Active Infrared Beams Detectors (IR Beams) adopt the invisiable infrared detection technology. It consists of receiver and transmitter, transmitter emit the (2-4 beams) infrared beam, and the receiver will receive the beam.

VSH is a Quadruple Synchronized Beams sensor (four beams). The Four Beam
ensures minimum false alarm possibility against falling leaves, birds, small
animals etc. This beam sensor comes with laser beam alignment function which reduces the installation time and along with that increases the workability of the device. The Beam sensor comes with built-in Optical Viewfinder for easy and quick alignment. One more
notable feature of this beam is Automatic Gain Control (AGC) Circuit for precision. Other features include Weather proof Anti-rain, snow, dew, mist, frost
design mounting brackets, Pole Clips etc. The protection distance (between Transmitter / Receiver) should be placed in the rated range.

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