It is a simple automatic water pump controller by just using NOR gates of 4001 NOR IC. The IC will trigger the transistor to activate the relay and switches on automatically the water pump motor to fill the tank . The logic 1 means the low sensor and high sensor will be reached by water level inside the tank. The logic 0 means that the water level falls below the high sensor . here, the high sensor and low sensor are represented by steel rod in the actual circuit . when the logic 1 has achieved, it means that the sensor has been touched the water level and the 12 volts supply has passed through the water which has a resistance that DC current can flow.
