Ultrasonic motion detector

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The ultrasonic motion detector is an existing from an ultrasound transmitter and receiver motion detector responsive to a change (set-actual comparison) of the emitted by the detector and received as a reflection ultrasonic waves ( ultrasound ) is responsive in the monitoring area ( Doppler effect ) , e.g. B. on a person (or animal) located in this area, and indicates this by interrupting the reporting line (active detector).

The monitored volume has an "egg-shaped" shape. The carrier medium for the sound waves is air. For this reason, ultrasonic motion detectors must not be installed behind curtains, above radiators, in the area of ​​ventilation inlets or outlets, in the vicinity of strong sound sources or in the area of ​​loosely suspended objects (e.g. lamps).