Jung A3181-1-01, Руководство по эксплуатации

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Universal automatic switch 1.1 m
– Contrast between the heat source and the environment: if the heat source radiates just as
intensely as the environment. detection will be significantly more difficult (Figure
5
).
– Speed of movement: a faster moving object produces clearer signals in the sensor.
– Direction of movement: if detection radiation passes tangentially, this typically results in an
abrupt sensor signal which can be evaluated well. However, if a heat source moves radial
to the sensor, the sensor signal changes happen more slowly. This makes differentiation
from the background noise significantly more difficult.
– Concentration of the detection field: the number of sectors and switch segments of the de-
tection field determines the the concentration of the scan and therefore the response be-
havior.
– Sensor sensitivity: the sensor sensitivity can be adjusted according to application and en-
vironment. Low heat contrasts outdoors may require a high sensitivity that is far to high for
indoor use. The sensitivity should be decreased in this case.
– Environmental medium: high humidity or rain can negatively influence the permeability for
infrared radiation.
Figure
4
: Detection of heat sources – detection field geometry and distance (photometric
dis-tance law)
Figure
5
: Size, insulation and contrast of heat sources
Interference sources for motion detection
In addition to the mentioned effects, other objects within the detection area could also trigger
the motion detector, e.g.:
– Heat sources such as heating units, outlets from ventilation openings or air conditioners,
copiers, printers, coffee machines, etc. (Figure
6
)
– Draughty doorways
– Incandescent lamps when switching on or off
– Animals, e.g. stray cats
– Reflections on reflecting surfaces (Figure
3
)
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32597025 05.09.2018
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