
FUNCTION switch to PS 115V LO, press
POWER SUPPLY ON switch and connect
multimeter to POWER SUPPLY 115V
LO and PWR RTN test jacks
Set MODE switch to -RECT LOAD
Momentarily set POWER SUPPLY FLAG
switch to RESET; then, to SET
2ay.
2az.
2ba.
2bb.
Set MODE switch to OVERLOAD
Set POWER SUPPLY FLAG switch to
RESET
Set FUNCTION switch to PS +28V
Press INITIATE switch
Multimeter indicates 100 to
130 VAC
Voltage should be same as
reading in step 2av, -1-10
volts
CHARGE/BATTERY indica-
tor lights when set. PS
BATT FAIL and PS FAIL
fault indicators DS 1 and
DS2 reset to black and then
set to white
PS BATT FAIL and PS FAIL
fault indicators DS1 and
DS2 to black
PS ON indicator goes off
PS FAIL fault indicator
DS2 goes to white
2bc.
Press POWER SUPPLY ON switch PS ON indicator lights
Voltage out of tolerance: Replace
power inverter assembly A6
Same as 2av
If either fault indicator fails to
activate, disc onnect PS, remove
sequence monitor circuit card
assembly A5, apply 24 VDC between
chassis (-) X45- I 2. Then a momen-
tary ground to A5J2-23 or A5J12-24
should activate the indicator. A
ground to 3J5-12 should clear both
indicators. If this doesn’t work, check
for broken wires; if no broken wires
are found, DS 1 and/or DS2 are faulty
and should be replaced. Reinstall
sequence monitor circuit card
assembly A5
OVERLOAD FAIL indicator lights:
Replace sequence monitor circuit card
assembly A5, then 28V converter-
regulator circuit card assembly A3,
then +20V converter-regulator circuit
card assembly A2, if required
4-115