Introduction: Automatic Water Tap Using 555 Timer

This project is sensor based automatic water tap. The tap starts whenever anyone put his/her hand in front of sensor which is below the water tap.

The Ir sensor is made using 555 timer, used as astable multivibrator, vibrating at around 38 KHz. and another 555 timer ic is used as monostable multivibrator for tap circuit.

Step 1: Parts Needed

For Sensor Circuit
  • lm555 timer ic
  • 103pf ceramic capacitor
  • 18k resistor
  • 1k resistor
  • 22R resistor
  • 102pf ceramic capacitor
  • IR led
  • 4.7uf electrolytic capacitor
  • 10k resistor
  • 100R resistor
  • TSOP1738 IR receiver
  • red leds

For Main Circuit

  • 12-0-12 step down transfarmer
  • 1N4007 diode
  • LM7805
  • 1000uf electrolytic capacitor
  • BT136 triac
  • LM555 time ic
  • red leds
  • 1k resistor
  • 10k resistor
  • 103pf ceramic capacitor
  • 100k resistor
  • 100R resistor
  • BC547 transistor
  • Solenoid Valve (you can get one from old automatic washing machine)
  • Dotted PCB

Optional Parts

  • Wash Basin
  • wash basin stand
  • plyboard
  • Colors

Step 2: Circuit Diagrams

Here are both of the circuit diagrams for IR sensor and master circuit. I have also included eagle schematic files.Make both the circuits on different PCBs.

The Sensor Circuit

The sensor circuit is based on the 555 timer ic in astable mode. 555 timer ic vibrates at 38KHz and that waves are transmitted using IR led and if any obstacle is in front of IR led the rays reflects and the TSOP1738 IR receiver modules recieves and sends signal.

The Main Circuit

In main circuit 555 timer ic is used in monostable mode hence when it receives any signal from IR sensor then automatically enables the solenoid valve for some time and then automatically turn off the output current in BT136 Triac.

Step 3: Assembling

You may assemble the things like as shown in images or use your own way.

Step 4: Final Touch

I have Used Colors and some lightening connections to make it more attractive.