This cheap, small, 3d-printable, battery powered node allows you to check if your windows or doors are open or close!

This useful device is based on the MySensors platform and it is built with the new Mini-BT-Pcb board.

As many other commercial device it uses a Reed switch and a magnet to detect the opening of a door or window.

The cost of the entire build is low (about 5€) and it can be used in many different cases like for example to detect the opening of a drawer or fridge door.

RFM69 (868 Mhz) and NRF24L01 (2.4 Ghz) radio modules are both supported and the behavior of the 4 LEDs can be configured in the firmware.

The expected battery life with a single CR2032 coin cell is more than 1 year.

Visit the dedicated wiki page to build yourself one of this sensor.