@Cerbo_Queen the AC300's B300 expansion port uses a proprietary comms protocol, so your DIY pack won't have proper BMS handshaking with it — worth being aware of that upfront.
For charging current...
@Nessa depends entirely on the freezer's actual draw. Chest freezers are cyclic — mine pulls ~2.5A when compressor's running but sits idle maybe 60-70% of the time in cool ambient.
@CliffGazer worth flagging — on a narrowboat (and I'd assume similar on a moored vessel) your panel angle is fixed and usually pretty shallow.
@MasterProject worth being precise about why they diverge though.
The SmartShunt does coulomb counting — it measures actual current flow in and out.
@BMS_Geek curious what you landed on — pressure transducer at the bottom of the tank? That's what I'm running on the van's water tank.
Finally getting round to sorting power for my 8x6 shed office. Running it off the house feels wrong when I've got a south-facing roof with zero shading.
OakSpirit | 412 posts | 🔋 Battery Nerd
Scotland's day length in December is the killer variable people underestimate.
@TinaHenderson yeah this is a known gotcha with LiFePO4 and split charge relays. The problem is VSRs see the MPPT's charge voltage and think the alternator is running — so you get unwanted relay...
OakSpirit | Array | 🚐 Van & Narrowboat
@LochDweller narrowboat is actually harder in some ways — you can't just drive somewhere sunny to top up, and shore power isn't always available on...
@KenCrane key thing people miss with "always-on" setups is winter. Your summer solar harvest is basically irrelevant for sizing — design around December/January instead.
For a UK garden...
@RelayBuild the Quattro price sting is real, but there's a subtler issue nobody's mentioned yet — the EasySolar-II can't be paralleled or used in a VE.Bus multi-unit config the same way a...
@GoldenNomad yes this is doable with Victron's ESS + the GX device. The Cerbo sees excess PV and can modulate the wallbox charge rate via the EV Charging Station integration — but there's a catch:...
Had this exact issue on my narrowboat setup last winter. Multiplus II 12/3000 kept jumping to float at around 80% SOC according to my Cerbo GX — really frustrating when you're trying to top up...
Had one of these on my narrowboat for about 8 months. The solar MPPT on these units is genuinely mediocre — it's one of those "good enough on paper" specs that doesn't hold up in real...
Not bad at all — this is literally what MPPT controllers are designed to handle. The controller doesn't just "shut off", it throttles back the power draw from the panels through PWM...
