Open/Close sensors... how accurate are they?

So I’m looking for anyone who has experience with these… how accurate are the Open/Close sensors?  If I have one on my house door, does my door have to be completely closed in order for it to register closed?  Or can it be mostly close and show as closed?

I know the sensor will tell me is someone opens the door, but will it be able to tell the difference between completely closed or almost closed?

The open/close functionality of the SmartSense multi-is the typical magnet based design. So one part goes on the door frame, one goes on the door. When they are lined up, the magnet is connected and the door is closed. When you open the door and move the magnet away, the door is open.


So the door is either opened or closed.

@Chris - there is some inaccuracy in that it doesn’t have to line up perfectly - it could register as closed if the door was open 1/2 inch maybe… this is also depending how you mount it - when you get yours play with them and slowly open them different directions. If you pull it off (can’t really describe by text well…) but if you pull it off directly away (not sliding it off an edge) it is like 1/4 or so.

The sensor is registered by the presence of a magnet - which is a “field” being detected - a truly accurate system would require some circuit with direct contacts that would be connected or broken.


The magnet type I use are a fix location type so if the door is shut tightly this will be your origin. I think you may be more worried about if your door is fully closed and latched correct? If the door is out of the strike plate the SmartSense would open and the Smartapp would trigger. Play around with your doors now to see movement from the origin away from the strike plate .

Yeah, this is kinda what I thought it would be like.   In other words it’s entirely possible to give a “false positive”  That is… the door is close enough that the sensor registers closed, but the door isn’t closed enough that the latch isn’t in the strike plate… meaning someone could push the door and it would open.

I thought about mounting the sensor between my screen door and my main door… this would probably allow me to separate the sensor enough that it’s only when the door is fully closed that it would be close enough to trip the sensor.  The major downside is that the sensor is “outside” and someone trying to break in could relatively easily fool the sensor.

Of course, even a contact sensor could be fooled by a door that is almost all the way, but not quite perfect.  The only way to know for sure would be to have a sensor inside the strike plate that senses if the latch is inside the strike plate or not.  I don’t think my Kwikset has the ability to know if the latch is all the way extended or not.

The multi sensor can also do movement sensing like vibration or acceleration. So if you’re in away mode, if the sensor is on the door and it swings open, you could sense that movement.

I put the sensor on the top of the jamb and the magnet on the door. Move the magnet as far away until just out of range

My issue is the need for a reset time. If I get an alert for the door being open, I want to be able to set the time interval for the next alert; i.e. Open the door and grab something, alert. Within 3 minutes, open again, no alert. Anyone figure this out?

I’m also playing around with some rare earth magnets. I pulled the magnet out of the housing – it is 1/5 the size of that housing – and put up temporarily with blutak. Some stronger magnets may allow me to play around with where I mount things.

We also need an App to note that the sensor is now closed. There are some that notify that it has been opened but would be nice to know later that it has been closed.