This post is dedicated to all those lazy fellas who don't want to make effort in closing the damn switch of Motor when the Tank has filled.
This is the circuit diagram of the Water-Tank Overflow Checker.
The circuit is simple; only assume that the Button Icon(fig) is the two wire open connection fixed inside the water tank at the desired level to check the overflow, and the DC motor is the water pump, which is connected to the default ON switch of the Relay.
WORKING:
As long as the tank is not completely filled, open connection of wires is not shorted by water, so it is like that the Button is not pressed, so Transistor Q1 will be in Cut-Off state, and Green LED will continue to glow and motor will keep pumping water. But as soon as the tank got filled the two wires will get shorted by water, so we can say that the Button is pressed, this will make the transistor Q1 ON and hence the relay toggles, cutting the power supply of the motor, which is indicated by the RED led.
Components Required:
- Two 1k & One 100 ohm Resistor
- One NPN transistor
- 6 volt. Relay
- 3 mm Red & Green LED
- 12 volt Rectifier Circuit( For DC circuit power supply)