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POLITEC | INSTALLATION MANUAL - VER.3.1
10.2 Introduction to barriers - IR section
The Active Infrared Barrier is characterised by two components, a TX transmitter that impulsively
emits an infrared signal, towards the RX receiver.This signal is constantly controlled by a
CODED
SYNCHRONISM
which can be WIRED
or OPTICAL
according to the different types of barriers.
The transmitted infrared beam takes on a conical shape: the greater the distance between TX and RX,
the greater the diameter of the cone when it arrives.
View from above
TX
RX
MANA DT SMA
2°
50 m
2 m
TX
Signal interruption:ALARM
A barrier can be composed of several TX transmitters and RX receivers mounted inside specific
different columns.
The infrared barriers have multiple controls that significantly limit false alarms, as the genuine
alarm signal is given by the complete interruption of the infrared signal.
HEATERS
It is recommended to power the thermostating system as, in conditions of high humidity, the
condensation that is created on the screen can lead to a significant decrease in the IR signal up to
the alarm.For obvious reasons, for battery powered barriers, there is no thermostat control even if
set up, therefore to minimise the problem, it is necessary to reduce the working distance between
TX and RX, thus ensuring a good amount of signal constantly, even in case of particular climatic
conditions.
POWER SUPPLY
The barriers can be divided into two categories, powered at low voltage and connected by wire, or
powered by batteries for wireless systems, then combined with radio transmitters to communicate
with the alarm control unit, as required by specific sector regulations.
