Table 5-1.
Troubleshooting - Audible Alarm
Unit Status
Trouble symptom
Test action
Indication
Probable cause
Corrective action
AC power on. no.
1 Battery Low (< 24 V de)
Check for 115 V ac at L1-1 and
No 115 V ac
No AC power
Reconnect AC power source.
alarm
L1-2.
Check for 115 V ac at L1-1 and
No voltage on unit side of fuse
Fuse open
Replace fuse.
L1-2.
Check for 115 V ac on side of
No voltage through switch
Defective switch
Replace switch.
power switch S3 (A).
Measure voltage at TB3-1 and
Less than 36 V ac
Defective power trans-
Replace transformer.
TB3-2
former.
Measure voltage on battery
Same low voltage on both
Defective Al PWB
Replace electronics assembly.
with no AC power applied
switch terminals, no pulses.
Measure voltage on battery
Different voltage at each ter-
Defective switch
Replace switch.
with ac power applied
minal.
Same
low voltage on both
Defective battery
Replace battery.
switch terminals, pulses.
AC Power on, alarm
2. No audible alarm
Check for 115 V ac and 25 V dc
Neither voltage appears at
Defective switch
Replace switch.
at Control Unit
on both sides of power switch
both sides of switch.
(S3)
Measure voltage at L1-3
Voltage is less than 25 v dc
Defective power supply/
Replace electronics assembly.
charger.
Measure alarm voltage at :L2-1
Voltage greater than 1 V dc
Control Unit
Refer to troubleshooting pro-
and L2-2
cedure for control unit.
Measure voltage at TB3-4
Voltage is less than 10 V rms
Defective A2 PWB
Replace electronics assembly.
Measure voltage at secondary of
Voltage less than 11 V rms
Defective output trans-
Replace output transformer.
output transformer (T2) at
Audio signal present
former
Replace speaker.
TB3-6 and TB3-7
Defective speaker.
3. Low sound level
Measure voltage at L1-3
Less than 25 V dc
Power Supply or battery
See low battery troubleshoot-
defective
ing.
Measure voltage at TB3-4
Less than 10 V rms
Defective amplifier
Replace electronics assembly.
Measure voltage at speaker ter-
Less than 17 V rms speaker
Defective output trans-
Replace output transformer.
minals
former.
17 V rms at speaker
Defective speaker
Replace speaker.
AC power on, no a-
4. Audible alarm
Measure voltage at L2-1 and
4.5 to 5.5 V dc
Defective amplifier
Replace electronics assembly.
larm at control unit
L2-2
Less than 1 V de
Hardwire line broken
Repair broken line.
AC power on, no
5.Tamper alarm output to
Measure resistance at Pl-12 and
Less than 0 ohms
Open door and pry-off
Isolate defective
tamper alarm
control unit 1 V de at
L2-2
switch
replace.
L2-3.
Measure resistance from outer
< 10K S
Enclosure shorted together
Determine origin of short,
to inner enclosures
remove.
Measure voltage at P1-12 and
<1 V dc
5volt regulator inoperative
Replace electronics assembly.
L2-2.
Measure voltage L1-3
Less than 25 V dc
No supply voltage
See battery troubleshooting.
AC power on, tamper
6. No alarm at control
Measure voltage at L2-3
< 3 V dc
Defective impedance detec-
Replace electronics assembly.
alarm-
tor.
AC power on, audible
7. Tamper alarm not indi-
Measure voltage at L2-3
< V dc
Defective impedance moni-
Replace electronics assembly.
alarm
cated at control
tor.
Change 2 5-2
