Clock Class for Devolo Thermostat (MT02650)

Hello everyone,

I have several ZWave Develo Thermostats MT02650 which have the Danfoss living connect Thermostat as hardware basis with a Devolo Firmware.

I switched from FHEM to OpenHab. Now I am missing the clock command class in OpenHab. CCS is also missing, but it is not necessary as it is strange to handle anyway.

I know from my own experience and from the Danfoss support hotline, that you need the clock set correctly on those devices, as the device will perform an automatic calibration procedure after initialization. During this calibration, the device will step by step open its valve in the morning hours and measure how the room is heating up (depending on room and heater size). This can happen for up to a week until the process is finished. You can read about this in the official Danfoss documentation (chapter 1.8):

In FHEM I added a “rule” to automatically update the clock once a day since it was drifting quite heavily on some devices.

If you cannot set the clock, the devices will perform this calibration heating randomly during the day. In my case I have one device which is doing it in the evening at the moment when the child needs to sleep. So I have to remove the battery, to abort this procedure.

**I would like to add the clock command class, to be able to manually set and read the clock. **
How can we do this? Or is Openhab doing this somehow?

This may be connected to an old thread which I found:

Maybe the clock was removed some time ago?

I see that the clock class is not existing anymore in the ZWave database:

But I can also see that it should be there from the documentation:

What could be the next steps?
What can I do to help?
Can I add the class myself?

Currently this doesn’t seem to be in the database. The command class would need to be added, and the time_offset channel would need to be added to the command class.

Please see the following link for updating the database.

Hello Chris,

I already registered and can edit the database but I need a corrected XML file.

Is there anywhere a documentation about the structure and how to update and load the xml files into OpenHab so I can test before uploading?

I have seen the node xml files in the openhab2-userdata/zwave directory.

Are we talking about those files? How can I load them into openhab after changing them?

Thx for a kick start on this topic.

You need to update the database first. Then the XML file can be created and we can update the binding.

No - this isn’t really supported in openHAB. All XML files need to be part of the binding so that the openhab core can read them on binding start.

No - that’s a completely different XML file. These XML files are the binding persistent storage so that it saves information about devices when the binding restarts.

The XML files provided by the database are read by OH to create the thing definitions.

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I added the clock class (basically copied the settings from the Danfoss version of the thermostat (LC-13)).

But I have further question:

  1. What is “NIF” and do I need it? In the Danfoss it is not selected, but in the Devolo it is selected on almost all classes.

  2. Clock Time Offset is marked as [deprecated]. Is this an issue?

  3. There is an information that “Endpoint 0 has no command class linked to the basic class”. Is this an issue?

Finally, it seems that I also edited the Danfoss Thermostat LC-13 by accident. How can I undo this change?

It indicates if the device marks this command class in its NIF (Node Information Frame). Ideally this should reflect the device configuration, but it’s not used by the binding so it does not matter.

No. I will remove this though, but it is just a name issue.

No. It’s not required and only used on some classes.

You can’t. If you’ve added something you want removed, just rename it to “REMOVE ME” or something like that and we should sort this when you click the request review button.




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How is the procedure for me to test this?

Wait for the changes to get merged, download the latest zwave snapshot, either upgrade manually or use this script:

How can I see when the changes are merged? I checked the GitHub ZWave Binding page, but I cannot see any new commit. Which GitHub project are we talking about? This one?

No - there is none at this point. Please be patient - I normally do an update once a week on the weekend.

Ok, thank you! :+1:

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Hello Chris,

I have seen, that you committed the clock class into the ZWave repository.

Now I am considering whether to update the ZWave binding manually or wait for an OpenHab release (maybe milestone release).

Do you know when the change will be integrated into OpenHab?
How much risk is there with manual updating the binding?

Thanks a lot!

This was done a long time ago. What device are you interested in? Is it this one (MT02650)?

Sorry, but I’m not exactly sure what change you refer to? Is it the changes to this device? If so, then that will already be in 2.5.3

I meant the Clock Time Offset added in Database update (#1313) earlier this month.

I was wondering when this will be part of an OpenHab release or if I update only the binding?

Ok, so to clarify though, you are referring to this device? The reason I ask is that you talked about the fact that I “committed the clock class into the ZWave repository”. This PR doesn’t do that - the clock class was commited a long time ago. This PR adds the time offset channel.

As I said, it is already in 2.5.3. This is the most recent release - there will not be another full release of OH2.5.

Sorry, yes I was referring to this device.

My goal is to have the clock of this device set correctly as mentioned above in this topic. That was the reason for the change. At the moment, the clock is set to a random time when you put in the batteries or when device is first turned on. The correct clock is necessary to have a correct initialization procedure which should take place in the morning. At the moment it happens at a random time.

I just installed 2.5.3 so I can check if it is better.

Can I directly see somewhere in OpenHab that the time offset is available for this device. Or even better, can I read the current clock of the device? As far as I can see there is no new item or setting.

Yes, that is what the clock offset channel does - it provides the offset of the PCs time to the device time.

No - this is of limited use in general - that’s why we provide the offset. Why do you want to know the time?

There is - that’s what we added. Have you deleted and re-added the device?

Ah, no, I haven’t. Good that I asked. I will do this tomorrow.

Thank you for the fast feedback. I will report asap. :slight_smile:

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Giving the promised feedback, the clock sync is there and I see values in it (time offset). As far as I could see during the colder days, the devices did not heat up during the night anymore (which was the initial problem), but it was only a short monitoring period. I will check again next winter.

What bugs me a bit is that the time offset has some very random numbers in it and they are changing when my Openhabian has restarted. Shouldn’t they stay the same for the same device?

For example the thermostat in my office room has a time offset of zero most of the time and sometimes shows very high values over a short time and sometimes very low values over a longer time.

Maybe you could add some words on how that time offset actually works for my better understanding? Thank you!