Passive Infrared0 pages

Passive Infrared Motion Detectors
Functional principles
Passive Infrared Sensors PIR function in a
similar way to infrared cameras which are
used, for example, in familiar applications
such as detecting heat loss from buildings.
The infrared-sensitive sensor forms a heat
image of the defined area to be monitored
using a multiple-lens system (Fresnel lenses).
After an initial transient of approximately
20 sec., the measured infrared image is
saved.
The sensor switches if the heat image changes as a result of movement. Two conditions
must be fulfilled here:
1.

There must be a temperature difference
of +/– 2° C between the object to be detected and the background and

2. the object to be detected must move at
a rate of at least 10 cm/s.

Ideal temperature source

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Extremely long processes such as the rise in
temperature as a result of exposure to sunlight, the heating up of radiators, changes in
weather conditions brought about by clouds
are not detected.

Detecting people and objects
For reasons of a physical nature, PIR technolgy should only be used to detect living
things as it is not always possible to guarantee that the difference in temperature between shopping trolleys, vehicles etc. and the
surrounding environment will be great
enough. These objects may, therefore, in certain cases not be detected.
We recommend our Radar Motion Detectors
for detecting both people and objects such as
shopping trolleys and vehicles.

Possible temperature source

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The Reglomat built-in units PIR 20, PIR 30
and PIR Master are equipped with 12 (PIR 20)
or 18 Fresnel lenses. These enable the detection area to be set very accurately by means
of an internal mechanical system or diaphragms and zoom technique (patent pending). Precise and custom-built – just like
an invisible contact carpet.

Beam geometry
Important: when the object penetrates the
beams, it must be detected by at least one of
them.

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Ideal for detecting people
There is always a difference of at least 10° C
between the surface temperature of a
clothed person and the surrounding environment.

All types of installation possible
Intelligent and
temperature-compensated
Reglomat PIR operate with common-mode
rejection which guarantees dynamic response.
New: an integrated temperature sensor
optimises the control loop of the amplifier as
a function of the ambient temperature.

Our product range also includes PIR devices
for building services managment systems.
Ask for our “Special package for electricians” documentation for 220 V devices with
photo-electric lighting controllers, gong
controllers and intruder detection systems.

Typical applications
Door/gate
Small, powerful and reasonably-priced
opening pulse detectors for all systems
which open automatically. Particularly suitable for integrated installation.
Elevators
For monitoring the area in front of the elevator and whether or not the elevator is occupied.

High-precision Reglomat lenses

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Additional PIR devices

Close collaboration with our customers has
always been one of our top priorities. This is
why all PIR and Radar Motion Detectors
have identical mounting brackets, mounting
boxes for ceiling installation and protection
class IP 65 as well as machting weather
shields for installation outdoors or to provide
protection against vandalism. All of these
enable problem-free handling and considerably simplify the logistics of the detectors.

Train/bus/trolley-bus
For monitoring the entire boarding area of
vehicles with doors that close automatically.
Building services management systems
Special sensors which are used as presence
detectors for lighting, air conditioning, heating, telephone booths, small conference
rooms and cashpoint areas etc.
Sensors for open entrances, gong, call,
video. The area in front of the entrace is monitored – entry is not possible without the
gong sounding.