There is a single-phase 40A grid connection at a construction site. The site requires a three-phase 80A supply. Can I create a three-phase system using three 20kW MultiPluses, even though only one of them is connected to the 40A grid supply?
It should be possible, but how do I configure this?
The 20 kva model isn’t available yet, maybe next year.
Given that they work the same as the smaller ones, which is very likely, you can disable the option “Switch as group” when configuring your VE.Bus system through VE.Bus System Configurator
In general you can setup the three phase system with VictronConnect since its only three units, but im not sure if this option is available through the app.
ESS is not possible anymore if you disable “Switch as group”, it would work as a regular victron system though.
But keep in mind that you are still bound by the 40A single phase your grid can supply. 40A at 230V is roughly 9kW, splitting that to three phases you maybe get 2.5kW per phase on the output, including losses but no charge going to battery. That is far away from your required 80A threephase. So the remainder has to come from the battery.
If you use the possible 46kW (80A three phase supply is 55kW but we get 9kW from the grid as well) for six hours a day then thats 276kWh. Then the remaining 18hrs of the day you need to recharge at 15.3kW, which your grid does not support. Also no losses accounted for.
If you can reduce the daily work hours consumption to 150kWh then that could work. Barely, any amount of PV would help here as well.
@RikHa
The usual way to covert from 1 phase to 3 phase would be using a static phase converter. Short google reveals price appr. 1,000 EUR/kW.
Though a hybrid generator with 3x MP2 15k, a buffer battery and diesel genset would be a solution for the construction side.
Victron had white papers for hybrid gensets.
You could add one phase power supply units from telco industry or one MP2 to permanently recharge the batteries or DC-bus, though create DC-coupling. The AC-DC-AC round trip has an efficiency around 80-85%, or 15-20% loss.
Oh yes I’m fully aware off what I can draw from the 1x40A connection. It should be enough to keep the site running during 8 working hours. We are also considering a generator if batteries go flat. Thanks for your answer, I was not aware of the “Switch as group” possibility.
I know, thanks.
The problem is they don’t want generator running all the time. I will look the hybrid gensets up. Thanks.
Many consider 3+1 MP2. The 3 MP2s build an island, maybe as hybrid genset.
The 1 MP2 does permanently recharge battery and DC bus from your one phase.
The genset will run only when the 1 MP2 cannot recharge battery enough.
You can substitute the 1 MP2 bei power supply units from telecom industry. But I am not aware of units bigger than 3 kW. Maybe parallel them. They have higher efficiency than a MP2 but will not be integrate so nicely.
