Xtralis ADPRO Presidium, Installation And User Manual

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ADPRO Presidium by Xtralis Installation and User Manual
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Camera/PIR Alignment
The camera alignment relative to the boundary and other cameras is paramount in ensuring that
there are no 'blind-spots' on the site. Align each camera to cover the dead zone of the next
camera, and to adequately cover the area under protection. If, due to practical limitations,
external areas not requiring detection are included in the camera view, use the detection area
selection feature in Presidium configuration to mask out such areas. The following figure shows
camera alignment and PIR alignment around the perimeter of a facility.
Figure 15: Camera/PIR Alignment
Illumination Requirements
Ideally, the illumination around the site should be even, with no major contrast changes caused
by shadows at all times of the day and night. Typically, to provide more even illumination, it is
better to utilise high levels of ambient lighting throughout the field of view of the camera rather
than subjective lighting systems. To ensure continuous monitoring by Presidium, the lighting (or
illuminators) should be on at all times during hours of darkness (typically photo-cell controlled).
Switching illuminators on at the point of alarm in order to deter intruders is not effective because
if illumination levels are too low, Presidium may not detect the intrusion. If the scene contrast is
poor, and no additional lighting can be installed, then the contrast can be increased by adding
stripes to walls and pathways, by painting the background surfaces a light colour or by laying
strips of different colours of gravel.
Determining the required lux level from a mathematical calculation can be difficult. There are
references available that describe this process in detail. Refer to these references, or other
sources for a mathematical approach in determining the lux level required at a site to provide
adequate illumination for the cameras selected. Lux meters are available for checking the
illumination level at a site and to relate the measurements to camera specifications. A good rule
of thumb is, if the target is clearly visible to the human eye at the maximum range under the worst
lighting conditions, then a camera can detect it.