Automatic Night Lamp Circuit Diagram Using Ldr And Triac. In this project we are going to make an automatic night lamp with triac. The lamp used in this project is porch light which would turn on automatically in dark night time and turn off in light day time.
The circuit is divided in two parts first is a capacitor power supply and second part is an automatic night lamp circuit. The working of this night light circuit very simple. An ldr is used as the sensor here.
It is a high speed solid state device that is able to switch and control ac power in both directions of a sinusoidal waveform.
Automatic light operated switch circuit using ldr triac optocoupler without relay. An ldr is connected in the circuit detects the darkness nearby. The main part of this circuit is the light dependent resistor ldr. In the case when the room is dark the ldr inputs signal to the transistor 2n3904.
