PIR Circuits, Utility GadgetsHow to fix PIR sensor Alarm PIR sensor is the ideal device to use as Surveillance systems that operates by sensing human body heat. It triggers the alarm from a distance of 10 meters when a human passes. It operates both day and night. Let us see how to fix it on the wall Share this:PrintFacebookTwitterLinkedInEmailRedditTumblrLike this:Like Loading... Related