Light not turning completely off


Ok, guess that's not a good test. Since 2.5VAC is pretty normal for floating voltage and most lightly you will get weird reading on the load terminal of the switch and neutral. My fault.
Couple other things you can do. Measure voltage between neutral and ground. It should be less than 1VAC. More than that means your neutral or ground is not good.
Measure between load and line of the switch when it's ON. Should be 0VAC. anything more than that is a bad switch.
I highly suspect you LED is too sensitive due to all your wiring bundles are close together causing higher floating voltage.


Hi there,
I'm new here but just googled this thread which is interesting to me since I've experienced similar issue.
In my case it was an electronic switch working as wireless controller which was installed in fan canopy.
So, do you have a simple circuit with light and fan ( separate switches ) ?
Are you sure that the load for z-wave switch are directly the bulbs ?
If yes, that would be strange indeed since I think there are relays built in the zooz switches ( I can hear the click ) and I have nothing but voltage - no voltage.
Measuring the voltage on load is a good idea, however maybe it would be worthy disconnect the load from zooz and check voltage first on load of switch and then on wire coming from bulbs.
Just to be sure from where it is coming....


I mentioned the remote controller above which is the same as you mention - the wireless controller in the canopy. In my case, the wireless controller "fixed" the issue. Originally I had the light and the fan direct wired, each on its own switch. This is where I experienced the problem. Once I put the wireless controller in the canopy, just connected to the light, I no longer have the issue. This is all new construction in my workshop, and I did all the wiring myself so I'm sure of the setup. I did check the load terminal with nothing hooked up, and there wasn't voltage as expected, so I'm pretty sure it is just the sensitivity with the light. So:

Powerline > switch > light = light not turning off

Powerline > switch > wireless controller > light = light turns off fine.



What driver did you use for the Zen27?

I just picked up five Zen26 switches to use in some circuits where I don't need dimming, and the first one I installed added as an unknown device. I changed it to a "generic zwave smart switch", and noticed it didn't change the state.

Changing it over to "generic zwave switch", seemed to do the trick, but it's strange, the zen21 I installed last week was detected correctly right out of the box!



We don't currently support the zen26 or zen27, they are overly chatty, especially the dimmer.
When and if Zooz ever fixes this we will support them.

Zooz power strip flooding zwave logs

Oh hm.. I’ve got the Zen27 running the Zooz Zen22 Dimmer v2 driver without any issues.


I didn't say it didn't work, I said it was overly chatty, if you fill a house with these you will have issues.


Thanks Mike. Guess I should have done my research before buying them! I'll run them as generic switches for now.



You're not following, it doesn't matter which driver you use, so use the one that works best, The dimmer is overly chatty, open a live logging window, enable debug logging, set the level to 5, then set it to 100 and you'll see what talking about.


Yeah, I understood. I've only got one on the network right now, so "filling the house" isn't an issue.

I can wait or simply replace them. I also quite believed you when you said they were chatty, but for curiosities sake I'll have a look. Mines the non-dimming I wonder how chatty it is....

My GE Smart Plug (with debug and text logging on) gives 2 info and 1 debug message on an "on" event.

The Zen26 (debug and text logging on) gives 3 info and 4 debug, for the same event.

So, more than twice the messages (although with debug off, it would be 2 & 3). Is this what you're referring to?



Yeah, exactly.


Thanks David!

Question: Do the device switches for Debug and Description text logging, actually turn the messages on or off, or do they simply hide/show them in the logs? If the latter, I reckon I see the problem, if the former, as long as I keep debug off, then I only get one or two messages per event (switch event), which would seem to be manageable.



The logging options controls live logging display, and do not affect the actual events produced.
The actual events under most circumstances are de duplicated at the database layer.
So for the zen26 switch it's not such a big deal, When turned on it will produce 2 on events, only one of which is actually written to the db and sent to subscribing apps.
The Zen27 dimmer on the other hand will produce multiple level reports whilst in transition from one level to another, each with an interim level value, all of these events are sent to the db and any apps using switch level.
A transition from 5 to 99 percent will produce 10 or more level reports.
No other dimmer I'm aware of does this, it cannot be changed or configured.
Sure special code could be included in the driver to ignore these, but why?, why should we spend time hacking up a driver for a device that in our opinion just behaves badly.


