30
Simplex Multiplexer
Chapter 6 — Alarms
The Simplex system detects and responds to three types of
alarm events: mechanical alarms, recorded alarms and video
loss. A mechanical alarm event occurs when there is a contact
closure at any alarm input. A recorded alarm event occurs
when an alarm encoded field is detected during tape playback.
A video loss alarm occurs when the Simplex system detects
loss of video at an active camera input.
MECHANICAL ALARMS
The
alarms
connector provides one mechanical alarm input
for each camera input. These inputs can be connected to any
security device equipped with either a contact closure or
TTL/CMOS standard alarm output. Alarm polarity can be se-
lected as either
ACT LOW
or
ACT HI
using the
ALARM INPUT
POLARITY
toggle option in the setup menu.
Each alarm input requires two wires. One wire connects to the
desired alarm input pin. The second wire connects to the
ground screw (
gnd
)
next to the alarm connector. Refer to
Table 1 — Alarm Connector Pin Assignments
for details.
