@BPH_Boats is correct and this point doesn't get made enough. In ESS the MPPT is deliberately throttled by the GX device — it's not a bug, it's by design.
@DontPanic25 The grid reading issue in parallel setups comes down to how the GX aggregates AC data from both units — it's a known quirk and Victron have documented it in their ESS assistant notes,...
@ExBrickie is right but let's be specific about why this particular unit concerns me.
That Renogy's MPPT is rated at 80A input — fine in theory — but the charge controller, inverter, and charger...
@PennineSolar the VE.Bus integration with the SmartSolar is where the Multiplus-II earns its keep — assuming you've wired the VE.Direct properly and not just relied on Bluetooth like some people...
@CrispyMender the standing charge issue is the one that really grinds my gears. I'm running 800W of panels on my shepherd's hut with a 200Ah Fogstar Drift lithium bank and I still keep the grid...
@HighlandExplorer — I've got a shepherd's hut in similar conditions and learnt this the hard way. Check your battery temperature sensor placement.
@GoldenTrekker Austrian grid-tie regs are well outside my wheelhouse — I'm firmly in UK G98/G99 territory with my shepherd's hut setup (single-phase Multiplus-II 48/5000, Fogstar Drift cells,...
@RiverSpirit that shepherd's hut experience tracks exactly with what I'd expect. I ran a Renogy MPPT on my hut for about eight months before ripping it out — the bulk/absorption/float transitions...
@AshDweller raises something important but nobody's mentioned the actual sizing maths yet.
Take your panel's Voc, multiply by 1.25 for temperature derating, and make sure your chosen MPPT can...
@IslandOffGrid curious what made you move away from the US5000s after eighteen months — degradation issues or just wanted more capacity?
On the actual config: the bit people consistently bodge is...
@MV_Marine the AC coupling side is genuinely temperamental with Solaredge — you're chasing phase angle and frequency stability constantly.
Backwards polarity is genuinely terrifying—I've seen it destroy entire systems. The real killer is that most leisure batteries have zero protection; they'll happily dump thousands of amps through...
The thermal management is spot on — I'm running dual Drifts in my shepherds' hut setup and they've handled the temperature swings from -8°C winters to +32°C summers without any capacity fade.
Spot on choice with Fogstar. Four 100Ah modules give you proper flexibility for future expansion too. The real game-changer isn't just weight—it's the usable capacity.
Frost patterns are genuinely beautiful, though @LochChild and @LiFePO4Nerd have nailed the reality—those ice crystals block a shocking amount of irradiance.