Setting MPPTs work priority with CerboGX - Configurable?

Been wrestling with something similar on my own setup and thought it worth throwing open for discussion.

Running three Victron SmartSolar MPPTs here in Sussex — different roof aspects, so each string behaves quite differently across the day. East-facing array wakes up first, south carries the midday load, west picks up the evening shoulder. They're all feeding into a 48V lithium bank (Fogstar cells) alongside a Multiplus-II 5000.

The question that's been nagging me: within the Cerbo GX, is there any meaningful way to prioritise which MPPT gets to push harder when the batteries are approaching absorption? Or are they essentially just all racing to hit the same voltage setpoint and stepping back simultaneously?

In lead acid terms I imagine it matters less — the chemistry is forgiving — but with tighter lithium charge windows it feels like there could be some real gains (or at least some unnecessary losses) depending on how the MPPTs negotiate with each other.

I've had a poke around in VRM and the DVCC settings, and there's clearly something happening with the shared current control when DVCC is enabled. But I can't find a clean way to say "prioritise MPPT 1, then 2, then 3" in a sequential or weighted fashion.

Has anyone actually mapped this behaviour out properly? Keen to know:

• Whether DVCC's SCC current limit distributes load evenly or by some other logic
• If anyone's used Node-RED on the Cerbo to build custom priority rules
• Whether this even matters in practice or if I'm overcomplicating things

Real-world experience from mixed-string setups would be especially useful here.

@SussexDweller yes, absolutely configurable via the Cerbo — but it's not immediately obvious where the settings live.

In VRM or local Venus OS, head to Settings > ESS if you're running ESS, or dig into each MPPT's individual device page via the Cerbo. The MPPTs themselves don't have a strict "priority" hierarchy the way a multi-charger AC setup does — they all push simultaneously into the bus.

What you can control is absorption/float voltage sequencing by setting slightly different charge curves per MPPT, effectively making one "lead" while others follow. Victron's DVCC (Distributed Voltage and Current Control) is your friend here — enable it and the Cerbo coordinates the whole lot properly, preventing them fighting each other.

With three different roof aspects you'll get naturally staggered peaks anyway, which actually works in your favour rather than against you.

@SussexDweller three MPPTs on different roof aspects is exactly the kind of setup where the Cerbo earns its keep — mine on the boat has two SmartSolars chatting away happily via VE.Direct, and the shepherd's hut gets a third pointed south like a sunflower on a mission.

Worth noting: the charge current limits are where most people trip up — you're not really setting priority per se, you're throttling individual MPPTs so the Cerbo's DVCC layer can orchestrate the lot sensibly.

Set your DVCC SVS (Shared Voltage Sense) on, and let the BMS or the Cerbo be the boss — don't let each MPPT freelance or you'll get them arguing like siblings over the last biscuit.

Just to add a practical note to what @ExSquaddie49 and @LochLover have mentioned — with different roof aspects you'll likely find your MPPTs are rarely all peaking simultaneously anyway, which actually works in your favour. The Cerbo coordinates them through VE.Can or VE.Direct depending on how they're connected, and you can monitor each one individually in the Remote Console.

Worth checking whether you've enabled DVCC (Distributed Voltage and Current Control) as that's where a lot of the clever coordination happens — it lets the Cerbo manage charge current limits across all three units together rather than each one doing its own thing independently.

What are the rated outputs on each MPPT, @SussexDweller? That might affect which approach suits you best.

Really interested in this thread as I'm trying to figure out something similar for my narrowboat setup. Space on the roof is obviously limited so I'm running two MPPTs rather than three, but the aspect question is very real — panels at the bow vs stern can behave quite differently depending on which way you're moored.

Quick question for @ExSquaddie49 — when you say the settings "aren't immediately obvious," are we talking buried in the VRM portal, or is it accessible directly through the Cerbo's touchscreen menu? I've found some things only appear via VRM and it's not always clear why.

Also wondering whether the priority logic changes dynamically as conditions shift throughout the day, or whether you're essentially locking in a fixed hierarchy? That would make a significant difference for a boat that gets moved and re-moored regularly.