Big Dome PIR Motion Detection Sensor Module HC-SR501

The HC-SR501 PIR (Passive Infrared) Motion Sensor is a low-cost and widely used module for detecting motion. It detects changes in infrared radiation, typically caused by moving objects like humans or animals.

Technical Specifications

• Power Supply: 5V to 12V DC
• Output Voltage: 3.3V logic signal (high when motion is detected)
• Detection Range: 3 to 7 meters (adjustable)
• Delay Time: 5 seconds to 5 minutes (adjustable)
• Trigger Modes: Single Trigger (default) and Repeat Trigger
• Lens Angle: About 120 degrees
  

Pinouts:

Connection with Arduino:

Module	Arduino UNO
VCC	5V
GND	GND
OUT	Pin 2

 

Sample code:

const int pirPin = 2;   // HC-SR501 output pin

 

void setup() {

  pinMode(pirPin, INPUT); // PIR sensor as input

  Serial.begin(9600); // Start serial communication

}

 

void loop() {

  int motionDetected = digitalRead(pirPin); // Read PIR output

 

  if (motionDetected == HIGH) {

    Serial.println("Motion Detected!");

  } else {

    Serial.println("No motion Detected!");

  }

  delay(100); // Small delay to reduce noise

}