Robot Water Tank Overflow Alarm with 4 Level Indicator

Worried about wasting water due to tanks overflowing? Now with this simple alarm you can always know when the tank is about to overflow and you can save water and do you part of good to mother nature. This circuit not only indicates the amount of water present in the overhead tank but also gives an alarm when the tank is full. The circuit uses the widely available CD4066, bilateral switch CMOS IC to indicate the water level through LEDs. When the water is empty the wires in the tank are open circuited and the 180K resistors pulls the switch low hence opening the switch and LEDs are OFF. As the water starts filling up, first the wire in the tank connected to S1 and the + supply are shorted by water. This closes the switch S1 and turns the LED1 ON. As the water continues to fill the tank, the LEDs2 , 3 and 4 light up gradually. The system provides visual water level indication with audio alarms at desired levels. * Now no need to go on the roof to look the water level. * It shows the water level in your room like 1/4 tank, 1/2 tank, 3/4 tank and full tank. * Alarm starts ringing as soon as tank becomes full. * Suitable for every tank.