I’m in Ukraine. You may know that we’re currently experiencing serious power outages—one hour on, then five hours off. Therefore, it’s crucial for me to quickly recharge my batteries (Pylontec US2000C 6 pcs).
I have a three-phase 10-kilowatt grid, or 3.3 kW per phase. Currently, the other two phases are simply not being used. Here’s what I have installed: one Victron Multiplus II 48/5000/70 inverter connected to one phase. All loads are also connected to this line.
I plan to install two more Multiplus II 48/5000/70 inverters (one for each phase) to simultaneously charge a single battery bank at a higher current.
My question: is it possible to combine all three AC outputs into one line to achieve a combined output power? …really hope for your help.
If it is just for charge power then put them into charger only mode when needed (use the generator start stop or something like it with node red) and do not bother programming them as one system such as three phase or parallel. It will be simpler especially if you get a phase down.
If it is just as a charger then it only needs AC input (no output wiring) and a connection to the battery bank or system bus bar.
Thanks for the reply!
The suggestion to use server power supplies will likely be the easiest to implement.
Do they allow you to precisely regulate the charging current? I haven’t figured that out yet.
Yes, I wanted to simultaneously increase the AC output power, as I was currently only using single-phase power (3.3 kW). I realized I’d have to redesign the distribution board to distribute the load across three lines.
I know some three-phase inverters have a load asymmetry feature, which means the same power is drawn from the grid on each phase, even if the output loads are different. Does Victron have this feature?
Remote control would be more interesting, though, as there are situations where it’s inappropriate to continue charging if the sun is about to set. Overall, this is new to me and very interesting. Thanks, I’ll try to figure it out.
If you want the system to behave as 3phase 3x 5kVA when charging and as 15kVA single phase when inverting, then no.
The cleanest way to achieve such a goal would be to use 3x 5kVA in 3phase setup as chargers and a single 10kVA unit (or 2x 5kVA in parallel) as single phase inverter.
Costs of such a system would quickly go up.
The best option would be a standard 3x 5kVA 3phase system where you spread the loads over the inverters/chargers.
I’m from Ukraine too and understand you very well.
The best approach is to buy two separate chargers (one per free phase), such as the Huawei R4875G1, because it can operate on 85-300 V AC input.
From time to time, our grid can drop less than 180V, so MPII can’t use it.
Then configure charges to change the battery by voltage or add some controllers as @kr0815 proposed to manage them using Node-Red.
Hi Vladyslav, nice to meet you here! Thanks for the tip; it’s very useful to be able to charge your device with any AC input voltage. But the fact is that it is still unknown to me, I have only come across it.
At the same time, I am also considering the purchase of two more VMPII inverters, because this will allow me to increase the power of the entire system.
But here’s what’s interesting: When you ask the AI whether it’s possible to get one total output from three phases, it stubbornly continues to say that it’s possible. It advises asking the following questions:
"How to configure three MultiPlus-II in parallel on a single phase?"
"Parallel connection of outputs (AC-Out) for single phase operation"
"Can I sync three different input phases into one output phase?"
"Phase shift settings in VE.Configure"
Do you guys think this AI is flattering, or is it possible that it can still be done? May be just need to study Vісtron’s capabilities more deeply…
"Syncing L2 and L3 to L1 phase angle" — Синхронізація кута фаз L2 і L3 відносно L1.
Not possible. The three phases are defined by their 120° angle between them. Otherwise it woud simply be a single phase. Which of course is possible, but as a parallel config. You cant get both with the same three inverters without rewiring and changing the system config through VE.BusQuickConfigure
It doesn’t matter how much power you have if you can’t charge your batteries.
First, need to resolve the battery‑charging issue using a separate charger or by charging from PV (MPPT). After that, you can increase the system’s power and battery capacity.
But here’s what’s interesting: When you ask the AI whether it’s possible to get one total output from three phases, it stubbornly continues to say that it’s possible. It advises asking the following questions:
"How to configure three MultiPlus-II in parallel on a single phase?"
"Parallel connection of outputs (AC-Out) for single phase operation""Can I sync three different input phases into one output phase?"
"Phase shift settings in VE.Configure"
Do you guys think this AI is flattering, or is it possible that it can still be done? May be just need to study Vісtron’s capabilities more deeply…
"Syncing L2 and L3 to L1 phase angle" — Синхронізація кута фаз L2 і L3 відносно L1.
I can charge batteries (300 Ah), but I would like to do it faster. Now I barely manage to return the energy reserve spent in 4-5 hours, while I have to limit myself in consumption. Therefore, I come to the idea that in the end I will have to purchase two additional PMIIs, as well as charging from Huawei in case of undervoltage at the AC input.