of relay A10K2 in the following manner: From S3 pin 2-3
functions are discussed in the following paragraphs.
through diode CR2, S5-4, S5-5, and to J10-L. If the operating
mode switch is at ACCESS, unregulated 27.5 volts dc is
c. Instantaneous Alarm Output. When a tamper alarm signal
applied to the coil of relay A10K2 from connector pin J8-17,
is received, instantaneous alarm module A9 immediately
through diode CR1, switch S5 pin 4 to 5, and to connector pin
provides an alarm signal to control unit output terminal board
J10-L. Signals from the tamper alarm buss are fed through
S; and, in the test/reset operating mode an internal buzzer is
audible alarm module A8 (pins JS8-11 to -8) and applied to a
sounded to alert using personnel of receipt of an alarm. Each
silicon controlled rectifier switch through connector pin J10-7
of these functions are discussed in the following paragraphs.
for control of relay A10K2. A no-alarm input signal (0 volts) at
connector pin J10-7 has no affect on the SCR switch circuit,
(1) Instantaneous Alarm. Signals from the tamper
therefore relay A10K2 remains in the restored position. In this
alarm buss are applied to a 10-second instantaneous alarm
condition a low impedance of 0 to 2000 ohms exists between
timing circuit on module A9 via J910. The contacts of relay
output connector pins J10-9 and -10. This no-alarm signal is
A9K1 are in the position shown in figure 6-1 for a no-alarm (0
fed to latched alarm output terminals S1-D and -DR. From
volts) input. In this condition a low impedance of 0 to 2000
J10-9 the signal is routed through the normally closed
ohms exists between output connector pins J9-14 and -U.
contacts of relays A9K1, A10K4, A9K2, and A9K3 before
This no-alarm signal is routed from J9-14 to J10-14 through
being applied to terminal S1-D. A tamper alarm signal (20
the normally closed contacts of relay A10K4, and out J10-12.
volts dc) applied to connector pin J10-7 causes the SCR
A tamper alarm signal (20 volts dc) input activates the 10-
switch to turn on and relay A10K2 to operate. With relay
second instantaneous alarm circuit. When activated the one-
A10K2 operated, an impedance greater than 100,000 ohms
shot timing circuit provides a return path to the ground buss
exists between output connector pins J10-9 and -10. This
for the 20 volts dc applied to the coil of relay A9K1 and
tamper alarm signal is applied to control unit latched alarm
causes it to operate for 10 ± 2 second. When relay A9K1 is
output terminals S1-D and -DR concurrent with the
operated, a high impedance tamper alarm signal of greater
instantaneous alarm output. The latched alarm output signal
than 100,000 ohms is present between connector pins J9-14
will remain until relay A10K2 is restored by turning operating
and -U. If the tamper alarm signal input is still present after
mode switch S3 to TEST/RESET then back to SECI. RE or
the 10-second time period, the instantaneous alarm output
ACCESS. If operating mode switch S3 is at TEST/RESET
signal will continue until the alarm input disappears.
when the tamper alarm is receive(l, a normal latched output
Instantaneous no-alarm/alarm signals are applied between
on terminals S1-D and -DR is inhibited. In this operating
terminals S1-I and -IR of control unit output terminal board.
mode a 10second alarm is applied to latched output terminals
Instantaneous alarms are output in all operating modes:
S1-I) and -DR to replace the normal latched output. From pin
secure, test/reset, access, latch, and non-latch.
2-2 of switch S3, 20 volts dc is fed through connector pin J9-3
and applied to the coil of relay A9K2. A 20-volt tamper alarm
(2) Sonalert. Plus 20 volts dc is applied to sonalert
input signal activates the 10-second timing circuit which
buzzer DS2 when operating mode switch S3 is in the
connects the return side of relay coil A9K2 to the ground buss.
TEST/RESET position. The buzzer dc return is connected
With relay A9K2 operated, an impedance greater than
through J8-13 to a transistor switch on audible alarm module
100,000 ohms exists between connector pins J9-B and -4.
AS. When the 10-second instantaneous alarm circuit is
This 10-second tamper alarm signal is applied to latched
activated by a tamper alarm signal as described in the
alarm output terminals S1-D and -DR concurrent with the
previous paragraph, 5 volts dc is fed through connector pin
instantaneous alarm output.
J9-R to J8-14 and applied to the transistor switch. The 5 volts
dc causes the transistor to conduct thereby switching the
(2) Non-Latched Alarm. If LATCH/NON LATCH
return side of buzzer DS2 to the ground )buss. The buzzer
switch S5 is in the NON LATCH position, 20 volts dc is not
will sound for 10 ± 2 seconds, until the tamper alarm input
applied to the coil of relay A10K2 to latch a tamper alarm
signal is removed, or until operating mode switch S3 is moved
output signal. In the non-latch operating mode, 20 volts dc
d. Latched Alarm Output. The latched alarm outputs consist
of latched or non-latched signals applied to output terminal
board S and an audible alarm output fed to terminal board L2.
These outputs and their duration are dependent upon the
position of switches S3 and S5.
(1) Latched Alarm. When a tamper alarm signal is
received, an instantaneous latched alarm output signal is
supplied by latched alarm module A10 if the control unit
operating mode switch S3 is in either the normal SECURE
position or at ACCESS and switch S5 is in the LATCH
position. In the secure mode, 20 volts dc is applied to the coil