Water level controller circuit using transistors and NE555 timer IC

A simple water level controller circuit utilizing a 555 integrated circuit (IC) and six transistors. A relay is employed for controlling the pump motor.

This water level controller circuit is designed to monitor and manage the water level in a tank or reservoir using a 555 timer IC, which serves as the central control unit. The circuit operates based on the principles of detecting water levels through conductive probes or float switches, which trigger the operation of a relay to control a pump motor.

The 555 timer can be configured in astable or monostable mode, but for this application, it is typically set up in monostable mode to provide a pulse when the water level drops below a certain threshold. The six transistors in the circuit are used to amplify the control signals and drive the relay, allowing for the switching of higher currents needed for the pump motor.

When the water level falls below the designated point, the probes detect this condition, and the 555 timer outputs a signal. This signal is fed to the first transistor, which acts as a switch to turn on the subsequent transistors in the circuit. Each transistor amplifies the current until the final transistor activates the relay. The relay, in turn, energizes the pump motor, which begins to fill the tank with water.

Conversely, when the water level rises to the set point, the probes again detect this condition, causing the 555 timer to cease its output signal. This action turns off the transistors sequentially, deactivating the relay and stopping the pump motor from operating, thus preventing overflow.

The circuit design may include additional features such as LED indicators to show the operational status of the pump, as well as protection diodes to prevent back EMF from damaging the transistors when the relay coil is de-energized. Overall, this water level controller circuit is a practical and efficient solution for automating water management in various applications.A very simple water level controller circuit based on 555 IC and 6 transistors. A relay is used for switching the pump motor.. 🔗 External reference