I think I lost "Cell Voltages"

[haraldhh]

How can I check if my BMS reports cell voltages and then on to VRM? I have them in the GUI v2, and I did have them in VRM with the older serialbattery using USB. Now I got my CAN-hat working and I do still see cell voltages in the GUI but they aren't available in VRM anymore.

Using the Custom Widget in VRM I can list stuff that the Venus OS reports from the BMS but Cell Voltages isn't there anymore.

I have to make a test where I reconnecft the BMS via USB and check if Cell Voltages are available in VRM again.

edit: using the remote console in VRM I'm unable to see Cell Voltages in the GUI. Maybe VRM isn't just up to it?

Nightly from a few days back

[haraldhh]

Some other Harald asked kind of the same thing. VRM doesn't know about Cell Voltages, only highest and lowest cell voltage. Wonder why I had a custom widget then, oh well.

Link to previous discussion; Louisvdw/dbus-serialbattery#261

[mr-manuel]

You can check with these steps:

1. Check with dbus-spy over SSH, if you see all cell voltages
2. Check the local Remote Console/GUIv2 over the browser
3. Check if Remote Console/GUIv2 over the VRM Portal

I'm not aware of any possibility to display the single cell data on the VRM Portal itself, except for the Remote Console, which loads the data directly from the GX device.

If you need support, open a support issue.

[haraldhh]

Yes, Cell Voltages are available in dbus-spy and in GUI-v2 in the same LAN.

I have never seen Cell Voltages in the Remote Console, only in LAN. I suspect the Remote Console in VRM is a different version, or does it really download the data (presentation layer software?) from my GX device?

edit: MOSFET temperature is also missing in the Remote Console via VRM

edit²: I had a discussion on Victron's board. Cell Voltages are newer going to show up in VRM, this is probably why the Remote Console in VRM doesn't show them as well. I guess the presentation layer in Remote Console is the stock variant downloaded from Victron's site, and them the communication between that and the GX device is MQTT, json or something and it doesn't help if that data does contain the values if the presentation layer doesn't know about it.

edit³: GUI-v1 in Remote Console does show Cell Voltages!

[mr-manuel]

The VRM portal checks the checksum of the local WASM build (the existing sha file). If it's different, then the WASM build is downloaded from the GX device (Remote Support has to be enabled to be able to deliver the file). Currently it checks /var/www/venus/gui-beta. Check if /var/www/venus/gui-v2 is a folder or a symbolic link. In your case could be, that this is a folder. Updating to the latest Venus OS should solve the problem.

[mr-manuel]

Also a reboot/restart of vrmlogger service is needed, to tell the VRM portal, that there is a new/different GUIv2.

[haraldhh]

/var/www/venus/gui-v2 is a symlink to /var/www/venus/gui-beta on my v3.53 system.

I have never had Remote Support enabled. The VRM now shows me a version of the Remote Console that has both Cell Voltages and MOSFET Temperature shown to me in GUIv2. After I have updated to v3.53 and dbus-serialbattery v2.0.20250107dev.

[haraldhh]

I stumbled upon this page; https://communityarchive.victronenergy.com/questions/245056/venus-os-modifying-gui-v2.html

Apparently it's possible for serialbattery to modify the WebAssembly to show Cell Voltages on LAN. But why doesn't the version running Remote Console in VRM show Cell Voltages? This might be a Victron problem, I suspect there's some cacheing going on here.

[haraldhh]

After upgrading to v3.53 and dbus-serialbattery v2.0.20250107dev something must have triggered the kill cache mechanism in VRM and I now can see Cell Voltages and MOSFET Temperature in Remote Console in VRM.

I do not have Remote Support enabled. Never have had.

[haraldhh]

Oh, according to a Victron guy I can't be using CAN since CAN cannot convey Cell Voltages? Maybe there are other protocols that run on CAN, I don't know.

[mr-manuel]

That is wrong. Only the Victron stock CAN driver cannot do that. With dbus-serialbattery it works. V2 has many inprovements regarding that. Check the docs and select the dev version on top right to change the docs version

[haraldhh]

Yes, it's quite obvious to me that it's wrong since I have it running. I think the Victron guy was talking about their own protocol on CAN. It works nicely, thanks!

[haraldhh]

I wonder what's going to happen with the Victron stock CAN driver when they are now starting to monitor cells too?