DIY - Welche MPPT und Konnektivität MP2, VM-3P75CT, Batterie?

Been thinking about this a lot lately as I'm planning a similar-ish setup for my van conversion, possibly scaled up for a static tiny house install down the line.

Looking at a Multiplus-II 3000/48V paired with around 5kWh of lithium (probably Fogstar Drift 48V or a DIY 16S280Ah setup). Solar-wise I'm eyeing roughly 2kWp of panels, but I'm genuinely confused about which MPPT to pair with it.

A few questions I can't quite nail down:

• Does the SmartSolar MPPT 150/45 make sense here, or is that overkill/underkill for 2kWp into a 48V bank?
• If anyone's using the VM-3P75CT energy meter — how are you wiring that into a single-phase UK setup? Seems designed with three-phase in mind and I'm not sure how it translates
• What's the minimum cable spec between the MPPT and the Multiplus-II DC busbar for a setup this size? I keep getting different answers

My neighbour's an electrician but he's more domestic DNO stuff — he's happy to help with the G98/G99 notification side once I'm clearer on the actual component choices, but the Victron ecosystem specifics are a bit beyond both of us right now.

Anyone running a comparable Victron setup with a VRM-monitored system in the UK? Particularly interested in how you've handled the meter placement relative to your consumer unit.

@DownsDweller the MP2 48V paired with a decent MPPT like the Victron SmartSolar 150/35 works a treat — done exactly this in my van build.

Key thing people miss: get the VM-3P75CT energy meter sorted before you commission everything, saves a massive headache later.

For batteries, Fogstar Drift 48V is cracking value if you're on a budget, or splash out on proper Victron Lithium if you want the full seamless integration.

One heads-up — if you're scaling to a static install later, wire it properly from the start. I bodged my van setup thinking "I'll sort it later" and... well. 😅

The VRM portal via Cerbo GX ties everything together nicely for monitoring both scenarios too.

@George1975 good shout on the SmartSolar — worth noting if you're planning to scale up later, the 150/100 might be worth the extra outlay now rather than swapping controllers down the line.

@DownsDweller one thing I'd flag from my cabin setup: make sure your VM-3P75CT wiring is sorted before you commission the MP2. I made the mistake of trying to configure it all live and it was a right faff.

Also, what battery chemistry are you going with? Fogstar Drift LiFePO4 seems popular here for 48V builds and plays nicely with Victron's ecosystem via their BMS integration. Worth checking compatibility early rather than retrofitting later.

@PartnerProject @George1975 solid advice already here, but worth flagging — the thread title's in German 😅 either OP's got a very international browser or they're planning to install this thing in Bavaria.

On topic though — if you're going static tiny house and van, seriously consider the VM-3P75CT energy meter

@CotswoldNomad ha, maybe @DownsDweller's van is already halfway across the Rhine! 🚐

One thing nobody's mentioned yet — if you're going the VM-3P75CT route (Energy Meter for grid monitoring), make sure your installation point has decent CT clamp access on the incoming phases. Sounds obvious but I bodged mine initially because the meter cabinet was a nightmare to retrofit into. Also worth pairing that with VRM portal monitoring from day one — the historical data is genuinely invaluable when you're troubleshooting why your batteries aren't hitting full SOC on that one cloudy Tuesday in November.

For the battery side on 48V, I'd strongly recommend looking at Fogstar Drift cells if you're going DIY, or pre-built Pylontech US5000 if you want plug-and-play DVCC integration with the MP2. The Pylontech/Victron comms stack just works.

@TracyAllen curious what you were about to say there — post got cut off!

On the VM-3P75CT (assuming that's the Carlo Gavazzi ET340 energy meter for grid-parallel setup) — worth double-checking your DNO will accept the configuration before you commit. Some UK suppliers are still funny about export limiting on static installs even with the proper G98/G99 notification.

For the MPPT question specifically: if you're pairing with a 48V MultiPlus-II 3000, the SmartSolar 150/85 is the sweet spot unless your array's genuinely large, then step to the 150/100. Keep everything talking via VE.Can rather than VE.Direct if you're running multiple controllers — makes the Cerbo GX integration far cleaner in my experience on the static caravan side of things.