TM 11-5895-846-14
Table 8-13. Alarm Monitor, Troubleshooting Chart
Item of Check
Test Conditions
Normal Indications
Remarks
WARNING
DANGEROUS VOLTAGES EXIST IN THIS EQUIPMENT. Do not attempt any removal or replacement
unless the equipment is in a non-operating condition and all power circuit breakers on the power
distribution panel are in the OFF position.
a. Perform the procedures of para.
1.
Preliminary setup.
8, 16c, d and e.
b. Connect the P4 cable ac plug
to a 115 volt, 50-60 Hz power
source. Turn on the power source
multimeter (set for ac volts) to
115 volts approx. (test
As required, refer to figure
the 115 V ac HI and LO test
bench power source may
points. Observe the multimeter
vary from this indication).
schematic.
and then remove it.
c. Place ac power (ac PWR) switch
Line is ON.
to the ON position. Press circuit
breaker CB1 to close it. Ob-
serve power indicator line.
d. On the alarm monitor (UUT) place
POWER/AC indicator is
If no indication, check
POWER circuit breaker (CB1) to
ON. (On the test
unit wiring between J1,
the ON position.
fixture, DS7 and DS8
CB1, and DS1. See figure
are on.)
a. On the test fixture connect the
2.
Power wiring.
P3-W: + 24 V
If no indication check
multimeter (set for dc volts)
P3-Y: + 5 V
unit wiring at the ap-
across the indicator de
P3-N: + 5 V
propriate pins on J3. See figure
test point of P3 and any one of
P3-F: + 15 V
the following ground test points
P3-G: - 15 V
of P3: H, X, C, E. Change
the ground test point with each
measurement.
NOTE
Reverse the polarity of
the multimeter test leads for
the - 15 V measurement.
b. On the test fixture connect the
P2-D: + 5 V
If no indication check
multimeter (set for dc volts)
unit wiring at the ap-
across the indicated dc
propriate pins on J2.
test point of P2 and each of
See figure FO-20.
these ground test points: P2-A,
D, E. Observe the multimeter
for an approximate indication.
c. On the UUT connect the multi-
XA1-1: +5 V
If no indication, check
meter (set for DC volts) to
unit wiring from XA1-1
XA1-1 (+) and XA1-2 (ground).
to unit connector P2 and
Observe the multimeter for an
from XA1-2 to ground.
approximate indication.
See figure FO-20.
d. On the UUT connect the
XA1-47: + 5 V
If no indication check as
multimeter to XA1-46 (ground)
XA1-27: + 15 V
above but of the asso-
and the XA1 pins as listed in the
XA1-23: - 15 V
ciated wiring. See figure
Normal Indication column.
Observe polarity.
a. On the UUT, place unit FAULT
3.
Audible alarm LS1.
Pulsating tone.
See figure FO-20. If the tone is
switch S1 to the TEST position
not heard proceed to step
b. If tone is heard pro-
and return to the indications.
ceed to step e.
b. On the UUT, connect the
+ 15 V approx.
See figure FO-20. If no indica-
multimeter (set for DC volts)
tion check wiring from
to the (+) terminal of LS1 and
LS1 (+) terminal to
ground (fig. 8-7). Observe
chassis connector P2.
the multimeter.
If indication is normal
proceed to step c.
8-37
