If the sensor is not behaving as expected, use the following troubleshooting steps:
Place an object at your desired maximum detection distance in front of the sensor. If the Obstacle LED does not turn on, rotate the potentiometer clockwise until the LED just lights up. Remove the object to ensure the LED turns off. Repeat and fine-tune as necessary. Hardware Interfacing
void loop() isObstacle = digitalRead(isObstaclePin); if (isObstacle == LOW) Serial.println("OBSTACLE!!, OBSTACLE!!"); digitalWrite(LED, HIGH); else Serial.println("clear"); digitalWrite(LED, LOW);
⚠️ : Typically, rotating the potentiometer clockwise (CW) increases the detection distance, and counter-clockwise (CCW) decreases it. Fc 51 Ir Sensor Datasheet
The electrical and mechanical parameters of the FC-51 module include: Value / Range 3.3V to 5.0V DC Operating Current ≥is greater than or equal to Detection Distance 2cm to 30cm (Adjustable via potentiometer) Detection Angle Output Type
Power LED (Red) and Obstacle Detection LED (Green/Red depending on the manufacturer) Working Principle The FC-51 operates on the principle of infrared reflection.
2cm to 30cm (Adjustable via onboard potentiometer) Detection Angle: 35 degrees If the sensor is not behaving as expected,
Placed along conveyor belts to count passing items in manufacturing setups.
By following this guide, you'll be well-equipped to work with the FC-51 IR sensor and explore its many applications.
If the reflected signal is strong enough (meaning an object is close), the LM393 pulls the OUT pin LOW and turns on the obstacle LED. The Impact of Surface Properties Repeat and fine-tune as necessary
Illuminates when an obstacle is detected within the set threshold.
The IR photodiode detects the reflected light. The intensity of the received light changes the resistance of the photodiode.
The FC-51 operates on the principle of infrared light reflection and comparative voltage thresholds.
Used in automatic hand sanitizers or touchless paper towel dispensers.
The changing voltage from the photodiode is sent to the LM393 voltage comparator IC. The LM393 compares this signal against a reference voltage set by the user via the onboard potentiometer.