Multipurpose sensor used to detect door knocks no longer working correctly

Several months ago I bought a multipurpose sensor to detect door open and also door knock. The open/close function works flawlessly and for the first few weeks the door knock option worked as planned. Every time it pinged me that there was a door knock, I immediately looked at our home security cameras and there was someone at our front door. I was able to watch them as they left if we weren’t home. Lately it seems to have gotten extremely sensitive and gives us false alarms at about 3 or 4 a day. Not sure whats going on or how to fix. Anyone have suggestions?

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sad when things decay.

Usually to improve the alert signal you have to add sensors to perform “cross zoning” or similar, to double-check. Another/redundant sensor or input must ALSO alert in addition to your knock sensor in near-time in order to send the notification to user. Like a pressure mat, or camera motion signal, or PIR motion signal.

Seems like knock sensor is not so foolproof anyway, what if they ring the doorbell instead? The bigname video doorbell systems seem to have some decent signal processing that reduce false alerts. They also can make it easy to reply that you are busy cleaning your Ruger and ask what they want.

Mine also started with false alerts…anyone have an answer of why it’s doing that?

My alerts to even when there is not a knock also, although I presumed it was due to high winds moving the door/shaking just enough to cause this. Don’t know what it is, I suppose.

Funny, I just assumed it was a wind thing, but I’ve been getting these for the last few days as well.

my multi-purpose sensors all randomly give false vibration alerts… sometimes it just goes off for no reason that I pretty much disabled all the vibration and strictly use them as temp and open/close

I have noticed this issue too and after several testing scenarios I have determined that my vibration sensors goes off every time I go to the Multipurpose sensor and tap the refresh button or when I go to the Recently tab and pull to refresh. There is some new bug that occurred with one of the recent updates that is causing this as it didn’t happen before about a week ago.

The other odd behavior I am seeing with the multipurpose sensor is that I am seeing a long delay between the Active and Inactive states. Previously, it would show Inactive within the same minute or a minute after it was active.

I had two instances (last night/this morning) where it took about an hour to show the Inactive state after it was Active.

This behavior (phantom activity on the multisensor) appears to be getting worse for me. Are others having this problem?

Hate that everyone here is having the same problem as me but am glad you posted about it. Hoping Smartthings Tech support will add their opinion and give us some guidance. I love the idea of the function of the vibration sensor and paid more fore the multi sponsor as apposed to a basic open/close sensor for this function. I have since turned the alert function off as I was getting up to 10 false alarms a day.

Hey guys. This sounds interesting…what smartapp are you using with the sensor? I’ve not used one to detect a knock before.

I’m using ‘Notify Me When’ to notify me when acceleration is detected on the multipurpose sensor I’m interested in.

Just as an alternative idea, I have my multi sensor next to my door bell ringer. Any time someone pushes the bell I push an alert with a rule. Works every time with the Vibration of the door bell chime

That’s pretty cool BoSTon. I built a light controller out of one of those, …the guy with the wood cube that put the multi-sensor inside gave me the idea, he controlled routines with it. I built something different, I used a wood star and of course the math is different for that than the cube.

One thing I noticed while I was testing the star is that the xyz coordinates wiggled, even after the device was set still the sensor would occasionally send tiny xyz adjustments. I had to build in a tolerance range so x-100 to x+100 (pick a tolerance for all 3 directions) where thing would be considered not moved. I looked through the code for the “notify me when” program and it didn’t have any accommodation for wiggle – it looks like if the sensor reported new coordinates it activates no matter how small the change is.

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I ended up deleting and re-pairing the sensor and it’s now been about 20 hours without a phantom vibration. Might be worth a shot for others who had this issue.

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Well, that was shortlived. I am getting phantom activity again today.

When I contacted support, their response was that it might be the wind or some other movement because the device is so sensitive. I don’t believe that’s true since a) it didn’t start happening until last week and nothing substantial has changed and b) I can actually move the door it’s attached to slightly and not set it off, so the likelihood that this due to sensitivity seems pretty low.

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Try this…create this smartApp and attach it to your multi-sensor in the setup…then just watch the debug log for changes and testing.

I am also getting phantom active alerts. I replaced the sensor it was happening on and it stopped, so definitely not wind in my case. It’s especially annoying when it sets off the alarm. I have a 2nd that is doing it now (out of 9 total) I am going to experiment with it, and remove it completely from the door and put it on the concrete floor under the ST hub.

One more who was getting phantom door knock alerts. Using multi sensor and door knocker app. Haven’t had any false alerts in the last week or two, but last month they happened pretty frequently.

Also getting phantom door knocks. Had to disable as it was giving alerts non stop. I noticed that if you click refresh from the app on the multi sensor, it causes a door knock.