PIR Motion Detector Module

Description

Every human or animal body has a temperature. This temperature is continuously emitted from the body in the form of infrared waves. The PIR sensor detects these waves.
The PIR sensor consists of two sensors inside to detect IR waves. When any human or animal enters or moves in its field, then both the sensors inside experience a difference in the infrared waves and the sensor signals the presence of someone. When a human or animal is standing stationary in front of it, both the sensors get the same IR waves and the sensor does not give any signal. Therefore, this sensor is used to detect the movement of a human or animal. Hence it is also called Motion Sensor.