Branchement victron

Been staring at my Victron wiring diagram for the past hour and my brain's gone to mush — hoping someone here can help me make sense of it.

I've got a Victron SmartSolar MPPT 100/30 arriving next week for my static caravan conversion, and I've been trying to plan the wiring layout before it turns up. I've got a rough sketch of where everything needs to go, but I'm second-guessing myself on a few of the connections — specifically around:

• Where the battery temperature sensor ties in
• Whether the BMS load output goes direct to the MPPT or via the main bus bar
• The correct order of fusing between panels → MPPT → battery

I'm running 2x 200W Renogy panels in series and a Fogstar Drift 200Ah LiFePO4 battery. Pretty standard setup I'd imagine, but I don't want to fry anything expensive on the first power-up.

Has anyone got a wiring diagram they've used for a similar Victron MPPT + LiFePO4 setup that they'd be willing to share? Even a rough hand-drawn one would be useful — just something to cross-reference against what I think I'm doing.

Also — is the Victron app wiring diagram tool actually reliable for generating accurate connection guides, or does it miss things?

Anyone who's done this in a static or van conversion, would love to hear how you approached it.

Reply by DebbiePowell76:

Ha, @RussScott, we've all been there staring at those diagrams until the lines start swimming! 😄

First thing — what battery setup are you working with? Lithium or AGM/gel? Makes a difference to how you configure the MPPT settings once it's wired in.

The 100/30 is a cracking little unit for a motorhome. Basic wiring order to remember: always connect batteries first, then solar panels last — never the other way round or you risk damaging the controller.

Also, have you got the Victron Connect app downloaded? Honestly makes setup so much easier than fumbling with DIP switches. Bluetooth built into the SmartSolar so it pairs straight away.

Tell us more about your setup — panel wattage, battery bank size — and we can give you much more specific advice! 👍

Reply by CotswoldVanLifer:

@RussScott the 100/30 is a cracking bit of kit, you'll be chuffed once it's all wired up! The title's in French but don't let that throw you — the wiring principles are identical regardless.

Main thing people trip up on: always connect your battery to the MPPT before connecting the solar panels. Victron are pretty firm on that in their documentation. Also make sure you've got an appropriately rated fuse on the battery cable, as close to the battery terminal as practical.

Are you running it alongside a battery-to-battery charger or just solar? And what battery chemistry — lithium or AGM? Makes a difference for how you configure it in the VictronConnect app. Happy to walk you through the Bluetooth setup once you've got it mounted — it's actually quite straightforward once you've done it once! 🙂

@RussScott what panels are you running and what's your battery bank? That'll change where the conversation goes.

With my narrowboat setup I made the same mistake initially — wired the MPPT before fully understanding the load terminals. On the 100/30 your connections run: panels into the PV input, then a separate pair for battery, and the load output is optional (handy for small 12v circuits but not essential if you're running everything through a distribution board).

The golden rule Victron always stress: connect battery first, panels last — and disconnect in reverse. Gets you every time if you're used to other kit.

Once it's live, the VictronConnect app via Bluetooth makes the whole thing much less intimidating — you can actually see what's happening in real time rather than guessing from indicator lights.

@RussScott post the actual diagram you're confused about — "wiring diagram" covers everything from a back-of-fag-packet sketch to a full Victron VE.Smart network schematic, and we're all just guessing otherwise.

That said, the golden rule with the 100/30: PV to MPPT first, battery second when connecting, reverse when disconnecting — get that wrong and you'll learn an expensive lesson about why Victron's warranty doesn't cover self-inflicted stupidity.

Also @ForestJenny is right, panel Voc matters — the "100" in 100/30 is your absolute maximum PV input voltage, not a suggestion. Seen lads wire two 24V panels in series in winter and wonder why their MPPT smells funny.

@RussScott I went through exactly this with my garden office setup using a 75/15 — the Victron wiring looks more complicated than it actually is once you break it into sections.

The bit that caught me out was the order of connections. Are you confused about the battery first, then panels rule? Or is it more about where the fuses/breakers need to go in the circuit? There's a significant difference between getting the sequence wrong and getting the actual wiring topology wrong.

Also — are you planning to use the VictronConnect app to configure it afterwards? Worth making sure you've got Bluetooth sorted before everything's buried in a cupboard.