What is the Victron answer for 117 panels that would need 17 MPPT's?

Bit of a beast of a system this one! 🤯

Had a similar (though much smaller!) head-scratcher when I was speccing up the charging setup for my boat and garden office combo — once you start stacking panels you quickly realise the MPPT situation gets out of hand fast.

So here's the question for the Victron nerds among us: if you've got a large residential or commercial-ish setup running, say, 117 panels across mixed wattages (think a mix of 460W and 625W panels like the Astro Energy range), what's the proper Victron way to handle it without ending up with 17 separate MPPTs?

A few options I've been turning over:

• Victron SmartSolar 250/100 units in parallel — but that still stacks up cost-wise
• String inverter approach feeding into a Quattro setup?
• Some kind of AC-coupled arrangement with a third-party string inverter doing the heavy lifting?

The Deye route (as some are going with similar panel counts) seems to be popular for large residential, but I'm curious whether a full Victron ecosystem can compete on cost and practicality at that scale — especially if you want proper GivEnergy or Venus OS monitoring baked in.

Anyone on here actually run a Victron setup at this kind of scale in the UK? Planning permissions aside 😅, I'd love to know how you'd architect it.

What would you do with 117 panels and a Victron-only brief?

@JimWilson that's a serious array! With a system that size you're probably looking at the Victron Large System approach — combine panels into higher-voltage strings and use fewer, larger MPPTs rather than multiplying small units.

Victron's SmartSolar 450/100 handles up to 450V input which lets you string more panels in series per MPPT. Crunch your string voltages properly and you could potentially halve the number of charge controllers needed.

Worth running it through Victron's MPPT calculator — it'll show optimal string configs.

Also consider whether you actually need individual MPPT per string or whether mismatched orientations/tilts are even an issue. If all 117 panels face the same direction with no shading, fewer MPPTs on longer strings is cleaner.

What's the panel wattage and site layout like? That'll massively affect the answer.

Has anyone actually modelled this in VictorConnect or spoken to a Victron distributor directly? With 17 MPPTs you're deep into territory where the Cerbo GX becomes essential just to manage the comms load — all those units on VE.Can will need careful address assignment.

Also worth considering: at that scale, are all 117 panels identical spec and orientation? If there's any variation, grouping by string characteristics across the MPPTs becomes critical, otherwise you're leaving yield on the table.

For my static caravan setup I only run two Victron SmartSolar 100/30s and the wiring discipline alone was fiddly enough. Seventeen units must be a completely different challenge from an installation standpoint.

What's the battery bank spec to match? Presumably a substantial 48V lithium setup — curious whether that's one large bank or segmented.

@BlownFuse it's VictronConnect not VictorConnect fyi 🙃

Anyway — 117 panels is... a lot. Depending on panel wattage you'd probably want to look at whether some of those can be strung together to reduce the MPPT count. The Victron SmartSolar MPPT RS 450/200 handles higher voltages which might let you run longer strings and bring that 17 down considerably.

Also worth checking if a Fronius or similar grid-tie hybrid approach makes sense at that scale rather than going all-in on Victron MPPTs — might be cheaper per kW.

Not my usual cabin-scale stuff but I've spent enough time in Victron docs to know the RS series is where I'd start looking.

Good point from @EcoFlow_Gal on the naming there 😄

Worth considering whether you actually need 17 separate MPPTs or if the array can be reorganised. Victron's SmartSolar range goes up to the 250/100, and if your panels allow series strings of say 6-7, you might consolidate significantly depending on roof orientation and shading situations. Mixed orientations are often what force people into more controllers than they'd like.

For a system this size though, honestly the Victron Energy dealer network is your best friend — they can run proper string calculations and may suggest a hybrid approach. Have you considered whether some strings could share an MPPT if they're on the same aspect with no shading issues? That could reduce your controller count meaningfully before you even start worrying about the VE.Can bus management side of things.

What's the panel wattage and roof layout looking like?

@Lee1963 raises something worth thinking about properly. Before throwing 17 MPPTs at it, have you actually looked at the Victron SmartSolar RS 450/200? Higher voltage input means you can string more panels per controller — potentially cuts your MPPT count down significantly depending on your panel spec and roof layout.

117 panels at what wattage? That's the bit nobody's mentioned yet. A 400W panel strings very differently to a 200W one. If you're in the UK you'll also want to account for lower irradiance affecting your string sizing assumptions — we're not exactly Arizona out here.

Get your panel Voc, temperature coefficients and your worst-case cold temperature for the site sorted first. Then run it through Victron's MPPT calculator before assuming you need 17 units. You might get that number down considerably.