The water level controller cum indicator is common nowadays. It is built using timer NE555, inverter buffer CMOS IC CD4049 and ULN2003.The [[wysiwyg_imageupload::]]components used here have low cost, are easy to build and install on the overhead tank so as to prevent wastage of water. This circuit of this project is simple, economical and versatile. It is used to switch on the motor pump when the level of water falls below the lowest level and turns off the motor when the tank is full. This project has a very simple circuit consisting of 3 probes which are used for automatic fill and cut of the water supply in tank. These are GROUND, HIGH and LOW. The GROUND probe is used for the reference. When the circuit is powered up for the first time the pump should be started automatically if the vessel is empty (or the level is below the required minimum level). As the HIGH level of the probe is reached, the pump must STOP. If the tank/container is already FULL then nothing should happen.
Water level controllers are quite common nowadays. This circuit is based on popularly used IC555 IC. Water level controller circuits have these advantages: Mostthe circuit only display the amount of water present in circuit, but this circuit will “on” and “off” the motor according to the level of water present in tank. It will not automatically stop the motor when tank is fill but it will “on” the motor when water in tank reaches below a specific point. It can be easily installed in over headed tanks because of less components used in circuits. It prevents the wastage of water due to over flow of tank. Can be operated with the help of 12V battery or adaptors (converts 230V AC to 12V DC) readily available in markets.