1.When the module detects the obstacle signal in front of it, the green indicator light on the circuit board will light up the level and the OUT port will continue to output the low leval signal.The detection distance of the module is 2~30cm and the detection Angle is 35°. The detection distance can be adjusted by the potentiometer,and the potentiometer is adjusted clockwise to increase the detection distance. Counter clockwise potentiometer, reduced detection distance. 2. the sensor active infrared reflection detection,so the rerlectivity and shape of the target is the key to the detection distance. Among them, the detection distance of black is the smallest, and the detection distance of white is the largest: the distance of small area objects is large. 3. the sensor module output port OUT can be directly connected with the MCU 10 port, can also directly drive a 5V relay; Connection mode:VCC-VCC;GND-GND; 0UT-10 4. comparator using LM393,stable work;5.3-5V DC power supply can be used to supply power to the module. When the power supply is connected, the red power indicator light is lit 6.with 3mm screw hole, easy to fix and install 7.circuit board size :31mmx15mm 8.Each module has adjusted the smell value comparison voltage through the potentiometer before delivery. Unless special circumstances, do not adjust the potentiometer at will