I have two fronius Symo 15kVA with 36.5 kWp combined PV panels, currently connected at AC-IN, so they will be shutdown during grid outage.
In addition I have 3 Multiplus-II 3000 with 8 Pylontech US2000 48V and 4kWp via an MPPT-RS.
Everything is 3phase in my household (heat pump, oven, cooking, wallbox...).
If there is a long power outage (days to weeks) I'd like to have the possibility to rewire the fronius inverters to AC-OUT and reconfigure them to MG50 frequency shifting to also use the power that they generate.
Now my question: is it possible to use this configuration if I limit each fronius to max 4.5kW via Fronius Grid configuration? This should then be 2 x 4.5kW = 9kW distributed over 3 legs. So it should still match the factor 1.0 rule because there is never more then 3kW on AC-OUT on each of the Multiplus-II 3000.
Will frequency shifting still work in this configuration?