Wednesday, November 11, 2015

110/220v Aoutomatic light switch (Photocell)

This is an automatic light switch circuit (Photocell), can run 220v lamps in night automatically up to 10A.
Advantages of this circuit:

1-have 5 seconds delay time
2-can run up to 10A load
3-can use for any lamp types such as LED, CFL, low pressure sodium, high pressure sodium, ...etc.
4-adjustable light sensitivity by potentiometer

Parts list:
Transistor 2N5551(2pcs)
Relay 12v
Potentiometer 25k
Bridge diode 1A
Zener diode 12v 1W
Diode 1N4007
Capacitor 330-820uF 400v
Capacitor 100uF 25v(2pcs)
Resistor 270 ohm 2W
Resistor 10k
Resistor 2.2k
Resistor 33 ohm
you must put it in a small transparent plastic box for electric and moisture insulation.
1-Don't touch the circuit when it connected to electric line.
2-Put it away from lamps light (above the lamp) 

As you see in this pic. i used 3A relay rather than 10A to make the circuit small as possible since my loads consume very low current

110/220v Aoutomatic light switch (Photocell)

110/220v Aoutomatic light switch

In following video you can see step by step making this Photocell: