He has 20 days to go ouside and clean the panels… 
Now seriously, battery is better to be > 3 times PV array size… Victron saying, not me: AC-coupling and the Factor 1.0 rule [Victron Energy]
Usually, when not following this rule could appear overvoltages on batteries when close to 100% on sunny days, because the inverter is not so quick at regulating voltages. But this is another story…
I think he has 4-6 month to clean the pv panels.
My experience with snow is:
Cleaning snow from my PV array with an elevation of less than 10 degrees takes much more effort and time than my other PV array with an elevation of around 30 degrees. But that is the key to success, i.e. to PV energy!
So, a moderate PV array matching the inverter dimensions and a diesel generator for the very dark and snowy days is more cost-effective. A big battery is everytime a good thing but it costs.
His 4 kWh diesel generator must start after the “20+” days. One hour ~4kWh (without taking losses into account).
5 h → 20 kWh into the battery, 10h … 40 kWh, … The question is, what is more annoying, 1 hour per day or 10 hours in one go over 7 days…
Question: The PV power goes to the MPPTs and then to the battery, not AC coupled.
The MPPTs should limit the PV power above SOC 90%.
I would start rethinking PV with the place you mount the panels.
Is it all rooftop? Then think about a snow clearing system.
Can you wall mount vertically below the roof overhang in direction south, that’s perfect. No snow on the panels and the snow on ground will mirror the light onto the panels.
In this case you can use one 2kWp 4-in-1-micro grid inverter per phase. The MP2 can charge the surplus energy to the battery. It will control the micro grid inverters via frequency shifting.
If you mount on free land, consider elevated vertical mounting. If you really get only 2hrs of sun light, face them to the sun. With 8hrs bi-facial panels eat/west mounted would be preferred.
Think about using a recent air condition. These are are-to-air heat pumps start working at negative Celsius temperatures. Starting in March many April you will have more PV energy you can use with those huge PV system.
Your generator is a 3 piston Kubota industrial motor. Think about a combined generator/heating system which uses the generated heat to heat your cabin.
If you want to go with Victron and split phase the system would be;
- 2x MultiPlus 2 3000 Inverter/Charger
- 2x RS 450/200 PV charger (40 panels, 5 per tracker)
- 1x RS 450/100 PV charger (10 panels, 5 per tracker)
- 2x 4-in-1 micro grid in better (8 panels) wall mounted
- Ekrano GX
- 4x Lynx Distributor or build a custom DC bus bar.
I recommend a 6x 16 kWh (314 AH) rack mounded batteries with proven compatible BMS that can be parametrized. You can extend later if needed. Some BMS support up to 16 batteries in one stack.
You can charge LFP at 1C, e.g. a 316Ah battery at 314A, but most BMS will not allow more than 200A. You need around 600-800A.
6x314=1.884 though 800A would less than 0.5C.
Each rack battery has a high of 6 units. Heavy duty shelfs will take another 2 units. Though you get 6 batteries into one 42 u rack. Or you get a person to weld a special rack. Might be cheaper.
Plan an air condition and maybe heating for your battery room. The room should be kept between 5C and 30C.
If you this huge system, you can any loads for summer time, e.g. air condition, dish washer, cloths dryer, electric stove.
I have a 8.5kWp system in northern Germany with lots of shadow. It produces up to 40kWh/day.
If we build our small water adventure park with slides and pools Max energy I can waste is 50kWh/day. You will probably produce 250-350kWh/day during summer.
Thank you for the info, I will take a note of the Victron setup you posted…
The solar panels will be ground mounted on a solar farm on tilted mounts, to tilt them 20° degrees in the summer, and 80° degrees in winter.
For the inverter, why do you prefer the MultiPlus II 3000 over the MultiPlus-II 48/15000/200-100 230V ?
You do not want to isolate the AC draw appliances from the DC draw devices?…
Should I separate the AC loads from the DC loads on different inverters? Meaning, the higher output appliances (washer machine, refrigerator, freezer, water pump, water heater) put on the main MultiPlus II AC inverter. And, the smaller electronic loads (Starlink mini, laptops, smartphones) put on the DC to DC inverters - 2 Victron Orion-Tr Smart 48/12-30A (360W) Isolated DC-DC Converter ORI481238120 (720W in total) in parallel operation and load balancing to distribute devices evenly across both converters to avoid overloading ?
For batteries, Coremax has 20 kWh 48v/400ah per unit - Coremax 48v 400ah LiFePo4 20 kwh battery storage System. RS485 CAN ports. SKU: CMX48100W-20 kwh
I will be having built a underground insulated ICF root cellar at least 10 feet under ground that will also be heated with solar powered air heater at least 75 degrees Fahrenheit from Artica Solar. It will be fully independent from the battery bank. Built over the root cellar will be a multi-purpose utility shed to house the diesel generator. The batteries and inverters will be down in the heated insulated root cellar below the frost line. The insulated utility shed will have a wood stove in there to warm it up in case there is any issues with the diesel generator.
I could be wrong but, the Victron MultiPlus II 48/15000 (15kW) PMP483150000 and the Victron SmartSolar MPPT RS 450/200-MC4 (SCC145120510) are not competitors, they serve two different functions that complement each other together. So, I would have to buy both.
I need an inverter and I also need MPPT controllers.
