I’m still debating which Victron Multiplus I should get.
I have a Minisplit 115 volt model.
I have 1720 watt total on my roof (solar) 41 volt panels and 11 amp. And 50 amp service.
So with only 12 volt stuff (none 24 volt) but with 41 volt solar panels (1720 watt total) and a 50 amp rv service hookup. Should I be better off with a Multiplus 2 2x120 or multiplus 2 24/3000..??
The Multi 2 2x120 is a single 120 volt inverter but has two 120 volt AC paths. One L1 connects to the inverter when 120/240 shore power is available, but the inverter does feed both output legs when no AC is present. The 2x120 will also accommodate 120 volt 30 amp service. In this regard, it's well suited to RVs with 120/240 volt 50 amp service.
The Multiplus 2 24/3000 is a single unit and would be more difficult to adapt for 120/240 volt AC input, although you could run two units in split phase then add an autotransformer ahead of it to make 120/240 power from 120 volt single phase.
If you go with a 24 volt battery bank for the inverter and the solar chargers, you will need to make 12 volts for your RV DC devices. You would need to size the DC-DC converter to your maximum load. If you run the fridge on DC, that will probably be your biggest single load (100-200 watts for an absorption fridge). (If you run it on AC or propane, the draw is tiny. Slides take a lot of power also. Then the heater, bathroom and range hood fans. Assuming LED lighting, there probably aren't any other big 12 volt consumers.
1 more question: If i install my panels 2p2s and so have 2 arrays of 860watt (1720 total) with (41volt and 11 amp panels)
So I will use 2 charge controllers, do I need Victron 150/85 or will 150/70 be sufficient? And should I install a solar breaker in between panels and charge controller?
Thank you
1700 solar watts is 140 amps at 12 volts and 70 at 24. You'd be into a very expensive controller like the 250/100 and still need two of them for 12 volts. The current rating of the Victron MPPT controllers is the OUTPUT current. So the 150/85 or 150/70 would work for 24 volts but you would need to split your solar array and use two of them for 12 volts.
with 41 volts open circuit, I'd recommend a 150 volt controller to be safe at low temperatures.
Hard one to answer from an inverter side. I am guessing costing is what it would come down to.
1720w on 12v needs a charge controller (or two) to fully use them as it will be 143Amps potential.
Whereas 24 volt system you only need just over 70 amps mppt. So from solar yeild side it makes sense to go with higher battery voltage.
Also you will need smaller DC cabling.
@Oerske if all your load is 12V as described, also add in the cost of sufficient DC:DC 24 to 12V capacity.
