Being that he only has single phase gen input he has no option but to run a pair of inverters in split phase configuration, parallel is only going to give him a set of 120v legs that aren’t properly phased for 240v split phase use.
the only other way around that is to use a transformer but as far as the victron lineup goes, even the largest 100amp transformer is limited to 28amp when using it to convert single phase to split phase. Maybe there’s some better options out there from other suppliers but honestly I don’t think it’s the best route to take
As far as I’m aware if you were to use a pair of multiplus single phase units set up in a split phase configuration you still get your full 70amp per unit of charging (140 total).
If my brain is on right tonight, if you’re looking to pull 30a 240v off of that single phase 8000w gen, your ev charger alone is going to take everything it’s got, with little to nothing left over for charging RV batteries while it runs so I think I’d call that kind of a moot point. Once the ev is charged there is tons of power left over for both inverters to charge the RV batteries (appx 2kw) and still run whatever you want inside the RV
No doubt if he HAS to have 240 split phase then he has no choice but to run 2 multi’s in split phase with his single phase generator, but he is NOT going to get 30 amps or even 20 amps split phase for very long (running generator) before the L2 inverter starts getting hot and derating anyway, and you surely wouldn’t want to do that on strictly battery power. I would suggest giving up the idea of charging the ev at a high rate on split phase when off grid, just not practical in this situation.
If using 2 multi’s in split phase the ONLY time you will get a full 140 amps dc charging is when connected to 50amp split phase shore power. When connected to single phase shore power or running the generator, only L1 will pass thru and supply battery charging and L2 will be inverting.
Of course there are some exceptions if a transformer is also installed but that is another costly expense and it has its own limitations.
Very true, those things would have to be extremely well vented , as with the generator as everything would be running at full load to have any hopes of supplying 30a 240v power. But like he said, he can always adjust the EV to charge at a lower rate.
I guess from there a guys gotta look at what’s practical. Are you going to really gain anything with all this added expense to go split phase only to reduce the charge rate to accommodate its limitations, or just charge the EV on 120v (assuming that’s an option)
Maybe money is better spent towards a generator that offers 120/240 split phase… thats undoubtably the more expensive route but really the best option if this is intended to be used frequently