PIR Motion Sensor - sensoreact.com

Overview

PIR (Passive Infrared) motion sensor detects human motion through infrared radiation. Great for security systems and auto-lighting applications. The sensor detects changes in infrared energy emitted by warm bodies and triggers when motion is detected within its range. It's widely used in automatic lighting, security alarms, and home automation systems.

Technical Specifications

Operating Voltage: 4.5–12 V DC

Operating Current: < 50 µA

Detection Range: 3–7 m

Detection Angle: 110°

Output: Digital (HIGH / LOW)

Delay Time: 5 s – 300 s (adjustable)

Block Time: 2.5 s (default)

Operating Temperature: −15 °C to +70 °C

Key Features

Passive infrared detection technology
Wide detection angle (110 degrees)
Adjustable sensitivity and delay time
Low power consumption
Digital output signal
Easy integration with microcontrollers
Weatherproof versions available
No false triggers from pets (when properly adjusted)

Wiring Diagram

Basic Connection (Arduino Uno)

PIR Pin → Arduino Pin

VCC → 5V

GND → GND

OUT → Digital Pin 2

Note: Allow 1-2 minutes warm-up time after powering on for stable operation.

Common Applications

Security Systems

Intruder detection and perimeter monitoring

Automatic Lighting

Motion-activated lights for corridors and rooms

Home Automation

Smart home systems and occupancy detection

Energy Saving

Automatic appliance control based on presence

Quick Info

Difficulty: Beginner

Price Range: ₹100-250

Interface: Digital Output

Compatible Boards

Sample Code

#define PIR_PIN 2
#define LED_PIN 13

void setup() {
  Serial.begin(9600);
  pinMode(PIR_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
  
  Serial.println("PIR Motion Sensor Test");
  delay(2000); // Warm-up time
}

void loop() {
  int motionState = digitalRead(PIR_PIN);
  
  if (motionState == HIGH) {
    digitalWrite(LED_PIN, HIGH);
    Serial.println("Motion Detected!");
  } else {
    digitalWrite(LED_PIN, LOW);
    Serial.println("No Motion");
  }
  
  delay(500);
}