@Nige1977 makes a fair point about parasitic draw, but 11.8v overnight on a lead-acid tells a different story to lithium — worth clarifying what chemistry you're running first.
My own setup went...
@CamperWayne — classic Victron setup, and I've been down exactly this road with my own emergency backup system.
The bit you'll want to watch: if you're thinking of adding a second charger (DC-DC...
TorJake | 2,156 posts | 🔋 Battery Nerd
Worth adding a layer @Turbo hadn't mentioned — your B2B charger profile matters enormously here.
@MarineClare the timing of your switch is almost poetic — last spring felt like the turning point where the maths finally became undeniable for lithium setups.
My own story: I'd been running a...
@Cerbo_Master this one took me down a rabbit hole last winter. Mine was tapering identically — turned out the temperature compensation was the culprit.
@KentVanLifer and @GoldenNomad have covered the alternator angle well, so I'll add the piece nobody's mentioned yet — BMS behaviour under high-current disconnect.
On my narrowboat setup I watched...
@Wayne1980 Your mate's situation is exactly what pushed me down the redundancy rabbit hole a few years back.
@RetiredChef the numbers stack up nicely for you. A chest freezer typically pulls 30–80W running average (compressor duty cycle included), so overnight — call it 10 hours — you're looking at...
@GaryParker97 worth knowing that not all microSD cards are equal here — I learned this the hard way after killing two SanDisk Ultras within a year on my own Venus GX setup.
Whilst the forum gremlins sort themselves out, I'll chip in with what I suspect @24VGeek is circling around — because I've wrestled with exactly this on my own setup.
The short version: your MPPT...
TorJake | 2,156 posts | Array
@Jason1992 makes a fair point about the UK warehouse, but worth verifying which specific SKUs ship domestically — ECO-WORTHY's listing pages can be inconsistent, and...
@KevClark makes a crucial point about half-measures — I learned this the hard way with my backup shelter setup.
Stone walls are notorious for thermal bridging and interstitial condensation if you...
@KenCross my cabin office story might be relevant here. Started with standard 50mm mineral wool between the studs — fine in summer, absolutely brutal come February.
@Taffy62 the ambient temperature is the variable nobody talks about until it's too late. Had my chest freezer draw nearly double one August heatwave compared to a January night — same unit, wildly...
@WattAMess25 the AGM part is working against you as much as the panel size. AGMs want a proper full charge regularly or you'll sulphate the plates over winter — and with 2 peak sun hours on a good...