The PIR has two adjustment potentiometers on the back.
  1. The first adjusts the sensitivity of the sensor. You should start with a reading towards the "min" side, and adjust clockwise as necessary.
  2. The second adjusts the time the sensor stays "latched" or in the on state. When testing, leave this at the left which is a short time. Adjust clockwise for longer intervals.
Test the unit by making all the connections and the PIR is pointed away from movement or covered by a cardboard box. The green square should be displayed.
Move in front of the sensor and the red X should be displayed.
If the display does not change, check your wiring to the sensor and the potentiometers.

Once it is working, you can adjust the potentiometers to increase sensitivity and/or the delay used.

One programming note: the Arduino delay software routine cannot be used with the libraries as it adds a bit too much code. Try to adjust using the PIR potentiometers.


Mount the display box near the entrance to the room monitored. Mount the PIR sensor so it has a "field of view" of a wide area of the inside of the room. For a conference room, the table area would be best (do not aim above peoples heads).

Run power from an outlet to the display box. Ensure you have a 5 volt DC supply.
If you only want the display to show through the clear cover, you can make a mask from white paper. You can have the LED display show through the paper or cut out a square just for the display.

This guide was first published on Dec 18, 2013. It was last updated on Dec 18, 2013.

This page (Wrap-up ) was last updated on Dec 15, 2013.

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