Need a sensor recommendation for a metal door

Hi folks… So i need a door sensor… However the normal sensors that use magnets etc dont work on my door frame… its a giant Iron door, and the frames dont work for that type of sensor.
Also, the accelerometer in it doesnt trigger easily enough. it takes a fast door open to trigger… I want a fairly sensitive (or tuneable) acceleration based sensor.
please advise. thanks

Have you looked at plunger sensors? You would need to recess it in the doorframe I would assume as the door is iron … hope the frame is wood…

Dont have a link handy but google zwave plunger contact sensor should work

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These ones, but they don’t have stellar reviews: https://www.amazon.com/dp/B01KQDIUAW

What about this… I have one and they are rather compact so this might suit your needs. Certainly not as much drilling required…and Z Wave Plus (and a 10 year battery life…or so they claim).

John and Nhaley… good options, but the hinges are iron and large as well and I cant drill in to the wood frame… I mean i can but the trim work is too beautiful, i wont be doing that… looking at the other now.

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I cant really tell if its JUSt this strip, or if its the other bigger bulkier thing too… if its just the strip, i may be able to make that work.

The contact sensor is just the strip (the other item is a bonus freebie). The sensor itself is very thin.

Here’s their official website…

That’s still a magnetic sensor even though it’s a different form, Unfortunately it’s not going to work on the metal door.

You can use the traditional box sensor if you lift it up off the metal surface and put it on a plastic or maybe a wooden block. But a lot of people don’t like the look of that. See the following thread for discussion of metal gates, which is a similar issue (this is a clickable link)

I do like the accelerometer idea if you’re OK with the looks and you can keep the sensor from getting smashed against the wall.

i dont mind putting an accelerometer on my door, but the sensor i have https://shop.smartthings.com/products/samsung-smartthings-multipurpose-sensor doesnt seem to be nearly sensitive enough… you can open the door slowly and it wont trip… it only trips if you open the door fast.
So if there is a different accelerometer one that is sensitive im all game

You might try this hinge pin sensor (says it works with SmartThings) $39:

John

wont work… wont fit in the pin spot, as its a giant iron door. thank you though

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There are a lot of accelerometers, I’m just trying to think of one that will work easily with SmartThings Besides the multisensor.

Xiaomi makes a cube, but I have no idea how sensitive it is. it’s very inexpensive, and there are some community members using it, but so far people have only reported using it as a light scene selector, I just don’t know if it’ll adapt to the swinging door use case. But at only $15, it might be worth a try.

https://www.gearbest.com/living-appliances/pp_364494.html

The Fibaro multisensor, the one that looks like an eyeball, has a tamper sensor based on an accelerometer and there is a configurable parameter that lets you use it to get position in space. Really well engineered device, but much more expensive. But again I don’t know how sensitive it is or if anyone’s written a device type handler to expose that option.

@TheSmartestHouse is an authorized Fibaro dealer, they may have heard if anyone is using the tamper alarm for similar use case.

Back to the original problem… If the door is normally kept closed one thing that some offices do is to put a very strong magnet piece on the wall and the sensor piece on the door in such a way that once the door is open about 6 inches, the magnet is strong enough to pull the reed inside the sensor into position. But because the magnet is normally kept away from the metal door, you don’t have the usual problem of the magnet magnetizing the metal of the door itself, eventually causing false readings.

This works best with doors that have a doorstop on the wall as well so the sensor pieces can’t get crushed by the door opening.

In your typical door sensor, the smaller piece is just a magnet in a fancy box. You can replace it with any other magnet, including one that is much stronger or weaker if you want to try to adjust the detection distance.

So that is something which is done in commercial buildings, move the magnet off the metal door all together but is a much stronger magnet so you can cover about a 3" Gap rather than the typical half-inch gap. You’re still keeping it away from the metal door, but you should catch the open event before it’s wide enough to let a person through. Just another option to consider if it works aesthetically for you.

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maybe ill try that… i have some neodymium magnets that may work… good idea.

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that did the trick… places a small neo magnet on the wood trip. moved the main sensor as far over on the door as i could… voila… problem solved… thank you so much for the suggestion.

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