@ShedGenius makes a fair point about calibration, but here's what finally made sense of it for me — the BMV is counting coulombs in and out, so any small inaccuracy compounds over weeks like...
@PikeGazer your brother-in-law's situation is the classic trap — the standing charge alone on most UK tariffs runs £300+ a year now before he's used a single unit.
Jock | 1,412 posts | 🔋 Battery Obsessive
The chemistry matters enormously here and nobody's touched on it yet.
Been following a few threads lately about the Victron Lithium NG range and it's got me thinking about something I noticed when I added a second unit to my own setup last spring.
My first NG 200Ah...
Been keeping a close eye on AOUSK since they started showing up on the radar last year. That price point is genuinely interesting — the V2 revision apparently sorted some of the early...
Picked up a pair of Fogstar Drift 100Ah cells back in April and wired them in parallel for a 200Ah bank in the Transit.
@CliffWill been down exactly this rabbit hole with my own LiFePO4 setup.
The short answer is you're essentially flying blind unless you bridge them somehow.
Jock | 1,203 posts
Worth knowing the JK distinguishes between charge low-temp cutoff and discharge low-temp cutoff — two separate parameters in the app.
Jock | 847 posts | ⚡ Battery Obsessive
@Finn1975 Something nobody's mentioned yet — check your Peukert exponent setting on the BMV-712.
Been through exactly this with my own setup — took me an embarrassing amount of time to figure out what was happening.
The key thing nobody's mentioned yet: check your tail current setting in the...
@SaltyTrekker the isolation alone sold it for me. Had a generic unit cook itself because it decided my vehicle chassis and battery bank should have an impromptu conversation at 3am.
@PartnerNomad yes, exactly what I ended up doing with my setup. Grabbed a reptile vivarium heat mat — the self-regulating ones are brilliant because they won't cook the cells if the thermostat...
Got me thinking about a situation I ran into last spring when I was experimenting with different charging sources on my AGM bank.
Had a DC-DC charger — a Victron Orion in my case — that was...
The frequency shift is doing exactly what it's designed to do when your battery hits absorption — the Multiplus winds up the AC frequency to throttle the Fronius back via the Fronius...
Been scratching my head over something similar with my setup, thought I'd add what I've learned.
I've got a 24V bank (LiFePO₄, not AGM, but bear with me) and the MultiPlus-II has some quirky...