This project automatically turns on a light when someone enters a room or passes by. It uses a PIR (Passive Infrared) sensor to detect motion and then switches on a bulb or LED.
Key Components Required
- Arduino UNO board ►https://amzn.to/3opv2lP
- 10KΩ resistor ►https://amzn.to/3fqfeLl
- 16MHz oscillator ►https://amzn.to/33PvYGG
- 22pf Capacitors-(2) ►https://amzn.to/3bA7N3n
- PIR sensor ►https://amzn.to/33T10gJ
- 5v DC supply/battery
- 5v relay ►https://amzn.to/3fp8uxv
- BC547 transistor ►https://amzn.to/3bzNItW
- AC Plug & Bulb holder ►https://amzn.to/2T0bhWn
- Led Light ►https://amzn.to/3tW2hyh
- IN4007 diode ►https://amzn.to/33T2MOV

PIR Sensor Connections
| PIR Sensor Pin | ATmega328P Pin |
| Out (Signal) | Pin 4 (Digital Pin D2) |
| VCC (Power) | Pin 7 (VCC / +5V) |
| Ground | Pin 22 (GND) |
Working
- The PIR sensor detects heat from a moving person.
- This signal goes to the Arduino, which processes the motion detection.
- When motion is detected, the Arduino activates the transistor.
- The transistor switches on the relay, which then turns on the bulb or LED.
- When no motion is detected anymore, the relay turns off, and the light goes out.
Watch the full video tutorial here: How to make a Motion Sensor Light at Home | PIR sensor | Arduino | Using Arduino chip on Zero PCB

