Arduino Human Infrared Sensor I started out again with Arduino (beginner), but I wanted to know if I could connect another human infrared sensor like this to the Arduino Uno. I know how to connect a simple pir like this one, but I dont know for sure how to connect the 12V one (if its possible). Guess the red wire goes to a seperate 12V power supply, brown goes to ground and blue then goes to a digital pin on the arduino arduino? I didnt really understand the description that was available for the 12V sensor, so thats why I am asking (I want to be entirely sure before buying).

Thanks
Blue - Ground, connect to Arduino GND
Brown - Power, connect to external 12V source.
Red - 12 V output. Connect via a diode to arduino input pin. Enable pullup on arduino pin.

This way when the sensor output is low it will pull the arduino pin low. When the output is high the diode blocks the 12V from frying the arduino while the internal pullup ensures the input pin goes to a safe voltage for a high pin.

Don't put the diode the wrong way around or things will go bang.







simulate this circuit &ndash; Schematic created using CircuitLab