Victron connect with Multiplus

Been down this rabbit hole myself when I switched the cabin over to LiFePO4 last year.

Short answer: no, you can't configure a Multiplus through VictronConnect alone. The app is great for monitoring and tweaking simpler kit like the MPPT controllers, but the Multiplus needs VE.Configure (Windows software) to change the bulk/absorption/float thresholds properly. Pain in the backside if you're not near a laptop.

What you actually need:

• MK3-USB interface (the dongle you're thinking of, ~£50ish)
• A Windows machine running VE.Configure 3
• Or alternatively, a Cerbo GX / GX Touch setup if you want remote config capability

I'm running a Multiplus-II 24/3000 and getting the charge profile dialled in for my Fogstar Drift cells took a bit of faffing. Key thing with LiFePO4 is killing the float or setting it very low — the Multiplus defaults are way too aggressive for lithium.

If you're on a boat (sounds like you might be from the "on board" comment), also worth checking your BMS has a proper charge disconnect signal wired to the Multiplus assistant — otherwise you're relying on the BMS to hard-cut under load which isn't ideal.

Anyone else found a decent workaround for configuring these without dragging a Windows laptop out? Tempted to just keep an old Lenovo beater dedicated to VE.Configure at the cabin but feels daft.

@GrumpyBuilder is right on the core point, but worth clarifying why for anyone landing on this thread later.

The Multiplus's assistant framework (things like ESS, generator start/stop logic, ignore AC input) simply isn't exposed in VictronConnect — you need VEConfigure via a MK3-USB interface, or a GX device (Cerbo, CCGX etc.) running VEConfig remotely.

From my own static caravan setup: I run a Cerbo GX which lets me tweak charge curves and inverter settings remotely through VRM without dragging a laptop out. Absolute game-changer once you've got LiFePO4 — getting those absorption/float voltages dialled in properly matters enormously with Fogstar or any other lithium pack.

Don't try guessing settings through VictronConnect alone — you'll miss critical charge algorithm parameters that protect your cells long-term.

Good shout from both of you on the fundamentals. Worth adding the practical workflow for anyone actually doing this:

You'll need VEConfigure (Windows only, or via Wine on Linux) connected via the MK3-USB interface for proper Multiplus configuration. VictronConnect handles monitoring and basic stuff via Bluetooth, but the assistant tab in VEConfigure is where you set charge algorithms, transfer switch behaviour, and LiFePO4-specific absorption/float voltages.

If you're running a Cerbo GX, you can push some settings remotely via VRM, but it's still not the full parameter set.

For LiFePO4 specifically, make sure you're coordinating the Multiplus charge settings with whatever BMS you're running — I've seen setups where the BMS CVL/CCL signals via DVCC were being overridden because VEConfigure values weren't set correctly first.

So just to make sure I've got this straight in my head — if I want to configure my Multiplus for the narrowboat setup (currently running Fogstar 12V LiFePO4s with a basic BMS), I absolutely need VEConfigure or VEFlash rather than just the VictronConnect app?

Asking because I've been merrily poking around in VictronConnect thinking I was doing something useful, when apparently I've just been admiring the graphs like a complete muppet 🙈

@Bazza60 does that workflow require the MK3-USB interface specifically, or can you get away with anything else? I've seen some suspiciously cheap "compatible" cables on Amazon and I'm wondering if they're the kind of false economy that ends up frying something important on a narrowboat 20 miles from the nearest chandlery...

One thing nobody's mentioned yet — if you're doing this for a backup/emergency setup like me, VEConfigure has a "shore power assist" mode worth looking at once you've got the config side sorted via MK3 cable.

Also @SunnyFisher for the narrowboat specifically, check your charge current settings carefully. Canal setups often have dodgy 16A shore hookups and the Multiplus can trip the bollard supply if it's set too aggressively. Caught me out before I dialled mine back.

Fogstar Drift cells btw — dead easy to integrate once VEConfigure is sorted, the absorption/float voltages are well documented.

@SunnyFisher yes, MK3-USB interface + VEConfigure on a Windows laptop — that's your narrowboat toolkit sorted, no getting around it.

Worth noting: if you're tight on space or doing it remotely, a Raspberry Pi running Venus OS (essentially a DIY Cerbo GX) gives you a permanent VRM portal connection so you can tweak charge voltages without lugging a laptop down the companionway every time your Fogstar cells drift slightly. Saved me no end of grief on the static van install. Just don't cheap out on the MK3 cable — the clones are genuinely hit-and-miss and you'll spend more time debugging comms issues than actually configuring anything.