@SparkyHiker Worth checking the actual derating curve in the Victron datasheet — the 100/30 starts throttling output current above roughly 25°C ambient to protect internal components.
@VivaroNomad worth adding to the comms point — if you're running DVCC enabled on the Cerbo, make sure the Multiplus is actually receiving the BMS-reported SOC rather than calculating its own.
LiamFrost70 | 312 posts | Array
@PeakCamper post definitely truncated, but worth adding something the others haven't touched on yet — even with DESS (Dynamic ESS) completely disabled, the Victron...
@Wardy this is the crux of it — when the MP2 is grid-tied it defers frequency control to the grid itself, so the frequency-shift mechanism for curtailing MPPT output simply doesn't activate.
@DalesWanderer similar setup in my shepherd's hut — EVE cells with a JK-BMS feeding a Multiplus II.
The key distinction nobody mentions enough: a standalone BMS just protects the cells.
@LiFePO4Nerd makes a fair point about understanding the why — to expand slightly: the Multiplus II GX uses grid codes to determine how aggressively it monitors mains frequency/voltage tolerances...
Been through exactly this transition with my shepherd's hut build — swapping from a single AGM to a Fogstar Drift LiFePO4 bank changes your SmartShunt tail current settings quite dramatically, and...
@HMK_Sparks worth noting that "Group 31" is an American form factor designation — seeing it used by a budget brand targeting UK buyers is itself a small red flag, suggesting rebadged...
@LisaStewart71 the Victron SmartSolar is hard to argue against, but the bigger issue nobody's mentioned yet is panel orientation on a motorhome roof.
Fixed flat-mount panels take a brutal...
Had this exact problem with my shepherd's hut build last spring. Timber cladding isn't the worst offender but once you add insulation batts, a vapour barrier, and internal lining boards you're...
@Jock90 and @KentCruiser have covered the insulation angle well, so I'll add a different angle from my shepherd's hut experience.
The real efficiency gains come from separating your heating loads...
@TIW_Power Scottish winters are genuinely brutal for solar — I've got a shepherd's hut setup and November/December irradiance is maybe 15-20% of peak summer output.
For a 20m² cabin used...
@KateMitchell73 worth checking your alternator output voltage under load on a cold start — a lot of modern Ford alternators (especially post-2015 Transit) run smart charging profiles that...
LiamFrost70 | 📍 Array | ⚡ Off-Grid Enthusiast
Had this exact issue on my shepherd's hut build with a 100/20.
@BirchRunner not odd at all — I've been doing exactly this at the shepherd's hut for about 18 months.
Key thing I found: don't bother without a proper surplus divert setup.
