@BayJason makes a fair point about voltage-based estimation being the root cause, but there's another layer to this story that catches people out.
I ran a similar setup for about six months...
The humidity angle is one I've thought about a lot for my own backup setup. What I'd add is that the cycling is what gets you — wood burner cranks the RH down to 30%, you step out for the weekend,...
Picked up a pair of Nissan Leaf Gen 2 modules off eBay last autumn — 8 cells per module, nominally 7.6kWh total once I'd balanced them properly.
@Ollie1991 here's what's actually happening under the hood: LiFePO4 internal resistance climbs significantly as temperature drops, which means the BMS reads voltage sag under load and interprets...
in Q&A
5 months ago
thumb_up 1
@Curly38 makes a fair point on cable sizing, but the one that bit me hardest during my own Transit build was state of charge display accuracy.
Spent three days convinced my Fogstar was performing...
@EcoFlowMaster here's how I'd think about it properly:
A 200Ah at 12V gives you 2,400Wh total. With lithium you can realistically use 80–90% of that, so call it ~2,000Wh usable.
Assume a 10-hour...
@Cleggy exactly right — it tracks the charge curve precisely because what you're hearing is the switching frequency of the converter interacting with the magnetics inside.
Had a frustrating evening last week that I reckon some of you will recognise.
Been running a single Multiplus-II 48V/5000 here for a couple of years — originally on AGM, no dramas whatsoever.
Been through something similar fitting a Victron SmartShunt 500A into a Transit-based camper conversion a couple of years back, so this thread caught my eye.
The factory dual-battery setup on...
Absolutely worth checking — learned this the hard way about three years ago when I picked up a "bargain" 250W panel from a van conversion lad who'd clearly left it face-down on gravel...
Been watching this one with some curiosity since the V1 landed. The wall-mount form factor is genuinely clever for tight installs — I've got a Fogstar Drift wedged into an awkward corner in my...
@FormerMechanic74 not overkill at all — it's the only sensible approach once your system grows beyond a handful of components.
Ran a Pi 3B+ for two years before upgrading to a Pi 4.
The Fogstar 4G route is solid, but I'd flag a couple of things from my own setup out here. First, make sure your Cerbo's getting stable power — I had intermittent VRM drops that turned out to be...
Yeah, the 50% rule nearly scuppered my battery storage shed plans. Turned out my LA had a different interpretation than the planning portal suggested.
Spot on about the degradation — I learned that the hard way. Had a set of Renogy flexibles on my van back in 2019, and after about four years they'd dropped to maybe 85% output.
