Header banner
Revain logoHome Page
Keith Harris photo
1 Level
1324 Review
44 Karma

Review on Stemedu Pack of 5 HC-SR501 PIR Sensor Infrared IR Body Motion Modules for Arduino Raspberry Pi by Keith Harris

Revainrating 5 out of 5

The output voltage was less than 3.3V

Motion detector works quite well. I tried using this to activate a 3V relay directly and had trouble activating the relay. Using a multimeter, I was able to find out that the output from these motion sensors is only 2.8 volts, which is just below the voltage threshold for the relay. Fortunately, the project also includes a Raspberry Pi, and 2.8 volts is enough to register as a high contribution to the Pi. So now I use the sensor as an input to the Pi and the Pi controls the relay. This part is good for motion detection. Note, however, that you may have trouble detecting it on some devices.

Pros
  • 🚩 Application: HC-SR501 can be used as a high-tech product. Suitable for companies, hotels, shopping malls, warehouses and family aisles, corridors. Or use automatic light, lighting and alarm systems for security area
Cons
  • Power socket required