PIR Infrared Motion Sensor (HC-SR501)

PIR sensors, often referred to as, "Passive Infrared" or "IR motion" sensors, enable you to sense motion. Everything emits a small amount of infrared radiation (IR), and the hotter something is, the more radiation it emits. PIR sensors are able to detect a change in average IR levels of their detection zone (e.g. when a human enters a room, that room will increase in temperature slightly) and hence sense motion.

This one's great, as it can be powered via the Raspberry Pi's 5V output, and be read directly from the Raspberry Pi's GPIO input (as the sensor has a digital 3.3V output!)

• Input Voltage: 4.5V - 20V
• Current Draw: <50µA
• Digital Output: 3.3V (High)
• Digital Output: 0V (Low)
• Working Temperature: -15°C to 70°C
• Delay Time: 0.5 - 200 Seconds
• Sensing Angle: 100° Cone
• Range 5m - 7m
• Dimensions
  • Sensor Lens Diameter: 23mm
  • Length: 24.03mm
  • Width: 32.34mm
  • Height (with lens): 24.66mm
  • Centre screw hole distance: 28mm
  • Screw hole diameter: 2mm (M2)