Adjust depending on your application. The actual PIR Sensor i.e. The higher the potentiometer, the more sensitive the sensor will be. You can trace the pins by looking at the BISS001 datasheet and figuring out what pins they are - R10 connects to pin 3 and R9 connects to pin 7. the capacitors are a little tougher to determine, but you can 'reverse engineer' them from timing the sensor and solving! The actual sensor is inside a sealed metal can. The sensors sensitivity range between 6 to 7 meters (20 feet) and the detection angle is 110 degrees x 70 degrees. The sensitivity potentiometer can’t really be quantified, but it reacts intuitively. Each object with a temperature above absolute zero (-273.15° Celsius, -459.67° Fahrenheit, or 0 Kelvin) will radiate infrared, even us humans, and even though we mere humans cannot see this. In this example an LED will light up when movement is detected. Under normal condition where there is no movement in front of the sensor, both the slots in the Sensor detect same amount of infrared radiation. Connect GND with GND on Arduino. PIR sensor has three terminals - V cc, OUT and GND. The sensor in the PIR detects or “reads” infrared radiation “emitted” from objects all around us. Determining R10 and R9 isnt too tough. PIR Sensor Sensitivity Adjustment Variable Resistor: As it’s quite clear from its name sensitivity adjustment, this variable resistor is used to control the sensitivity of the PIR sensor. You can adjust the sensor sensitivity and delay time via two variable resistors located at the bottom of the sensor board. Detecting motion with the PIR motion sensor. For this example, you need the … The sensor in the figure above has two built-in potentiometers to adjust the delay time (the potentiometer at the left) and the sensitivity (the potentiometer at the right). The can basically protects the sensor from noise, temperature and humidity. Unfortunately this PIR sensor is mislabeled (it looks like they swapped R9 R17). There is a tiny window made of IR-transmissive material to allow the IR signals to reach the sensor. I have mine cranked to 11 ;-) the one which is covered with a lens, consists of two slots and both these slots are made up of IR Sensitive materials. Connect OUT to digital pin 2 on Arduino board. If not properly adjusted it can create a problem due to which you will always get a high signal. Connect the sensor as follows − Connect the +V cc to +5v on Arduino board.