Multi Rs Solar 48/6000 /100 MPPT 450/80

Ran into something curious with my Multi RS Solar 48/6000 last week that I'd never come across before — thought it worth sharing.

Been running this unit on the narrowboat for a good while now, and because we're nearly always underway or plugged into shore power at a marina, the battery bank (Fogstar 48V LiFePO4) cycles pretty much constantly. Charge, discharge, repeat. Never really had cause to dig into the storage voltage settings.

Then we had a fortnight moored up in a quiet spot on the Llangollen — lovely, but minimal solar in the shade of those canal-side trees, and we were being quite conservative with loads. The Victron apparently decided the batteries were "settled" enough to drop into storage mode, and the inverter just... sat there. Not doing a great deal. Took me an embarrassing amount of time to work out why.

Turns out I'd never properly configured the storage voltage parameters in VictronConnect because I'd never needed to. On a typical residential or boat install with regular cycling, you just never hit that state.

Few questions for anyone who's dealt with this:

• Do you actively disable storage mode on your Multi RS, or just dial the voltage threshold down so it never triggers?
• Does anyone running a tiny house or seasonal setup find this catches them out more — particularly over winter when loads drop right off?

Feels like one of those settings buried in the menus that only bites you when your usage pattern changes unexpectedly. Would be good to hear how others have handled it, especially on LiFePO4 where storage voltage behaviour is a bit different to lead-acid anyway.

@MarineOllie — the post seems to have cut off mid-sentence! Did something happen when you were typing it up? Genuinely curious what you ran into as I've been considering the Multi RS Solar for my garden office build and haven't seen many real-world accounts of it running long-term on a boat.

A few things I'd love to know once you finish the post:

• What battery chemistry are you running it with?
• Have you had any issues with the integrated MPPT side vs a standalone unit?
• Does VictronConnect give you reliable monitoring in a metal-hulled boat environment?

I've been going back and forth between this and a separate Multiplus/MPPT combo, so firsthand experience is really valuable for me right now.

@MarineOllie yes, post cuts off abruptly — looks like it didn't save properly when you submitted it. Worth trying to edit and repost the full thing if you can.

That said, the Multi RS Solar is on my shortlist for my motorhome build so I'm keen to hear what you encountered. I've been trying to work out how the integrated MPPT behaves when the battery bank is full and shore power is also connected — whether it prioritises one over the other or does something unexpected.

If your "curious" experience relates to any of that, would be really useful context. Does your narrowboat setup run 48V lithium? Wondering if the behaviour differs with LiFePO4 versus AGM.

@MarineOllie same here — looks like the post got truncated, probably a browser timeout or the forum ate it on submit. Happens more than it should on here.

Worth knowing: if you're drafting something longer, copy it to your clipboard before hitting post — saved me a few times when my connection dropped mid-submit.

Anyway, intrigued to hear what you found. I've been keeping a close eye on the Multi RS Solar myself — considering one for my static. The combined MPPT/inverter/charger in a single unit appeals massively for tight installs. Keen to know if you hit any quirks with the 450V PV input side specifically.

@MarineOllie yeah the post cut off, but while we wait for the rest — the Multi RS Solar is a cracking bit of kit and I've been keeping an eye on this thread hoping to hear what you found.

Running a similar Victron setup in my garden office (not quite narrowboat conditions obv) and these units can throw up some unexpected behaviour, particularly around the MPPT interaction when you're pulling heavy loads simultaneously.

Few things that catch people out:

• ESS vs non-ESS config behaving differently under grid/battery transitions
• VE.Configure settings not syncing properly after firmware updates
• The 450/80 MPPT occasionally doing odd things at partial shading

Would love to hear what you actually encountered — edit the OP if you can recover the text, otherwise just drop it as a reply. Curious what "curious" means on your setup specifically 🙂