3d Printer Safety - need a smartapp

Hey guys, I’m fairly new to ST, so I may be missing something blatantly obvious and right in front of my face.

I have setup a 3d printer, which I’m enjoying immensely, however there are some inherent fire hazards to deal with. I’ve outlined a 3 phase safety plan.

  1. Smoke/Fire Alarm directly above the printer connected to ST and tested notification features are working

  2. ST compatible power wall outlet and temp sensor.

  3. Updated printer firmware to prevent thermal run-aways.

I need help with phase 2.

How do i configure ST’s to monitor the temp sensor (regardless of modes) and shutoff the power to the printer via the smart power outlet?

I cannot seem to find a default app/smart-app that will work, or I’m unsure how to configure one to work.

Can you guys point me in the right direction?

There are a number of different ways to do this, and certainly WebCore could, but I would strongly urge you to reconsider using SmartThings for this particular use case. The consequence of the system failing are just too severe.

Note that the company itself advises against using SmartThings for this kind of purpose. From the official product usage guidelines:

Data accuracy and consistency from SmartThings sensors, including those provided by SmartThings directly, resold by SmartThings, or supported by SmartThings, is not guaranteed. Therefore, you should not rely on that data for any use that impacts health, safety, security, property or financial interests. For example, because temperature readings may vary significantly from reading to reading on an individual device, between devices, or over time, those readings should not be used to control heating and cooling in environments where food spoilage, health risks, or damage to physical goods could occur.
In all cases, SmartThings does its best to interpret and maintain the state of these devices (including by querying for current data), but this is not intended as a replacement for direct, physical verification in situations where the true state of a device may have an impact on health, safety, security, property or financial interests. For example, you should not assume that a curling iron (which may cause a fire if left on too long) is actually off without physically verifying the state.

SmartThings is very useful for convenience notifications, but when it comes to fire safety, I would look for other alternatives.

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Thank you, I understand it won’t be foolproof, however I cannot think of any other alternatives.

Since safety is planned in layers, I believe I will be ok as I will still have the firmware update and smoke detector independent from ST.

I also don’t plan on running the printer when away from home, but would like to use it overnight.

If you can think of an alternative that doesn’t cost $1000 for a fireproof safe, I’m all ears.

Get a smoke alarm that sends notifications of the type you want. There are a number of these. That way you’ll get the alert.

Go to your local Home Depot and tell them you want a plug that turns off when a specific temperature is exceeded. There are a lot of these, they usually cost about $30. People use them in greenhouses or to control space heaters. Reliable and cheap. They won’t be networked with anything else, but for fire safety you don’t really need that.

These are also sold for controlling cooking equipment with an attached temperature probe. Same price range, same idea. Turn the power off when the heat gets to specific point. But you might prefer to position the probe so you catch the temperature right next to the printer.

Here’s a typical one:


Awesome, thank you so much!

Not sure 10A is enough, I’ll have to research… But this gets me going in the right direction.

Thanks again.

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Good point. The ones with the temperature probes for cooking appliances come in a much wider range of load then the ones that are intended for space heaters and air conditioners. There are some heavy duty cooking ones which run barbecues and stuff. But you’ll definitely want to check the specs on anything you’re considering.

The point is just that there are quite a few plugs with built in thermostats that control the power to a device plugged into them so that part of the equation is solvable at a pretty low cost. :sunglasses:

This one is popular for air-conditioners and goes up to 15 A. But again there are a whole bunch of these so you just need to find one that does exactly what you want and matches the printer specs.


Here’s the kill-a-watt meter while I’m printing… The highest I saw was 2A, so I think the first link you posted will work fine.

Thanks again for the brilliant idea!

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