To simplify below, for 48.3kw solar output…
2 Victron MultiPlus II 48/15000 (15kW) PMP483150000. $5,100
4 Victron SmartSolar MPPT RS 450/200-MC4 (SCC145120510) $8,528
2 Victron Orion-Tr 48/12-30A (360W) Isolated DC-DC Converter (720W) total for smaller electronics. $488
1 Victron Energy Cerbo GX MK2 $248
or, alternative…
10 Victron SmartSolar MPPT 250/100-Tr VE Can controllers $6,130
Total with RS450/200 MC4 combo: $14,364
Total with 250/100-Tr VE combo: $11,966
Either way, that’s WAY too much. Victron needs to do something about their inverter and MPPT situation where they make you buy lots of MPPT controllers and complicate things with lots of wiring and you have a wall of a lot of blue boxes. It’s unacceptable.
I unterstood:
you need 120V split phase. Only option is two MP2 3k 120V.
Your max power demand is around 4kW.
Than 2x 3000VA (2,4kW) is enough.
If you can go with single phase 240V, than take an MP2 between 5k and 15k.
MP2s can paralleled up to 3 phase 180kVA.
The MP2 can transform AC to DC and back.
It can serve your AC loads from battery/DC bus.
It can power your DC bus or charge batteries from AC-PV and generator.
The RS/MPPT will manage your PV panels and provide energy directly to the DC bus for battery charging or transformation to AC by MP2.
General rules with Victron are:
- Serve your base load with AC-PV e.g. Fronius if grid connected. Offgrid any grid inverter featured frequency/power function works.
- Cover your peak loads with an MP2 from battery.
- Use RS/MPPT PC chargers to charge your battery.
If you can specify your requirements precisely, we can help better:
- 1, spli or 3 phase
- Voltage
- AC peak load
To be honest, your system seems to be very special and with the size and special conditions I highly recommend to ask an experienced system designer and installer.
With regards to the Victron MultiPlus II 48/15000 (15kW) PMP483150000, can it run in parallel operation with a second MultiPlus II 48/1500 or does it need an external AC transfer switch ?
There are some tricky solutions with daisychaining the inverters on the AC side, but i recommend to contact a trained installer in your area and a visit at your site to do some measurements and for further design.
Important is a small DC coupled PV for blackstart in the winter (south wall) due to an failed generator.
In an 100% off-grid solution, you do not need transfer switch.
On AC_in is the generator without grids code.
You can parallel up to 4 MP2 per phase, but only same kind.
The MP2 15k is 240V.
If you need 120V, the 3k is the only model afaik
He is saying that 3000VA seems to be the only power available for one device with double (2x) 120V outputs.
Otherwise you need to use two single (1x) 120V devices.
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Thanks for the clarification.
I’m not familiar with 2x 120V outputs models, guessed the topic owner will build a system like EU 3 phase (3 units 400VAC) => US 2 phase (2 units 240VAC).
Does Victron offer an inverter 120V 48V configured for North America that is as powerful as the EG4 12000XP Off-Grid Inverter V2 IV-15000-XP-IN-01 (15KW) or Sol-Ark 15K-2P-N (Limitless 15K-LV) ?
No, it doesn’t…
The biggest is Quatro 10kVA. And it’s not split phase.
You guys in NA are limited (from what I know) to EG4, Sol-Ark, MPP-Solar and Enphase which are built with your grid necessities in mind.
I’ll have to wait for Victron to offer a more powerful inverter or wait for EG4, Sol Ark or some other company to offer a inverter that has a lower idle draw.
EG4 and Sol Ark are powerful, they don’t need external MPPT controllers but, they have very high idle draw. That idle draw is so high it wears down the battery making the diesel generator turn on sooner increasing fuel costs. Their idle draw is higher in kwh in a single day than the refrigerator and freezer combined.
Victron has the quality and lowest idle draw but, I think their disadvantage is they make you buy many MPPT controllers which quickly increases the cost of the setup.
Indeed…
But also Victron has idle about AS the refrigerator and freezer combined. 
And the bigger the inverter, the bigger the idle consumption…
But with as much panels as you planed, that will not be a problem.
Even with other companies inverters and even on cloudy, 1 panel will cover the inverter idle consumption.
Remember, 800W panel, with 10% production (so 80W) in cloudy day covers the inverter idle consumption.
Do you really need that 120V? Your not connected to the grid so you can build as you want.
The bigger consumers (fridge freezer pump) can run on 240V.
All smaller electronic stuff & ledlights can be on DC.
While reading was asking this question to myself …
MP2 10k with 120V output can be built on order as per the datasheet.
But i personally would use a regular 230V MP2, set it to 60Hz 240V and then use a transformer to get 2x120V/240V splitphase output.
The 2x120 model does only output one 120V phase when running on inverter, check the manual for how it works internally
Well… It seems that I was the one in error… Sorry.
I didn’t use it and by looking at the selection guide posted in the picture before, one could be lead to believe that it’s a really true 2x120V, when comparing with the others in the same selection…
Well… That’s a real disappointing thing… From both marketing and technical point of view…
And, from the manual, the justification is pretty lame…
“Any 240V loads will therefore be supplied only when the inverter/charger is supplied by a split-phase AC source.
This prevents heavy loads such as water heaters or 240V air conditioners from discharging the battery.”
No need to be sorry. I only know this because this question has come up a few times already, ive never used a 2x120 myself.
The justification is marketings way of selling a potential flaw/shortcoming, but i mean, its not wrong