Smart Drawer Locks - Help Needed!

I’m hoping for some advice from the community for an idea I’ve been thinking about for a long time. What I need to do is find a way to lock and unlock a chest of drawers using SmartThings. My original idea was to use a solenoid latch (something like this) on each drawer and just plug them all into a smart plug. Turn power on to the plug, the drawers unlock. Turn power off and the latches release, locking the drawers again.

The first problem that I have is (I’m embarrassed to admit this) I have no idea how to connect eight of those latches into one regular plug. Does anyone have any experience with something like this or recommendations on how something like this should be powered?

The second problem is, based on my reading, solenoid latches like that are only meant to be powered for a few seconds at a time, meaning we would have to unlock the drawers every single time we open one. Ideally, I’d like to unlock the drawers long enough to put away a load of laundry or get the toddler dressed.

I’m wondering if anyone has tried something like this already, or has some tips on how I could get it going? Is there a better option than the solenoid latch? Maybe a better control mechanism than a smart plug (raspberry pi? arduino? other?)?

Any and all advice is appreciated!

Seems like a long way around for babyproofing, but a fun project if you’ve got the time and cash to do it…

A simple and clean way to do it would be to put a terminal strip in a project box - something like this, but you can probably find the individual parts cheaper if you look around. You would terminate each wire with a ring terminal and make short jumpers to join individual strips - max 2 rings per terminal. 8 poles means you can use 4 poles for hot and 4 for neutral, with input and jumpers on the left side and 2 outputs each screw on the right side.

You can use a pull solenoid so that it unlocks when you turn on the plug, instead of locking, and your drawers are “fail secure”, aka if the power goes out they’ll stay locked.

In my quick Amazon search, there weren’t many 120VAC pull solenoids available, so you might be able to skip the terminal block by using an AC-DC power supply with multiple outputs integrated.

There are some existing threads on this topic:

Looking for a way to lock a cabinet
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Simple Lock or catch - where to find basic lock - no keypad etc (newby)
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ZWave or Zigbee Controller for Linear Actuators? (Automated A/V Cabinet project)

All of that said, There are hundreds of locking cabinets on the market already. Most of them aren’t smart, but do they really have to be? Get one with a combination and you can share it if desired. Some of them are smart which is a whole other conversation, but I wouldn’t think the cost is justified in a typical home.

It’s true that you can basically use an electric strike method with fail closed, but I wouldn’t trust smartthings to be reliable enough to always open it when I wanted it opened. So I suppose it depends on how much of an inconvenience that would be.

I have friends with family members either on the autism spectrum or with various types of dementia who have added locking cabinets to their homes, but I can’t think of anybody who required automations for them.

But different things work for different people. Yale has a product in development which will be a $79 cabinet lock that works with their august system, but it’s not available yet. Back in January they had announced it for “spring 2020,“ but I don’t know if their supply chain has been affected by the coronavirus or not. It looks like a nice product, though. :sunglasses:

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Not a SmartThings solution, but Ikea has NFC triggered locks. Hold your phone or key card to it and it will lock/unlock

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That’s exactly the idea. There’s 1,001 baby proof products out there that can be bought for $20 and 20 minutes of install time. I’m looking for a project to keep my mind occupied while sitting at home, social distancing for God knows how long.

Forgive my ignorance, but what’s the difference between this and the latch I linked to in my first post? Is that latch not also a pull solenoid? My problem is I would want it to be energized for ~5 minutes at a time. Would the item you linked be ok to leave “on”/unlocked for that long?

I really appreciate your reply and advice!

My mistake, I missed the link in the text. For extended periods of activation, you would want a “continuous duty” rated solenoid.