Hello,and welcome back to Enghme.Water Level Indicator Circuit Using Transistor is one of the easiest and popular projects in electronics projects.
We usually worry about wasting water when we turn on the motor and forget to turn it off. The water level indicator uses a simple mechanism to detect and indicate the water level in an elevated water tank or any other water container. We have released the water level indicator and controller using IC ULN2003. In this article, we have shown a very useful, cheap and simple water level indicator circuit using transistors (bc547) for beginners. This circuit uses LEDs with transistors to indicate the water level in the tank. You can use this project as a university project.
Circuit components:
# 4 – BC547 transistor
# 3-220 ohm resistor
# 3 – LED
# 1-Buzzer
# 5 – 9v battery + battery clip/power supply
Circuit Diagram
The circuit diagram above shows the connection arrangement. Use +9V power supply or battery. In this circuit, we used all transistors as switches. Water touches the contact between the wire and the base of each transistor. A small current flows through the base and turns on the transistor when the transistor is turned on. The LED connected to it emits light. The LED will turn on according to the water level. We used a buzzer on the last transistor because the water touches the base of the collector of the last transistor, and the collector and emitter are connected, and the buzzer sounds. You can connect a relay instead of a buzzer to automatically control the water level in the water tank.