Motion sensor light switch project using PIR motion sensor and relay module. We can use this motion sensed circuit as automatic night lamps, bedroom lights etc.Here we are not using any microcontroller or IC.

Motion sensor light

When any one enters the room the motion sensor senses the motion, the motion sensor turn on its output automatically and turn on the light.

If the person leaves the room the pir motion sensor will turn of its output and thus turn off the light.

We can control the on time and off time interval of motion sensor by adjusting the potentiometer.

How motion sensor light bulb circuit works

1. PIR motion sensor is a motion detection module which works in 3.3 volt DC.

2. The regulator is known as LDO( Low drop output) which is very effecient in regulating voltage. Normally motion sensor module is powered from 3.3 VDC to 12 VDC.

3. The sensor can detect microwave radiation in the form of heat variation happening in a room.

Human beings emits small amount of radiation to the outside world.circuityep. com.This energy is detected by fresenl lens on PIR motion sensor and given to the comparator ic of sensor. The sensor compares the analog value and a proportional digital value is created at the output.

Components Required

1. PIR Motion Sensor Module

2. Relay ( 6 Volts DC - 230 V AC )

3. Resistor - 1 kiloohms

Motion sensor light switch