DIY Door/Window Sensor using MQTT

Hey everyone!

years ago I developed a ESP8266 based door/window sensor that runs on battery. The whole system is set up to last up to 2 years on one CR123A battery (yes unusual, but fitted perfectly for my needs).

I designed my own circuit and wrote the necessary SW. The Box is meant to be 3D printed. I made multiple versions depending on the place it is supposed to go (more or less space)

I promised to share the project here back then, but never got around to it.

If anyone is interested, you can find everything across 3 repos on github:

Here a couple pics to give you an impression:


Feel free to ask me any questions regarding this project!


Hi !

cool thing! have also created an own windowsensor, which is running since almost a year… as battery I’m using a LiFePo AA Cell.
Unfortunately the ESP01 does not have an analog pin (in fact it has, but not broken out and just 0-1V), so low voltage alarm is not really possible without additional hw, or ESP modification… ESP.getVcc() does the job… :smiley:

I’ve included also an OR gateway to have only one device for multiple window sensors…
e.g. if you have a double window, imho it does not matter which one is open, but one/multiple is/are open…
of cause it would also be possible to just squeez multiple cables into the terminal…