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IR-904 Extended Life - User Guide
Page 10
Appendix A - PIR Best Practices
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Appendix A:
PIR Best Practices
Introduction:
The ideal positioning of the IR-904 should optimize target detection and minimize
or eliminate false alarms. The most critical aspect of this is the background of the
IR-904 field of view. The angle at which the IR-904 faces the target path also has
an effect on the detection of the target. The minimum and maximum detection
distances should also be considered when positioning the IR-904. Lastly, the IR-
904 should always be mounted to a solid object that does not move in the wind, or
move in any other circumstances, as this could cause a false activation.
Backgrounds:
The perfect background for the IR-904 field of view is open air. Open air would
require the IR-904 to be positioned perpendicularly to the ground, or angled up
away from the ground, with no solid objects in the field of view. The next best
background for the IR-904 field of view is solid ground. Solid ground would require
the IR-904 to be angled down to the ground with no solid objects in the field of
view. Lastly, the IR-904 can be aimed at solid walls or flat surfaces, but it is
important to note that the two beams should be hitting the same material type.
(Example: If one beam was hitting a metal barn door, while the other beam was
hitting the wood siding of the barn, the different temperature changes of these two
different
materials could create a false alarm.) If either of the beams are near
sources of heat or cool air, it could create a false alarm. (Example: Outdoor
heating and cooling units.)
