Simple Chopper Mechanism for PIR Sensors

A PIR cannot sense a motionless or a still human presence and will tend to switch OFF its output. However the PIR can be fooled by placing a chopper in front so that it alternately cuts the IR radiation from the motionless human. A PIR chopper is a system in which an oscillating object is placed in front of a PIR sensor so that the IR radiation from a human is "chopped" in an alternate manner before reaching the PIR sensor. This imitates a moving human for the PIR and forces it to remain ON as long as the human is present, even in a stationery condition.

Видео Simple Chopper Mechanism for PIR Sensors канала Swagatam