Mains Powering SmartThings Sensors (Basic Guide)

I recently got into the home automation thing with ST and im enjoying it.

I looked around for a while and didn’t find much information on this (as basically no products) so figured I would share what I did in case it is helpful to others.

Long story short I love the ST idea / concept but I cant stand battery powered devices, im lazy and I want things to work reliably and constantly without any input.

So see the below imgur link for lots of photos for wiring up a few types of sensors for mains power.

Its frightfully easy, all you need is :

A sensor
Wire
Soldering Iron & Solder
Buck converters (any should suffice, ebay, Amazon, currant draw on these things is negligible)
Terminal Blocks (ebay)
12v Power Supplies (Buy Meanwell PSU`s, they are highly regarded and I dont risk random Chinese stuff in the house)
Other things.

Short version :

Mains > 12V Power Supply > 12v Out > Buck Converter > 3v Out > Sensor

Disclaimer :

Try any of this at your own risk, im not responsible for you or your hardware, if in doubt get a professional in, especially where mains voltage & wiring is concerned.

Quite a few community members have posted project reports on similar projects in the past. :sunglasses:

You can find these by going to the quick browse lists in the community-created wiki, going to the projects reports section near the bottom of the page, and choosing the “power” list.

https://thingsthataresmart.wiki/index.php?title=How_to_Quick_Browse_the_Community-Created_SmartApps_Forum_Section

Just be aware, as you note, that any approach that requires soldering to the device internals will void the warranty on the device. That’s why some people prefer to use a dummy battery approach. :zap:

Also just a note that one reason people choose battery over mains for some specific devices is so that the device will continue to work if the power goes out. :wink:

Obviously that doesn’t fit a use case where a motion sensor triggers a mains powered light. But if you want the sensor to trip a siren on a shed, for example, battery power might be desirable. :rotating_light:

I had one friend who got a new pack of 6 sensors, soldered everything, then realized that two of the locations where he wanted to use them were better suited to batteries. :face_with_raised_eyebrow: (He had fun soldering, though.)

Sadly failed to see any of these, if its not in a Google result does it even exist?

Hopefully this will of of help to somebody.

That wiki link has some very interesting things on it I will review.

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