question

oceanwolfe avatar image
oceanwolfe asked

Can I access my Multiplus for programming via the Cerbo GX?

I'm trying to finalize the layout of my energy system components on my sailboat. After the install is finished, I'd like to NOT have to connect anything to the Multiplus for updating software or programming. It seems like I should be able to connect the laptop to the Cerbo GX using the MkIII USB cable .I will locate the Cerbo for more convenient access when I need to do Multiplus programming, but can't figure out how to achieve this. It doesn't seem to work when the Multiplus is connected to GX via VE Bus using the ethernet cable called for by the Cerbo instructions. Is there a different cable that I an use to achieve this higher-level programming connection?

cerbo gxmultiplus ve.buscommunication protocol
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

6 Answers
Kevin Windrem avatar image
Kevin Windrem answered ·

The VE.Bus only allows a GX device (Cerbo in this case) OR the MK-3 USB cable to be connected at the same time. Connecting the MK-3 to the bus will cause Cerbo to not see the Multi. Victron recommends disconnecting the GX device from the VE.Bus prior to connecting the MK-3.

I use an ethernet female-female joiner at the back of my CCGX to connect the MK-3 rather than looping through the CCGX. Not as convenient but it seems to work.

If I recall correctly, if you leave the MK3 connected but shut down the app or disconnect the USB side of the MK3 from your computer the GX device will eventually reconnect to the Multi and function normally but I'd test this carefully in your system to make sure.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

If the GX is internet connected, use Remote VE.Configure.

2 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

peter-edwards avatar image peter-edwards commented ·
Thanks Guy, using the remote VE.Configure, can you do the initial 3 phase setup on three Multi 2's?
0 Likes 0 ·
Guy Stewart (Victron Community Manager) avatar image Guy Stewart (Victron Community Manager) ♦♦ peter-edwards commented ·
No, the 3 phase programming requires a local connection


I would recommend using VictronConnect for this now, it’s much better for that stage.

I’ll have an updated training soon.

0 Likes 0 ·
oceanwolfe avatar image
oceanwolfe answered ·

Thanks Kevin, that was very helpful, if not the desired answer. I had thought that the either Mk-3 or GX only choice was when attaching to the Multiplus. In other words, didn't realize it was a network limitation rather than a device limitation. Guess I hav to get an extension for the Mk-3 so I can access it without having to pull panels from a hard to get to Multiplus.
This sure seems amazingly klunky it the many network limitations. Seems like a growing patchwork rather than a planned network system.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

oceanwolfe avatar image
oceanwolfe answered ·

Guy, so often the official responses seem to require internet access. That may be fine at the dock, but I'm setting up for extending cruising and anchoring out, so I need a system that I can operate that does NOT require internet access. Having a hard time getting there.
At this point feeling very foolish for buying the Cerbo GX because I thought it would serve to resolve this issue. Obviously not the case.

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Guy Stewart (Victron Community Manager) avatar image Guy Stewart (Victron Community Manager) ♦♦ commented ·

I understand, in your case it sounds like the MK3 is the solution, with some wiring arrangement (such as an accessible joiner) to allow access.

But what kind of ongoing re-programming and updates do you foresee yourself needing once the system is commissioned?

The most common on a boat is monitoring, turning the Multi on or off, or adjusting the AC input current limits - these CAN be done with the Cerbo without an MK3 or internet.

The Victron system is absolutely designed and intended to operate without requiring an internet connection - though having one GREATLY increases the features and potential of the system.

I would like to hear what the constraints are (the common things you expected to be able to change on the Cerbo GX that you cannot)?

Somewhat unofficially, there is a general prioritising principle at Victron that if something is possible to do one way, we won't be focused on doing it all the possible ways, even though it might be nice. There are exceptions of course, and if there are specific and obvious changes that you (and others like you) need to be making, then it is all possible to make it happen.

It can sort-of work to leave the CerboGX connected at the same time as the MK3, and even using the VE.Bus as passthru on the Cerbo. The MK3 will take over the control, and the Multi will become invisible/'OFF' to the CerboGX while it is connected, BUT in some cases it did cause issues, so to eliminate the potential of finding a strange edge case the advice is to have it disconnected, and only one at a time.


I am certain that you will not regret getting the Cerbo GX in the long run, it has some limitations as you are finding, but it is a superb unit that already has an incredible feature set, which is constantly improving.

0 Likes 0 ·
oceanwolfe avatar image
oceanwolfe answered ·

Sorry Kevin, what you said finally fully sunk in. The female-to-female link is to connect the ethernet cable plugged into the Cerbo to the Mk-3 cable, right? Seems strange it won't pass that to the other VE Bus port on the Cerbo, but that's life.
Many thanks.

2 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Kevin Windrem avatar image Kevin Windrem commented ·

Yes, the female-female ethernet is to extend the ethernet cable when it's disconnected from Cerbo.

It's been a while but I do think it works if you connect the MK3 to the Cerbo VE.bus loopthru. That is, I think the MK3 takes over the bus and the Cerbo stops seeing the Multi.

What I can't remember is if Cerbo regains control after you unplug the USB side of the MK3. Worth a test.

I believe Victron recommends disconnecting the Cerbo when using the MK3 and visa-versa.

0 Likes 0 ·
bathnm avatar image bathnm Kevin Windrem commented ·

I can confirm it does. I have frequently had the Cerbo and MK3 on the bus, and as soon as the MK3 is no longer connected to VE.Condig the Cerbo will start doing its stuff again.

0 Likes 0 ·
projectwaterlily avatar image
projectwaterlily answered ·

Sort of related to this, hope you dont mind me hopping on. I have a new Muliplus-2 and have a Cerbo GX on my boat. Am i correct in thinking just connecting the ethernet cable between these will allow me to program the Multiplus-2 as required, without the need for the Victron Energy Interface MK3-USB (VE.Bus to USB) – ASS030140000?

4 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Kevin Windrem avatar image Kevin Windrem commented ·
You can though VRM using remote configure.

For local updates you need the MK3-USB and VictronConnect (Mac/Windows) or veconfig (Windows only). You need veconfig for assistants.

0 Likes 0 ·
projectwaterlily avatar image projectwaterlily Kevin Windrem commented ·
thanks Kevin. Can you expand on what 'local updates' means - is this firmware updates? so GX wont do this? thanks!!!
0 Likes 0 ·
Show more comments

Related Resources

Additional resources still need to be added for this topic

Cerbo GX product page

GX family product range

Cerbo GX & GX Touch datasheet

Cerbo GX Manual

Venus root access document