Assa Abloy PTI AP1 - Switches

USER MANUAL
Page - 14
AP1 KEYPAD
Input Switch Supervision
The AP1 has the capability to monitor the two inputs for tampering. This is accomplished
by using supervised switches. Supervised switches incorporate 1K ohm resistors
securely located inside the switch housing.
Supervision Type Diagram Description
Unsupervised
An unsupervised conguration is shown to
the left. There is no supervision resistor. In
this conguration the controller detects no
difference in a cut wire or open switch or
a shorted wire or closed switch. A switch
congured as unsupervised will not produce a
tamper event for its input as it has no means of
knowing that tampering has occurred.
Series
Supervised
A Series Supervised conguration includes a
1K ohm resistor in series with the switch. In
this conguration, a short in the wires can
be detected and tamper event produced. A
cut or open will not be seen any differently
that an open switch contact, therefore this
conguration only provides protection for
normally open switches.
Parallel
Supervised
A Parallel Supervise conguration includes
a resistor in parallel with the switch. In this
conguration, an open can be detected and
produce a tamper event. A short will not be seen
by the controller any differently than a closed
switch contact, therefore this conguration
only provides protection for normally closed
switches.
Dual Supervised
A Series / Parallel supervised conguration
includes a 1K resistor in parallel and a
1K resistor in series with the switch. This
conguration can detect both opens and shorts
in the wires which connect to the switch and
will produce tamper events as a result. This
conguration provides protection for both
normally open and normally closed switches.
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