Me PIR sensors are used to detect motion from animals/ humans from about 6m away. If anyone moved in that range, the sensor outputs HIGH on its SIG pin. With a potentiometersoldered on its circuit board, you can adjust its detecting range according to your need. Here are some ideas for application: motion detecting, thief-guarding system, automation switch.
Note: when you give it power supply??you may need to wait 10 seconds until the sensor Initialize.
 
Features:
 Adjustable detecting range and high sensity
 A power indicator LED(Red) and a state indicator(Blue)
 16mm interval M4 mounting holes, compatible with Makeblock beams
 2.54mmbreakout pins for connecting with jumper wires
 Easy wiring with 6 Pin RJ11 interface
 Arduino library for easy programming
 
Specification
 Rated Voltage: 5V
 working temperture:-20?????70??
 Level output voltage: 5V/high, 0V/low
 Trigger signal: 5V/high
 Holding time: 2s
 Detecting angle: 120 degree
 Detecting distance: max 6m
 Size:24x48x 32mm(Length x Width x Height)