I realized today that the most used “smart home” project I have done is both 100% battery powered and not connected to WiFi or the internet at all. I added a light to my dresser drawers that turns on when the drawer is opened and off when it is closed, just like the inside your refrigator. The idea is so I can grab clothes in the morning without waking up my spouse by turning a bright light on. It’s been working every time I open my dresser for over 18 months now. It is a very simple idea but I had never seen it done before, so here is a quick run-down of how I made it work.
Materials
- 9V battery
- 2-conductor wire, enough to run from the battery to each drawer
- a 12V LED or 2 for each drawer (I used these that I had leftover from another project)
- a micro limit switch for each drawer
Setup
It’s a very simple electrical circuit. You are quite literally just flipping a light switch. Still, it’s probably wise to wire up a proof of concept.
I used 12V LEDs but a 9V battery. This naturally brought the brightness of the LEDs down to a more manageable level without the need for some sort of brightness knob. The entire goal of this project was to keep it simple and not alter the exterior appearance of the dresser.