No-code, child safe mains switch (using tinker and ifttt), or: how I control my christmas tree

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I set out to develop a switch for mains devices that i could build and use from my phone without having to program anything. To achieve this, I attached a relay to a Photon to make a switch for any device that uses mains power. I put everything in one of those boxes also used for clock-switches. A usb charger is also hidden in the same enclosure, powering the photon. The photon runs the out-of-the-box Tinker firmware, so no programming of the photon. Tinker is reached from my phone using the DO app from IFTTT, so also no online programming, making this a nice IoT project to introduce people that really, really do not like to code (or have very cold feet).

This provides a nice, child save, device that I can use to switch on and off devices in my house, in particular my christmas tree lights.
Video: https://www.youtube.com/watch?v=l4wJQ-Dm66k

I added it to the "tech" contest running at Instructables, so if you like it, vote for me here: http://www.instructables.com/id/Christmas-Tree-Controlled-From-Phone-No-Coding-Req/
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First of all, this is a neat project. Not that complicated, and actually useful, so yeah, that’s nice!
But as much as I like this project, it also scares me.
The only warning in there is not to strip wires with your teeth, and that was jokingly. That’s great, but you failed to mention one other small detail, that is: mains power can, and will, KILL you if handled inadequately. That is something you cannot ignore, and should put on the top and bottom as a proper imposible-to-miss warning. It’s a bit dubious to call a project ‘child safe’ if it might seriously harm, or potentially KILL the person building it, isn’t it? I wouldn’t want to be responsible for that.
The amount of pictures you’ve includes is also very sparse. Should you want to ensure a higher level of safety, I’d recommend including as many and as detailed pictures of the wiring as possible. That won’t prevent any problems, but might decrease them. Assuming people know how to hook up mains safely, is not an assumption you want to be making.
Then there’s the housing; due to lack of proper explaination and images, it’s impossible to tell how you’ve housed it. Saying “make sure components do no touch the mains connection” is an inadequate warning, if not an extremely dangerous one! That implies that it’s alright if it looks okay~ish. That’s the exact thing that gets people hurt, which is something I wouldn’t want to be responsible for.
There’s a reason power supplies have to ensure proper insulating clearances and materials to ensure a certain level of safety. Apple chargers might be more expensive, but their design ensures you don’t end up in the news as ‘person electrocuted due to poor power supply’. Again, you don’t want that.

To summarize; neat project, but not safe (at all). I wouldn’t call it safe for anyone, let alone for children. Unless you’ve ensured proper warning, I wouldn’t recommend people trying this. So please, please edit the project to include warnings! Reacting with “what he said” does not counts as an adequate warning!

This is not to bash your project in any way, because it’s a genuinely nice project. I just think you’ve thought of safety a bit to easily, assuming people know how to apply proper and safe practise, which is something you cannot, and should not do if it concerns potentially life-threatening issues.

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Hi @Moors7,

I get where you coming from. The “child safe” is the result, not building the thing, I could have made that clearer. Everything related to mains is housed in the enclosure, so children walking around the house can not electrocute themself. You are absolutly right that people should be careful when working with mains power. However, since you only power this project when it is enclosed, I think you over estimate the danger a bit. If soldered badly, one might blow a fuse, but will not electrocute onesself.

Rolf

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This assumes, that people do pay enough attention to the importance of the quality of the enclosure when copying your project.
So a warning for anybody who intends to copy this would definetly not hurt.
And bad soldering might not only result in blowing a fuse. If you have "frazzling" connections you might not be so lucky to trigger a fuse but actually cause fire.

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Will all due respect: no. There's no such thing as overestimating danger when working with mains power. Especially when you're trying to have people do that over the Internet. Trained and well educated electricians are getting electrocuted on a daily bases. Where do you get the assumption from that 'regular' folks are keen enough to make sure they don't without any proper experience, and thoughtful consideration of potential danger? The fact that you call it safe, without making the necessary warnings is rather misleading, if you'd ask me.
Saying it's safe because you don't power it until it's housed is like saying making an IED is safe for everyone since it should only blow when intended. It should. That doesn't mean that it will. It also doesn't mean people know safe practice for dealing with things they've got no experience with. Sure, I could follow a youtube video claiming "if you do this, it's going to be really awesome!", but that doesn't ensure I don't hurt myself in the process. Give warnings where they are due.
And much like @ScruffR mentioned, the housing is a realistic fire hazard the way it currently is. There's no explanation of how you get all the electronics in there, let alone how you make sure they don't short each other out.

Or it might burn your house down. With you and your, apparently 'safe', children in it. And that's totally cool it that's a risk you're willing to take. But when publishing this openly, with the intent of people being able to replicate this, I think it'd be fair to include a proper warning.

Again, I'm not trying to talk your project down(!), but please included warnings. You can't have too many of them when working with potentially life threatening projects. I say 'potentially' because it shouldn't hurt anyone if handled properly. The main thing that worries me is that you defend your lack of warnings. What's the worst thing that could happen if you included them? Try to weigh that against what might happen if you don't. I'm not saying anything bad will happen, but why not take the extra step to help prevent it in the first place?

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