Wider gap magnetic closure sensor?

I’m trying to hook up a sensor to a sloppy/loose mechanical roll-up security door on a commercial location. I’ve tried the usual ST multipurpose sensor but the magnetic range isn’t far enough: if I put the two parts close enough to trigger, the wiggle in the door inevitably knocks things off after just a few cycles, but if I put them far enough to consistently stay in place they won’t trigger.

Is there a magnetic sensor that has significantly longer range? I’m thinking maybe something that loses the magnets and instead uses RFID/NFC type ranges of ~1 meter would be perfect.

Seems like a stronger or more secure mounting method would do the trick?..

1 Like

I’d say your best bet would be to find a different sort of (dumb) switch and hook it up to a smart door sensor that has a connection for an external contact. I’ve used this Ecolink door sensor in similar situations.

As far as the dumb switch to actually mount on the door, a quick google search shows this magnetic option which will work up to two inches away. Or perhaps one of these mounted next to the door with a paddle attached to the door to hit it?


You’ve gotten good suggestions. We’ve discussed this in the past With regard to gates that have a wide gap when you close them. And, yes, the usual answer is to get a nonnetworked gate closure device and just connect it to one of Networked sensors.

The following device is pretty popular for the nonnetworked part:

(edited to note that this is the same device that @jh0 already linked to.)

Before looking into those, though, Also remember that the magnet piece of a standard networked open/close sensor is literally just a magnet In a pretty case. You can swap it out for any other magnet, including one which is stronger, and often that’s enough to solve the kind of gap problem that you’re describing. :sunglasses:

I use very powerful magnets out of old hard disk drives attached to my garage doors. These then trigger inexpensive magnetic reed switches mounted fairly far away from the actual door. These work great for my application.


Very cool! going to open old HD just for the strong magnets.

Awesome ideas everyone! In my case the biggest problem is the outdoor physical connection and I think https://www.amazon.com/gp/product/B005DJLILI/ is the perfect answer. Next question then: what’s the best way to hook this to a smart sensor? Do I bust open a ST Multipurpose and find some wires inside? I’m traveling and don’t have any handy to look at (I’d like to order all this so it’s waiting when I get home!!)

The door is burly enough that more secure mounting just destroys the plastic sensor, unfortunately. I tried that :frowning:

This guy has a pair of screw terminals inside the housing that you can connect to the external switch you linked, no funny modification required except possibly making a hole in the housing to route the wires.


Perfect! I just ordered some. Thanks for the ideas everyone.

1 Like

The GoControl contact sensors also have externals, this kit has 2 contact sensors and 1 motion/temperature sensor for $43…

© 2019 SmartThings, Inc. All Rights Reserved. Terms of Use | Privacy Policy

SmartThings; SmartApps®; Physical Graph; Hello, Home; and Hello, Smart Home are all trademarks of the SmartThings, Inc.