How to Use IR Beam Break Sensor: Examples, Pinouts, and Specs

An IR (Infrared) beam break sensor is an electronic device that detects the presence or absence of an object based on the interruption of an infrared light beam. The sensor consists of an infrared emitter and a receiver. When an object passes between the emitter and receiver, the beam is broken, and the sensor outputs a signal indicating the event. This type of sensor is commonly used in applications such as security systems, manufacturing line item counting, and user input for electronics.

• Intruder detection in security systems
• Item counting on conveyor belts
• Elevator door safety systems
• User input for interactive installations

• Operating Voltage: 3.3V to 5V
• Current Consumption: 10mA (typical)
• Output Type: Digital signal (High when beam is unbroken, Low when beam is broken)
• Wavelength: 940nm (infrared)
• Sensor Range: Up to 30cm (with proper alignment)
• Response Time: <2ms

1. Connect the VCC pin to a 3.3V or 5V power supply.
2. Connect the GND pin to the ground of the power supply.
3. Connect the OUT pin to a digital input pin on a microcontroller, such as an Arduino UNO.

• Ensure that the emitter and receiver are properly aligned for the sensor to function correctly.
• Avoid exposing the sensor to direct sunlight or strong artificial light sources that may interfere with the infrared signal.
• Use a pull-up resistor if the microcontroller input pin does not have an internal pull-up feature.

// Define the pin connected to the IR beam break sensor
const int beamBreakPin = 2;

void setup() {
  // Initialize the beamBreakPin as an input
  pinMode(beamBreakPin, INPUT);
  // Begin serial communication at a baud rate of 9600
  Serial.begin(9600);
}

void loop() {
  // Read the state of the beam break sensor
  int beamState = digitalRead(beamBreakPin);
  
  // Check if the beam is broken
  if (beamState == LOW) {
    // Beam is broken
    Serial.println("Beam broken!");
  } else {
    // Beam is unbroken
    Serial.println("Beam intact.");
  }
  
  // Small delay to avoid overwhelming the serial output
  delay(100);
}

• Sensor not responding: Ensure that the sensor is properly powered and that the pins are correctly connected.
• False triggering: Check for any sources of infrared light interference and ensure that the sensor is not exposed to direct sunlight.
• Inconsistent detection: Verify that the emitter and receiver are correctly aligned and that there are no obstructions in the beam path.

• If the sensor output is erratic, consider adding a debounce circuit or software debouncing to the input reading.
• For issues with detection range, adjust the distance between the emitter and receiver for optimal performance.
• Ensure that the sensor is mounted securely to prevent misalignment due to vibrations or accidental movement.

• Q: Can the sensor be used outdoors?

  • A: The sensor can be used outdoors but should be shielded from direct sunlight and harsh weather conditions.

• Q: What is the maximum range of the sensor?

  • A: The maximum range is approximately 30cm, but this can vary based on environmental conditions and alignment.

• Q: How can I extend the range of the sensor?

  • A: Extending the range beyond the manufacturer's specifications is not recommended as it may lead to unreliable performance.