user15984: I recently bought an HC-SR505 Mini PIR sensor. I connected its positive to my Arduino UNO's 5v, output to digital pin 2, and ground to ground. I used Adafruit's code to test it, but all the serial monitor displayed was "Motion detected", which meant the PIR was always on a HIGH state. I then also tried powering it using 3V3 but the PIR kept on cycling on a HIGH and LOW state. Any help on getting my sensor to actually work would be greatly appreciated.

user28085: The PIR sensor has delay of 8 seconds. So when you turn on arduino, take care that no movement is on the PIR, and then after 8 seconds it should detect no movement. And it has always this delay,every time when detects movement. 

15984: <p>I recently bought an HC-SR505 Mini PIR sensor. I connected its positive to my Arduino UNO's 5v, output to digital pin 2, and ground to ground. I used Adafruit's <a href="https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor/using-a-pir" rel="nofollow">code</a> to test it, but all the serial monitor displayed was "Motion detected", which meant the PIR was always on a HIGH state. I then also tried powering it using 3V3 but the PIR kept on cycling on a HIGH and LOW state. Any help on getting my sensor to actually work would be greatly appreciated.</p>
 28085: <p>The PIR sensor has delay of 8 seconds. So when you turn on arduino, take care that no movement is on the PIR, and then after 8 seconds it should detect no movement. And it has always this delay,every time when detects movement. </p>
