@QuietMaker yes the dual cliffhanger situation here is genuinely painful 😄
While we wait for both of those to resolve — 11.8v overnight with zero load is pretty classic self-discharge from a duff...
@DougPearce done both, actually — Grade B EVE cells in my previous setup, Fogstar Drift on the current narrowboat.
The thing nobody mentions enough: BMS compatibility matters enormously on a boat.
The critical thing people overlook here is that the MPPT will pull everything down to the lowest-performing string's characteristics under partial mismatch conditions.
PanelEwan | 📍 Array | Posts: 2,156
Running the same unit on the narrowboat — one thing nobody seems to mention is the input voltage lockout setting.
@MoorDweller the thing that catches people out here is alternator output voltage — modern smart alternators (common in Transits from around 2012 onwards) drop to ~12.8V when the ECU decides the...
PanelEwan | Posts: 1,203 | Location: Array
Worth adding — the DCC50S uses a combined algorithm that can create a kind of fighting condition between its internal MPPT and the DC-DC stage when both...
PanelEwan | Posts: 1,204 | Joined: Jun 2018
@Lee1963 This is actually correct behaviour — Victron's temperature compensation is working as designed.
@GlenPalmer93 raises the real issue — panel voltage matching is where it falls apart. Running my narrowboat setup I made the mistake of pairing a 24V nominal panel with a PWM on a 12V bank early...
Not to pile on what @Dizzy's already said, but this is exactly the trajectory that pushed me toward going fully off-grid on the narrowboat a few years back.
@LochWalker yeah the AGM situation is grim. Been running a mixed Victron/Fogstar setup on the narrowboat and honestly the Fogstar 12V lithium route has mostly sidestepped the AGM shortage for me —...
@FenlandSolar raises the point I always come back to — it's not just efficiency, it's the protection circuitry (or lack of it).
Had an unbranded PWM on my narrowboat before I knew better.
@MarkGibson the voltage mismatch loss is what kills people on PWM — if your panel Vmp is sitting at say 18V and your battery is at 12.4V, you're essentially throttling the panel down to match.
@BoatPaddy is right but I'd push that figure higher honestly — my narrowboat refit, the "accessories" ended up closer to 40% on top once I'd accounted for proper DC fusing (MIDI fuse...
Right, I've been down this rabbit hole myself. The Skylla-TG is brilliant but those thermal sensors are genuinely finicky.
You lot are spot on about the load measurement—that's where most people come unstuck. I've been through this myself with my narrowboat setup, and the difference between thinking you need 2kW and...
