Introduction

The E18-D80NK is an adjustable infrared proximity sensor with reliable detection range from 3cm to 80cm. This photoelectric switch features a potentiometer for sensitivity adjustment and provides both analog and digital output signals.

Key Features

Technical Specifications

Pin Configuration

Wiring with Arduino

// Basic Digital Connection:
// Brown → 5V
// Blue  → GND
// Black → D2 (or any digital pin)

// Optional Analog Connection:
// White → A0 (for distance estimation)

Adjusting Detection Range

1. Locate the blue potentiometer on the sensor body
2. Place an object at your desired detection distance
3. Slowly rotate the potentiometer clockwise to increase sensitivity (longer range)
4. Rotate counter-clockwise to decrease sensitivity (shorter range)
5. The onboard LED will turn off when an object is detected
   

   

Basic Digital Detection

const int sensorPin = 2; // Digital input pin

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

void loop() {
  int detection = digitalRead(sensorPin);
  
  if (detection == LOW) {
    Serial.println("Object detected!");
  } else {
    Serial.println("No object detected");
  }
  delay(100);
}

Analog Distance Estimation

const int analogPin = A0; // Only if white wire present

void setup() {
  Serial.begin(9600);
}

void loop() {
  int sensorValue = analogRead(analogPin);
  float voltage = sensorValue * (5.0 / 1023.0);
  
  // Approximate distance calculation (requires calibration)
  float distance = 80.0 * (1.0 - (voltage / 5.0));
  
  Serial.print("Analog Value: ");
  Serial.print(sensorValue);
  Serial.print("\tEstimated Distance: ");
  Serial.print(distance);
  Serial.println("cm");
  
  delay(200);
}

Advanced Applications

int objectCount = 0;
bool lastState = HIGH;

void loop() {
  bool currentState = digitalRead(sensorPin);
  
  if (lastState == HIGH && currentState == LOW) {
    objectCount++;
    Serial.print("Objects passed: ");
    Serial.println(objectCount);
  }
  
  lastState = currentState;
}

long lastDetection = 0;
float objectSpeed = 0;

void loop() {
  if (digitalRead(sensorPin) == LOW) {
    long now = millis();
    if (lastDetection > 0) {
      objectSpeed = 1000.0 / (now - lastDetection); // Hz
      Serial.print("Frequency: ");
      Serial.print(objectSpeed);
      Serial.println("Hz");
    }
    lastDetection = now;
  }
}

const int sensorPins[] = {2, 3, 4};
const int numSensors = 3;

void checkSensors() {
  for (int i=0; i<numSensors; i++) {
    if (digitalRead(sensorPins[i]) == LOW) {
      Serial.print("Sensor ");
      Serial.print(i);
      Serial.println(" triggered");
    }
  }
}

Troubleshooting