Hall Effect Sensor With Arduino | Hall effect sensor | Ardui

Hall Effect Sensor With Arduino | Hall effect sensor | Arduino Tutorial

A Hall effect sensor is a device used to detect magnetic fields. When a magnet comes close to the sensor, it changes its output signal. These sensors are widely used in contactless detection systems, such as proximity sensors, speed detection, and current sensing. With Arduino, you can use Hall sensors to create interactive and automated electronics projects.

There are two main types of Hall effect sensors:

Digital Hall sensors (e.g., A3144, SS41) – act like switches. They output LOW when a magnetic field is detected and HIGH otherwise.

Analog Hall sensors (e.g., 49E, SS495A) – provide a variable voltage output depending on the strength and polarity of the magnetic field.

In the tutorial, a digital Hall sensor is used. The sensor has three pins: VCC, GND, and OUT. The wiring is straightforward:

Connect VCC to the Arduino’s 5V pin.

Connect GND to Arduino’s GND.

Connect OUT to a digital input pin (like D2)

The sensor detects when a magnet is nearby by pulling the OUT pin LOW. This signal can be used to trigger an LED, buzzer, or display a message on an LCD or Serial Monitor.

A sample Arduino code is provided to read the digital signal from the sensor. When the magnet is detected (OUT pin is LOW), an LED turns on, a buzzer sounds, and a message is printed. Here's a basic version of the code:

Components Required

Arduino UNO

16×2 LCD

Hall effect sensor

Buzzer

LED

I2C module

Jumper wires

breadboard

10K potentiometer

220-ohm resistor

USB cable for uploading the code

cpp

CopyEdit

const int sensorPin = 2;
const int ledPin = 13;

void setup() {
pinMode(sensorPin, INPUT);
pinMode(ledPin, OUTPUT);
Serial.begin(9600);
}

void loop() {
int state = digitalRead(sensorPin);
if (state == LOW) {
digitalWrite(ledPin, HIGH);
Serial.println("Magnet Detected");
} else {
digitalWrite(ledPin, LOW);
}
delay(100);
}

cpp

CopyEdit
const int sensorPin = 2;
const int ledPin = 13;

void setup() {
  pinMode(sensorPin, INPUT);
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int state = digitalRead(sensorPin);
  if (state == LOW) {
    digitalWrite(ledPin, HIGH);
    Serial.println("Magnet Detected");
  } else {
    digitalWrite(ledPin, LOW);
  }
  delay(100);
}

The Techatronic tutorial also shows how to connect an LCD to display the detection status. You can integrate a 16x2 LCD using the LiquidCrystal library to show real-time updates when a magnet is brought near the sensor.

This setup is ideal for projects like door sensors, RPM counters, or contactless switches. By placing a magnet on a rotating object or near a moving part, the Arduino can detect each pass and trigger actions accordingly.

If you're using an analog Hall sensor, the output is connected to an analog pin (e.g., A0), and the voltage is read using analogRead(). This allows you to measure the strength and direction of the magnetic field, which is useful for more advanced applications.

Troubleshooting tips include ensuring proper wiring, checking if the sensor has a built-in pull-up resistor, and verifying the magnet's strength and position. Some sensors may require a small delay to stabilize the output.

In summary, Hall effect sensors are easy to use with Arduino and offer powerful functionality for detecting magnets and motion. With just a few components and simple code, you can build responsive, magnetic-based systems for a variety of applications.