Open/Close Sensors Fall Off


(Eric) #1

A general question for others in northern climates. I have 150 devices or so, and a good number of these are contact sensors on doors and windows, etc. I mention the total devices to show I have a pretty solid mesh going on for zigbee and zwave with good amount of repeater devices.

All summer and fall they all work, never have much issue. Winter arrived and we didn’t look at windows for 3-4 months…and now I notice half of these zigbee sensors “fell off” and require me to reseat the battery to come back alive…so the battery is good as well.

Should we do some polling once every 3 days or so or something to ping these things back to life? I understood they would check in on their own once in a while, so I am completely unsure when they fell off. Or should I chalk it up to ST and their issues? Just wondering what others have for thoughts.

70 degree spring weather will get you looking at your windows again!


(Chris) #2

We have some projects in the works that should help you get a better idea of which devices might needs some help, but unfortunately I don’t really have a timeline for when this will be available.

Here’s something to try though:

Unplug your SmartThings Hub for 20 minutes and pull the batteries. After 20 minutes or so, your ZigBee devices will start re-optimizing themselves to the nearest parent device (repeater). Then power the Hub back and up and see if things are more reliable.

It’s also possible that you might have something causing interference around the 2.4GHz frequency band in these problem areas.


(Eric) #3

It literally one sensor stayed alive in one window, and the one on the window next to it (less than 3 ft) doesn’t work. Very odd. This happens around the house.

Am unsure how many are ST sensors yet vs PEQ sensors I have; I know I have 18 or so to visit. Since they are dead (not doing anything) I assume I need to pull batteries in each one.

I will try the the hub offline idea as I have reshuffled zigbee smart outlets (repeaters) several times this winter…the hub is V1 so no batteries. Still waiting for the migration tool or a response from VIP help for migrating to V2!


#4

Cold can affect battery efficiency, battery efficiency affects transmission range, it could be something as simple as that. :sunglasses: Often the process of replacing a battery or even just resetting one warms everything up enough to get things going again.

The strength of a mesh isn’t based on the total number of devices – – it’s based on the total number of repeaters and their position. Ideally you’ll have one repeater about every 40 feet for zigbee. If there are architectural barriers you may have to be more precise with placement. For example, in a cement house of the type often built in Asia or an adobe house like those in the American Southwest, you may need a repeater near every doorway so you can get signal to go around the walls since it can’t get through. Once the weather gets cold, you may need repeaters a little closer to the sensors. :snowman_with_snow: :snowflake:

As was suggested, Taking the hub off power for at least 15 minutes to force A network heal is always a good idea. A lot of commercial installations will do this once a month, or even once a week just as a maintenance step.

@johnconstantelo has some wellness check code which looks at the event logs to see how long it has been since a device checked in. That’s clever, because it doesn’t use up battery on the sensors since it doesn’t talk to them directly. After he shared it, several other community members worked on smart apps to check individual devices. This thread is worth looking at. :sunglasses:


(Eric) #5

I have lots of zigbee repeaters as I mentioned…and grabbed that app last week which is how I know there is that many off.

But it doesn’t sound like from the responses that polling is an answer.

The cold is interesting angle although so random for which devices fell off so makes it plausible. I would expect devices that get to about 55 degrees on their readings on a window pane to still work though, you know?

The healing monthly is interesting…I always feel like when I do that heal things do not all come back well so I get nervous its going to give me more work to do. :slight_smile:

So I will skip polling them for now maybe. Don’t need to add load to ST. Gonna run a heal tonight and run around and change batteries and hope for the best ongoing.

Thanks for the feedback, helpful as always to verify approach.


(Pizzinini) #6

Have you looked at this. Maybe this app can help you with polling or better diagnose the problem.