Do you know if the inovelli dimmers do this?


no they do not do this, no other dimmer does this.


Yeah, I can certainly see the problem with the Zen27. I agree, hubitat shouldn't include special code, as it sets a poor precedent, and increases the difficulting/overhead in maintaining the codebase.

This seems like something a developer at Zooz thought would be a good idea, and so here we are!

Zen27 dimmers are a no go for me. I've only got 3 dimmers presently, with a third on order, which will make 3 GE/Jascos and 1 Lutron Casetta.



Here is an answer I received from Zooz support regarding the issues raised by @mike.maxwell

Thanks for reaching out.

We understand the issue to be that the dimmers send extra reports during the dimming process itself. One of the other issues mentioned in the forum was that there are double status reports - this has already been addressed in the newer firmware. The dimming reports are also being addressed in the new firmware so if needed, you'll be able update the firmware or we can replace your dimmers with new ones with updated firmware. The new firmware file should be ready within a week.

Please let me know if you'd like us to reach out to you once the firmware is ready, and if you have any other questions!

I'm not sure how to update their firmware but at least it's a good news


Hi @anis_ber, we posted detailed instructions on how to update Zooz devices in the knowledge base. I can't post links here for some reason but if you google "How to Perform an OTA Firmware Update on Zooz Devices" it should be the first result.

Thanks for pointing our attention to this thread. We're still on the first production run with these devices so we haven't manufactured any new dimmers or on/off switches ever since we learned about the issue from the Hubitat team. We're testing the new firmware now and once it's verified that the extra reports are removed and that the switches send a separate report for manual control and separate report for z-wave control (which we understand is the reason why ZEN26 isn't supported), we'll implement it in the next production run and will share the firmware file with anyone that would like to update as usual.

If you don't have a Z-Wave USB stick to update, just get in touch with us so we can offer an alternative solution.


@agnes.zooz thank you very much for the quick update
Looking forward to hearing back from you in the near future


I know we're kind of late to this topic but just to clarify a little about the switches and their components and the issue with ZEN27 dimmers not fully turning off selected bulbs.

Components used:
ZEN22 VER. 2.0: TRIAC (thyristor)
ZEN27: MOSFET (semiconductor)

I checked the number of reported cases for bulbs not turning off with the ZEN27 and found 2 which is less than 1% of sold units so far but we will be watching this closely. We tested the dimmer with LED's from major brands rated for as low as 6W and haven't been able to replicate the issue. Most dimmers will have some leftover current even when off and that's why you'll see air gap switches included on most (so when you change the bulb you don't shock yourself).

Now the amount of voltage left in the ZEN27 may be higher than with ZEN22 and this has to do with the different type of 3-way communication we implemented for the ZEN26/ZEN27 switches. I'm not sure if it's strictly dependent on the MOSFET component or if it's something else but my understanding is that there's not much room for change if we want to keep the current 3-way/4-way solution.

As for load compatibility for switches that require a neutral (mentioned by @mike.maxwell), in a perfect world we'd have all dimmers working with all bulbs but the reality is that most dimmable LED's will come with a list of compatible dimmers instead, suggesting incompatibility with others. That's primarily due to the fact that there are 2 types of drivers used for dimming LED's - leading edge (good for TRIACs and MOSFET) and trailing edge (TRIAC will flicker, good for MOSFET). So you'll have bulbs flickering with GE, Leviton, and our ZEN22 dimmers that will not flicker with ZEN27 or other dimmers based on MOSFET (you'll be able to identify them by lower electrical ratings). None of the components are perfect because LED technology isn't standardized and we're seeing the same model of the same bulb work with one dimmer and then 6 months later, you buy this bulb again and it flickers with the same dimmer.

When developing the ZEN27 model we wanted to address the minimum load requirements that affected the ZEN22 dimmers (because of TRIAC) and the flickering issues we were seeing increasingly as a wave of cheap no-brand LED's flooded the market. That was on top of the simpler 3-way/4-way wiring.

Hope that clears some of the things up but if any of you have any specific questions or requests, we'll be checking in here on a regular basis :slight_smile: