Iris Motion Sensor (2nd gen, 3326-L)


(Jason "The Enabler" as deemed so by @Smart) #323

If my memory serves me correctly, which it probably doesn’t… but I believe ST see a 2.7 as the low end of the battery life.

Maybe @JDRoberts remembers what that range is.

(Jason "The Enabler" as deemed so by @Smart) #324

I had a battery reading 1% yesterday. I swapped it out and just threw it away. It was the original battery and was about 2 years old…

I hate this battery issue for everyone, those things are not cheap at all.

(Robert M) #325

On my multimeter, a new CR2 battery like the one I use in my Iris sensors registers around 3.2V (with my multimeter set to 20V DC). By the time it gets close to 3.0, it’s practically dead. I don’t recall what exact values correspond to ST’s battery percentage reporting, but lithium batteries don’t decline in voltage in a linear fashion–see, for example: This makes it difficult for the DTH to predict remaining capacity based on voltage, especially since it plateaus for a bit after a slight initial dropoff and a sharp final dropoff if it’s even still usable at that point. I’d be hesitant to rely on ST’s reporting given this difficulty.

(My multimeter might be reading this all a bit high; I’m not sure how well calibrated it is for these voltages—certainly appears to be a bit higher new than on the Energizer chart above—so if you have one you may want to test when new and “dead” to compare.)

(Seth Daniel) #326

Does anyone know if this works for the 3326-L2? These are currently on sale at Lowe’s for $15, and I’d like to buy several, but I want to ensure they work with SmartThings first.

(Jimmy) #327

If what works? They work out of the box now.

(Seth Daniel) #328

This thread seems to be about the 3326-L model.

There is also a 3326-L2 model, which I don’t see mentioned in many places.

I’m currions if the -L2 works in addition to the -L. I’m guessing the answer is yes, since it seems to be a new version of the same sensor, but I’m not sure if there’s an important difference for SmartThings compatibility.

(Jimmy) #329

They’re the same sensor, only difference is the packaging


Well, a couple days ago had another one go into meltdown mode and start registering false motion every minute or so. Replaced the battery but then sadly another for the waste bin.

EDIT: Did it again last night (couple days past a month) and killed the battery, so time to order something else. Given how highly people rate these, I wonder why mine are having so much trouble. I did find my Google WiFi causing problems for a Bosch motion sensor, but that was when it was super close. When I moved it away it was fine. This Iris one isn’t that close.

(MarkTr) #331

I just got around to replacing the battery in a problem sensor, taking notes this time, and it died after 6 days. I read up on a few of the recent threads, including one about updating Iris device firmware via Iris hub, which prompted me to check my sensors’ firmware in the ST IDE.

I have 5 sensors, all purchased within a 1-2 month period (when Lowes had them on clearance last fall). One of them eats batteries. All are running the same firmware, 0x1C005310. However, 4 of them have “N/A” for “last updated”, presumably meaning it shipped with this firmware. The problem sensor says it was last updated 9/5/18 (same day it was added to the hub).

I think I’ve seen the suggestion before that the battery problem is linked to firmware, but my interpretation of this data point is that the problem isn’t the firmware release, but either ST’s copy of that firmware or their update process. I don’t think I’ve previously seen the blame placed there, so I wanted to throw it out there and see if anyone who has both good and bad sensors finds the same thing.

Edited to add: even if this could be confirmed as the cause, I can’t imagine anything could/would be done to recover those sensors - it’s not likely that Iris is releasing new firmware (RIP). Since the bad sensors already have the target version, would it even be possible to overwrite it with a new “good” version? And if it was, would ST bother to devote resources to supporting an obsolete device? @tpmanley, would you care to comment on the technical side?

(Tom Manley) #332

@MarkTr, the FW update process in Zigbee is standardized so I don’t expect that to be the issue. The FW we release is provided by the manufacturer so it should be the same thing as anything they release in a manufactured product, although we have no way to confirm that. Have you tried factory resetting the device and joining it again (no need to remove from your SmartThings account before you do this)? I’ve seen cases where the new FW caused excessive battery drain that would be fixed by a factory reset. To my knowledge we’ve always caught and corrected those issues before they were released but it’s worth a shot. If that doesn’t work you can PM me your info and I can take a look to see if I can determine what’s causing the battery drain.


If you guys get anywhere, please report back. I had one move into the <1 week dead category and after 3 batteries I threw it away. I have another that is now in the ~2 month dead range so watching that one. I had another one go into the <2 week dead range but was under return window so got a new one.

(MarkTr) #334

Thanks Tom! I reset the sensor last night (with a new battery) and it reported 89% after about half a day. I’ll see where it is this evening and send you a message if it’s still dropping.

(MarkTr) #335

Dead after ~5 days. Sending you a message Tom…