WATER LEVEL CONTROLLER

This circuit can stop the working of water pump when the overhead tank is full. Relay connected to the circuit triggers and breaks the power to the water pump.

The circuit uses the CMOS IC CD 4001 to drive the relay. When the probe A connected to the  inputs of gate 1 of IC is floating, output of IC1 remains low and the transistor T1 remains non conducting. Water pump then gets power through the common and NC contacts of the relay. When the water level rises, probe A and B gets electrical continuity and the output of IC1 turns high and activates the relay. The breaks the power to the pump.

Note : When the probes are free, circuit becomes active. LED and relay turns on. When water makes contat with the probes, relay turns off.

Relay is not included in the kit.LED indication can be used to confirm the the On/Off action of  the relay.

Note

If component removal is required for re assembling, do not bend the excess leads of components before soldering. Cut the excess lead close to the PCB and apply some flux. Apply little solder at the contact point. Do not apply, excess solder or over heat the solder points. PCB tracks will detach. Clean the surface with kerosene, or PCB cleaning fluid to remove flux and dirt.