Using Multiplus II 48/5000/70-50 GX and a cerbo togehter

Been running a Multiplus II 48/5000 paired with a Cerbo GX in my static caravan setup for about eight months now, so thought I'd share a few observations since this combination seems to be cropping up more frequently.

The integration is genuinely solid once you get your head around the VE.Bus configuration. That said, I'd push back slightly on the assumption that the Cerbo is essential from day one — if you're a student project or working to a tight budget, the CCGX does a similar job for less. Worth considering.

A few things that caught me out initially:

• ESS vs off-grid assistant — make sure you're clear which mode you actually need. Off-grid installs should generally use the off-grid assistant rather than ESS, despite what some guides suggest
• Grid code settings — even in a fully off-grid context the unit ships with country-specific grid codes active. You'll want to disable or adjust these appropriately
• DVCC — the Cerbo handles this well with compatible BMS units, but if you're using Fogstar or similar cells with a third-party BMS, double-check compatibility before assuming it'll just work

The VRM portal is genuinely useful for remote monitoring once everything's communicating properly, though I've found the data logging interval settings a bit buried in the menus.

Curious whether anyone else here has pushed the 5000VA unit harder during winter — I'm finding my solar harvest drops considerably and wondering how others are managing the AC coupling side when generation is limited.

What MPPT are you pairing with yours?

@DucatoProject great setup to document — the Multiplus II GX variant actually has the Cerbo functionality built in (the "GX" suffix on your unit), so technically you're running duplicated GX hardware there. Worth checking in VRM whether both are showing as separate devices, as this can occasionally cause conflicts on the VE.Can bus.

In my Vivaro-based system I run a standard Multiplus II 48/3000 without the GX suffix, paired with a dedicated Cerbo GX — that's the cleaner architecture if you're adding a touchscreen display later via the GX Touch 50.

One practical thing: make sure your Cerbo is set as the primary VE.Can device in the settings, otherwise DVCC (Distributed Voltage and Current Control) can behave oddly, particularly if you're running a Victron SmartShunt alongside it.

@VivaroWanderer is right — the Multiplus II GX variant has the VenusOS brains baked in, so running a separate Cerbo alongside it is technically redundant (you're paying twice for the same party trick).

That said, there are legitimate reasons to keep the Cerbo: dedicated HDMI display output, more physical ports, and the touchscreen compatibility for a GX Touch 50/70 — the integrated GX unit won't drive those externally.

Worth checking in VictronConnect which device is actually acting as the DVCC master, because having two Venus devices on the same VE.Can network arguing over who's in charge is about as productive as two skippers on one boat. 🚢

Disable the internal GX via Remote Console → Settings → General and let the Cerbo do the heavy lifting if that's your preferred setup.

Worth adding — if you've already got both units running together it's not wrong as such, just a bit redundant on the hardware side. Some folks actually prefer keeping a separate Cerbo because it means if one unit needs swapping out or goes faulty, your monitoring stays up independently. Had a similar situation with my cabin setup and keeping things modular saved me a headache when I had to RMA a unit. Just something to weigh up before you start pulling kit apart.

Good points from everyone above. One thing worth adding to what @DeclanKnight57 was getting at — if you're keeping both units running together, do make sure you've only got one acting as the VRM portal connection, otherwise you can end up with confusing duplicate entries on your VRM dashboard. Took me a while to sort that out on a similar setup. Also worth checking your DVCC settings are consistent across the system — having two Venus devices in the mix can occasionally throw up odd behaviour there. The Cerbo isn't wasted though; the extra GX Touch display support and the physical relay outputs can still be genuinely useful depending on your setup. What battery chemistry are you running @DucatoProject? That might affect whether the redundancy actually gives you anything practical.