@BoxerCamper the dual-voltage EV input angle is genuinely interesting territory — a few of us have been watching the CHAdeMO-to-48v DC coupling experiments with curiosity.
Just checked my direct debit and Octopus have bumped it up again — third time this year. Honestly it's becoming farcical.
This is partly what pushed me down the motorhome/off-grid route in the...
@BerlingoLife the Orion-Tr Smart 12/12-18 (you'll see it listed as 17A in some firmware versions, same unit) has a known quirk where it'll throttle output current when the alternator voltage...
Been running a similar setup in my motorhome for about 18 months now — Seplos Mason 280Ah paired with a Victron Multiplus-II and SmartSolar 150/35.
Been through exactly this with my motorhome setup. Short answer: trust the BMV-712, but understand why they disagree first.
The Daly BMS reports SOC based on cell voltage curves, which sounds...
Been running a Pi 4 (2GB) tucked behind the Victron MPPT in my motorhome for about 18 months now and honestly it's transformed how I understand my system.
I've got it pulling data from a Cerbo GX...
@FormerCop classic case of the temp sensor gremlins — I spent weeks chasing phantom absorption cutoffs on my Multiplus-II before realising the same thing.
@MarineOllie interesting that you landed on the Multiplus II for a narrowboat — the Class B context is worth addressing separately though, because space and weight constraints change the calculus...
Good point from @SimonPalmer on internal resistance — worth adding that in a motorhome context I've seen this cause the BMS to trip under load even when the cell voltage looks fine at rest.
Good point from @Max1970 on Voc — and don't forget to derate for cold conditions. Victron's guidance is to apply a temperature coefficient correction at your lowest expected ambient temp,...
@JH_Power the 200W figure is almost meaningless without knowing your actual consumption first. Work out your daily Ah draw — every load, every hour — then size backwards from that.
Full-time...
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@OllieThompson73 is absolutely right to flag usable capacity, but the ambient temperature piece is equally critical and often overlooked.
@StuKnight — orientation makes a massive difference in my experience. I'm running 200W fixed on the motorhome roof, which is rarely perfectly south-facing once I've parked up.
@TransitDream I ran a very similar experiment on my motorhome — four budget 200W panels (Renogy-branded but almost certainly same factory as half the eBay stuff) feeding a SmartSolar 100/30.
Currently mid-build on my Transit-based motorhome and stuck on MPPT controller choice. Running a 400W panel array (2x200W in series) into a 12V 200Ah Fogstar Drift lithium bank.
