21 Mar 2012

DIY Water Level Controller

This is a project I had to complete within four days in school. It is an extremely reliable water level controller which can serve you for years without giving any problem. Unlike some automatic water level controllers, this system will not damage your pump as it will switch it on only if the underground tank is full. So build this circuit, save water and have fun!

Materials Required
  • 12A Relay
  • 12V 1A Transformer
  • PCB
  • Blue LED, 1 Red LED, 1 Green LED
  • Diodes
  • 1k Resistors
  • 10k Resistor
  • 2200 microfarad Capacitor
  • Toggle switch
Tools Required
  • Soldering Iron
  • Hand Drill
  • Screw Driver
  • Wire Stripper

Water Level Controller Circuit Diagram
Step by Step Guide:
  • Follow the circuit diagram and solder the components accordingly
  • Solder the wires going to the underground tank to the place marked 'UG' in the diagram
  • Solder the wires going the the overhead tank to the place marked 'OH'
  • Solder the relay's coil pins to the place marked 'Relay'
  • Solder the transformer's secondary wires to the place marked 'AC voltage source
  • Drill holes in the box for the power cables to come in and for the 'OH' and 'UG' wires to go out
  • Solder the transformer's primary wires to the live and neutral wires  through the toggle switch
Automatic Water Level Controller circuit


This completes the core circuit of the Water Level Controller. To test your circuit, short the 'UG' wires together and short the 'OH' wires. This should light up the three LEDs. The 'Power' LED indicates power coming to the circuit board, the 'UG' LED lights up if the underground tank is filled and the 'OH' LED lights up indicating that he pump is running. Connect an incandescent bulb ( or any other) and a power source instead of the pump. If everything goes well, the bulb should light up representing the running state of the pump. Next:
  • Lay the 'OH' wires till the overhead tank and the 'UG' wires to the underground tank and connect them to the float switches
  • Solder the live wire and the wire going to the pump to the relay pins
Now, let us go through the entire process... Water is almost finishing in your house. The 'OH' float switch turns on. When the underground tank gets filled, the 'UG' LED lights up, the 'OH' LED lights up, the relay coil gets powered and the pump is turned on. Once the overhead tank gets filled, the float switch in there turns over and the 'OH' LED goes off and the pump is immediately turned off.

So henceforth, you don't have to worry whether you are going to get water in the shower when you go for a bath and you will be also saving precious water without any efforts! 

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