Anyone have issues with Iris V2 (3326-L) motion sensors dropping off / disconnecting?

I have four of these, and they always end up falling off the Zigbee mesh eventually. I have adequate Zigbee repeaters (I think), and as another data point my Third Reality Zigbee contact sensors on the complete opposite corner of the house from the hub function without issue. So does all my Hue Zigbee stuff.

I kinda remember this occasionally happening with SmartThings back in the day, too, with the Iris. Is it a known problem with the Iris sensors, or any way to make them more reliable? Other than that they are great little sensors but I am about ready to move on. Just curious if anyone has had a similar experience.

Which hub do you have, C7, C8? How many repeaters per battery operated Zigbee device? IIRC recommendation is five or six devices per repeater.

I do have intermittent problems w/my Iris v2 motion sensors since moving to the C8, but I am one of the "lucky few" who has had ongoing Zigbee issues on the C8. I can pair them back to the C8 but that doesn't guarantee they won't fall off again. I have a lot of them, 28 or so, and they were rock solid on my C7 before I migrated everything to the C8. I have a lot of Zigbee devices, just over 100.

I don't have a clear fix for keeping them on the C8, the main approach I'm taking now is if a Zigbee device falls off the C8, I'm moving it back to my C7 and sharing it to the C8 for automations via Hub Mesh. Partly hoping that reducing the Zigbee load on the C8 will help.


I only have one, but it has been rock solid for many, many years. I was first on Smartthings and now on Hubitat.

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Thanks for the info. I am on the C7 hub.

I have 5 Zigbee repeaters (all smart plugs). And 6 battery devices (4x Lowes Iris V2, and the 2x Third Reality contact sensors. So not very many devices :slight_smile:

I do have a fair amount of HUE lights, but those are all going through the HUE hub on their own mesh and connected to Hubitat via the LAN hub integration.

The latest Iris V2 to fall off is literally 6 ft from the hub, so one would think it would have a good signal.

I do have a router AP near the hub that is delivering 2.4 GhZ as well as 5 Ghz, so idk if that's an issue, but it's curious that the Iris devices are the only ones I have issues with. And when they stay connected, they work great!

I have 4 of them all paired to a C8 and I have had no issues with any.

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Yeah, the Iris are the bomb in terms of motion ever.

You could look at your 2.4GHz Wi-Fi channel vs. Zigbee may have seen this before. Best if you can move your Wi-Fi away from the Zigbee channel you're using (see the Zigbee Details page for your channel info. Usually easier to move the Wi-Fi channel than Zigbee, but really up to you.

You can use a mobile app like Wi-Fi Man (from Unifi) to scan Wi-Fi channels in your home and see what you (and your neighbors close enough to show up) are using for 2.4GHz.


I have 10 of the Iris V2 motion sensors. They have been flawless except for one that resides on my garage door that I have had to do a battery pull twice this year to get it working again. I have an Iris V2 contact sensor close to that location that occasionally gets stuck in the โ€œopenโ€ state and I have to open and close the door to fix it. Iโ€™m pretty sure it must be some rf interference, since itโ€™s been happening for years now, and only in this area, but there are too many potential suspects nearby (breaker box, washer, dryer, refrigerator x3, microwave, wifi oven) and not enough occurrences to figure it out.
So, what @danabw said may be helpful.

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Thanks @danabw @terminal3 @Equis @Ken_Fraleigh for the replies.

I will check my WiFi 2.4 GhZ channel(s), and also see if I can move the hub from that AP, although that will require pulling ethernet to a new location.

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Just in case my reply wasn't clear, you'll want to avoid your neighor's 2.4GHz channels as well as your own w/your Zigbee channel. All of of the Wi-Fi channels (yours and any neighbors close enough to register) should show up in whatever channel scanner you use.

Have fun investigating. :slight_smile:

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I have 23 of these on a C-7. I have no problems with them falling off at all - rock solid.

(The only issue I've had was when I used rechargeable CR-2s in them; when the battery got low they would drop off and require re-pairing. For this reason I use disposal CR-2s on the motion sensors, and rechargeable CR-2s on the Iris v2 contacts)

Have you gone into Settings->Zigbee Details on the current release and done a Zigbee "Scan Channels"? That is another source of possible interference, in addition to 2.4GHz WiFI.


Also.check the hue hub channel mine changed in its own once during reboot after an outage ffing up my hubitat

To OP - these Iris V2 Motions are some of the most reliably connected devices on two C5s using Ch20 on one and Ch25 on the other. Have retired one errant motion over the last couple of years.

To @jlv , what did you mean here, the act of an occasional channel scan ?

Referring to this on Settings>Zigbee Details ...or did I misunderstand your question?


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Well, that's what it's related to...but I was trying to understand how doing that would cause the OP ongoing interference probs. But I think I misunderstood his comment.

OK this provoked me to update one of my hubs to earlier than I would have otherwise....and low and behold some nice info-tools did appear.

And low and behold if neighbor WIFI channel selection wasn't enough to worry about, I now have to be concerned about somebody with Zigbee devices stomping on my mesh. The one device that showed up was on Ch 15 and isn't always there. Wonder if it's a new utility meter; never thought to notice if Pan IDs are like MAC addresses in any way (i.e. a manufacture associated range).

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LOL...yeah, the scan isn't dangerous,but the results may be to your free time as you search out who/what is using your Zigbee channel. :wink:


My zigbee scan lists a zigbee network from 2 years ago, that was on my C4 before I changed its channel. Not sure what is going on. And my extended PAN ID's make no sense

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i would think this means there is still one device that thinks it is on that old zigbee network and is still trying to communicate.. maybe an in wall switch somewhere ore something.

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Only C-8 seems to report the extended PAN ID's correctly; my C-3 and C-7 show extended PAN ID's with the byte order reversed.


I meant as @danabw pointed out, the new feature in 2.3.6 that does a scan looking for other nearby Zigbee networks, which might be causing interference.


I wondered about that. Something ebayed, not yet joined that has a battery in it. Humm.

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