PIR Motion Sensor HC-SR501
A passive infrared sensor that detects motion from warm bodies (humans, animals). Output goes HIGH when motion is detected.
Overview
A PIR (Passive Infrared) sensor detects changes in infrared radiation caused by warm objects moving across its field of view. It does not emit any signal -- it only listens. When motion is detected, the output pin goes HIGH (3.3V). The HC-SR501 module includes adjustable sensitivity and delay potentiometers.
Allow 30-60 seconds of warm-up time after powering on before readings stabilize.
Specifications
| Parameter | Value |
|---|---|
| Detection Range | 3 - 7 meters |
| Detection Angle | 120 degrees |
| Output Voltage | 3.3V HIGH |
Wiring Guide
| Sensor Pin | Arduino Pin |
|---|---|
| VCC | 5V |
| GND | GND |
| OUT | Any digital pin |
Adjust sensitivity and delay time using the two onboard potentiometers.
Usage in ArduinoStudio
Drag the IR Motion component onto the canvas, assign a digital pin, and use the motion detected event in your sequence. Pair with a relay to turn on lights automatically or with a buzzer for a simple alarm system.