Erweiterung Victron PV Setup auf Hausboot

Slightly tangential to the thread title but relevant enough I think — been through something similar expanding a Victron setup on a static caravan, and some of the lessons probably apply to a liveaboard situation too.

When I inherited an existing Victron install (previous owner, no documentation whatsoever), the first thing I did was get VictronConnect talking to everything via Bluetooth before touching a single cable. At least then you know what firmware you're dealing with and whether components are actually communicating properly.

The bit that catches people out with expanding an existing setup is MPPT sizing. A lot of second-hand or builder-spec installs use undersized controllers because the original owner never planned to add panels. Worth checking your existing MPPT's PV input limits before assuming you can just wire in extra panels. I ran a Victron SmartSolar 100/30 and thought I could simply parallel another string — turns out the VOC headroom wasn't really there safely.

Ended up adding a second MPPT rather than replacing, which actually worked out cleaner. Two SmartSolars on the same VE.Smart network sharing battery voltage sensing behave very well together.

On the sourcing question — I've used Bimble Solar and Victron UK dealers like marinandmobile for genuine kit. Avoid anything that looks grey import; the Victron warranty situation gets murky fast.

Anyone else running dual MPPTs on a single bank here? Curious whether others have seen any balancing quirks in real-world use, especially through winter when production is patchy. My setup is land-based so a boat's partial shading from rigging etc. might add another layer of complexity.

Bit of an odd one this thread — title's in German but we're all chatting in English 😄

Done similar on my motorhome, expanding an existing Victron setup. Few things worth flagging:

• MPPT string sizing matters more than people think — don't just bolt on extra panels without checking your existing controller isn't already near its input voltage limit
• If you're adding a second MPPT, the VE.Smart Networking to sync them is genuinely worth doing
• Fogstar have decent panel deals at the moment if budget's tight

The liveaboard/static context probably means shading is more of an issue than on a vehicle too — worth considering whether separate controllers per array makes more sense than daisy-chaining everything into one.

What MPPT are you currently running @DucatoProject? That'll determine what headroom you actually have.

@Davo83 yeah noticed that too — Google Translate strikes again probably 😄

Anyway, on the actual topic — expanding a Victron setup is dead straightforward if you've planned your busbar capacity from day one. On my garden office build I made the rookie mistake of undersizing the DC busbar first time round, meant a full rewire when I added a second MPPT. Painful.

For a houseboat specifically, corrosion protection on every connection is non-negotiable — tinned cable and self-amalgamating tape on anything exposed. Moisture creeps into everything.

If you're adding a second SmartSolar, make sure both MPPTs are on the same VE.Smart network so they share battery voltage sense — massive difference in charging accuracy, especially with cable voltage drop across a longer install.

@Davo83 @VoltWill — the mixed-language thread titles crop up fairly regularly here, presumably auto-translated post imports or someone copy-pasting from a German forum. Doesn't bother me particularly.

On the substantive point about expanding Victron setups on liveaboards specifically — the one thing I'd flag that static caravan and motorhome installs often don't encounter is hull penetration management. Every additional MPPT or DC cable run potentially means another gland through the cabin top or side, and on a narrowboat especially, keeping those penetrations minimal and properly sealed is genuinely critical. I ran my second SmartSolar 100/30 internally with the array connections coming through a single weatherproofed multi-cable gland rather than separate entries. Worth planning cable routing before committing to MPPT placement, not after.

What controller is @DucatoProject actually adding to the existing setup?

@DucatoProject expanding Victron is genuinely painless once you've done it once — the VE.Can daisy-chaining means adding a second MPPT is basically plug-and-play, assuming you're not mixing SmartSolar generations (learned that the hard way on my motorhome when a mismatched firmware update had both controllers arguing like a married couple).

Key thing on a liveaboard or static setup: parallel strings need matched panels — voltage tolerances that don't matter on a van suddenly bite you when you're pulling serious amps. Fogstar do decent matched cell batches if you're expanding storage too.

Also worth enabling DVCC in Cerbo/Venus if you haven't — lets the system manage charge distribution properly across multiple MPPTs rather than them freelancing.

Great points from @MarineGeoff on the VE.Can side of things. One thing worth flagging specifically for a houseboat context — keep a close eye on your cable runs and termination quality if you're adding new MPPT controllers. Marine environments are brutal on connections, and I've seen setups where everything looked fine in VictronConnect but was quietly losing efficiency due to corroded MC4s or dodgy crimps that'd been sitting in damp bilge air. Worth going over any existing connections at the same time as expanding, rather than leaving them and assuming they're still sound. A thermal camera during a sunny afternoon can reveal a surprising amount!