Automatic room light controller without microcontroller

It is an easy guide with circuit diagram to make automatic home light with out micro controller or arduino

How it works

It works with PIR motion sensor.when leaving object moves in front of sensor then it’s out put pin become high.we are using a NPN transistor via 10K resistor to drive a relay. that means when sensor out put pin become high then relay turn on & also ac lamp turn on.

This PIR (Passive infrared sensor) can work up to 12 to 15 ft. you can control it’s sensitivity using potentiometer on it also you can control it’s timing delay & trigger sense using jumper & 2 potentiometer on it.

Parts List –

  1. HC-SR501 PIR Sensor
  2. 6 volt relay
  3. NPN transistor BC 548 B
  4. resistor 10K
  5. TP4056 Battery Charging Module Board
  6. Ac lamp holder ,wire , AC Plug
  7. Mobile charger for power supply
Circuit diagram of automatic room light

Video tutorial of this project


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