Water-level indicator uses a 7-segment display, instead of LEDs, to indicate the water level (low, half and full) in the tank. Moreover, a buzzer is used to alert you of water overflowing from the tank. The circuit shows the water level by displaying L, H and F for low, half and full, respectively. The circuit uses five sensors to sense the different water levels in the tank. When water starts overflowing the tank, the buzzer blows. The buzzer sounds to indicate that water is overflowing the tank and you need to switch off the motor pump. In Water Level Indicator Using 7- Segment Display circuit uses five sensors to sense the different water levels in the tank. Sensor A is connected to the negative terminal (GND) of the power supply.