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ADPRO Passive-Infrared (PIR) PRO Series by Xtralis
Planning and Commissioning Manual
detect a barrier’s being driven through, precisely because of too high a speed. But
since the invader has to come to a standstill to accomplish his purpose, the system
can be planned so that this type of attack, and in particular subsequent passage
through the monitored area, can, again, be safely detected. Here, too, the right choice
of detector, and the number and strategic placement of the detectors, is especially
important.
5.2
Planning – Key Points
5.2.1
Nature (Grass, Trees, Animals)
In planning perimeter monitoring with ADPRO detectors, take note of the following points:
The area to be covered should have no moveable objects such as trees, branches,
shrubs, lawns with long grass, fences or bodies of water.
When you inspect the property, look out for animal holes such as foxholes, badgers’
setts, rabbit warrens, etc., in the vicinity of the barrier. Ask the user of the property
about this.
5.2.2
Traffic (Vehicles, Equipment, Persons)
It must be noted here that the nominal range stated is such that a person or object of height
1.5 m can be detected. This necessarily means monitoring of more than the area to be
covered, so long as it is not artificially limited.
Do not set up one single detector on a wire or metal fence, and especially not beyond
a fence.
In order to avoid false alarms caused by passers-by, the range of coverage should be
limited by a natural or artificial background (such as a wall).
Vehicles, in particular large ones that produce a lot of heat (lorries, tractors,
harvesters, etc.) and other equipment (diesel generators for power systems,
refrigerated containers, etc.) are strong sources of heat. Take care in planning that
such sources of heat are not operating in the range of a detector. If there is a car park
outside the fence, make the operator aware of it. If this is unavoidable, several
connected detectors should be used.
5.2.3
Climatic Conditions (Sun, Wind, Storms, Rain, Hail, Fog)
Depending on the climatic condition, the perimeter monitoring system is, in part, permanently
exposed to extreme environmental conditions. Because of technology PIR detectors can
sometimes perform badly. These natural factors are unavoidable, but with precise planning,
they can be to a large extent compensated for, or even eliminated entirely.
The following points should be noted:
PIR detectors are to be configured so that they are not exposed to heat radiation,
especially that of the sun. Note that the sun can be very low at some seasons.
ADPRO PRO detectors, thanks to a very complex signalling process and subsequent
validation check, offer a modern compensation system. Nevertheless, if a detector
directly faces the rising or setting sun, nuisance alarms can be triggered.
Do not set up a single detector directly on a wire fence, as in a sunny environment this
can cause significant movement in the warm air currents above the barrier.
Check whether prolonged and intense fog is to be expected at the planned site.
Because fog consists of tiny droplets of water in the micrometre range (20-40 µm), the
radiation emitted by a body might only be received dampened by a PIR detector, since
the infrared radiation is reflected and partially absorbed by the droplets of water.
Experience has shown that the distance between individual detectors should be no
greater than 45-50 metres. This makes safe operation with a good detection rate
possible.
