FLOAT SWITCH or FLOAT SENSOR WITH ARDUINO

A float sensor or float switch is used to detect the level of liquid within a tank. It is also called as magnetic float sensor or float switch as its working is same as of switch. Magnetic float sensor is an electromagnetic ON/OFF switch. It senses the level of water present in the tank by making switching connection.

WORKING OF FLOAT SWITCH

To make a circuit closed/complete circuit float sensor use magnetic reed switch. Then what is reed switch?

Reed switch

It is an electrical switch which can operate/work by applying magnetic field. It consists of ferromagnetic flexible metal reeds contact isolated in hermetically sealed glass envelop.

The metal contact is normally open. But as we applied magnetic field or place a magnet near one metal end of the switch it attracts the other end of metal, which makes path for current to pass through. When the magnet moves far away the switch, the contacts demagnetize and will separate (breaking the circuit).

Float sensor is working on the same concept as reed switch, but one more question might be arising. In reed switch we are using magnet but how can we get magnet in water tank? Right! We don’t need to worry about it because float sensor is being designed in that manner magnet is already presents there.

When we outfit sensor in an empty tank the switch position is at bottom but as water starts filling up switch position rises up which generates magnetic field for the reed switch. So simply, when water level goes down sensor break the circuit and series led connected will turned off, while when level goes up sensor make the circuit and series led connected will turned on.

REQUIRED HARDWARE

CIRCUIT DIAGRAM – INTERFACING OF FLOAT SWITCH WITH ARDUINO

Make the following connections with Arduino

FLOAT SENSOR ARDUINO CODE

int FloatSensor = 2;
int led = 13;
int buttonState = 1; //reads pushbutton status

void setup() {
  Serial.begin(9600);
  pinMode(FloatSensor, INPUT_PULLUP);
  pinMode (led, OUTPUT);
}

void loop() {
  buttonState = digitalRead(FloatSensor);

  if (buttonState == HIGH) {
    digitalWrite(led, LOW);
    Serial.println("WATER LEVEL - LOW");
  }
  else {
    digitalWrite(led, HIGH);
    Serial.println("WATER LEVEL - HIGH");
  }
  delay(1000);
}

OUTPUT

After uploading the code successfully, you can see when water level goes up led attached will get turn on and when water level goes down led will get turn off.