PIR Motion Sensor SR501 (Infrared Motion Detector)

👁️ PIR Motion Sensor – HC-SR501 (Infrared Motion Detector)

The HC-SR501 PIR Motion Sensor is a popular, low-cost infrared sensor used to detect human motion. It senses changes in infrared radiation, making it ideal for automatic lighting systems, security alarms, robotics, and home automation projects. The sensor includes adjustable sensitivity and delay time via onboard potentiometers.

⚙️ Technical Specifications

✅ Features

• 🔎 Detects motion from people, animals, or objects

• 🔧 Two adjustable knobs for delay and sensitivity

• 🔁 Can be set to trigger once or repeatedly while motion persists

• 🛠️ Easy to use with Arduino, Raspberry Pi, ESP32

• ⚡ Works with relays, buzzers, or smart lights

🛠️ Arduino Connection Guide

🧪 Arduino Example Code

int pirPin = 2;
int ledPin = 13;

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  if (digitalRead(pirPin) == HIGH) {
    digitalWrite(ledPin, HIGH);
    Serial.println("Motion detected!");
    delay(500);
  } else {
    digitalWrite(ledPin, LOW);
  }
}

🎥 YouTube Tutorial