Motion Sensor Light Switches

One type involves a separate unit for the motion detector and controller and a separate unit for the power supply and switch (relay) . This setup is the most current type of occupant sensor and is generally the least expensive. A more current innovation is called a wall box sensor and includes all the components housed in a single compact package. Wall box sensors are generally less noteworthy in terms of their detection capabilities than their older counterpart.

Another type of motion sensor uses infrared heat energy generated by a person. These passive devices do not emit any radiation and are strictly detection devices that are designed to be sensitive to any object that emits energy at a wavelength of approximately 10 microns, which is the maximum generated by a person. These devices are generally known as passive infrared sensors or PIR and are restricted by the fact that they are line-of-sight systems.
Motion Sensor Light Switches
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