I have a very annoying problem with my off-grid setup of a Multiplus II 48-3000 and a Fronius Primo 3.0-1 PV Inverter. As soon as the Fronius connects its Power Unit through, the voltage starts oscillating from 200 to 250V and the frequency (according to my Cerbo) from 49.9 to 50.1, as you can see here: MAP001.jpg
It stays this way as long as the MP is charging the Battery (200Ah LiFePo4, no limit from the Battery Current etc.) or as long as there are no loads > 500W delivered from the battery (e.g. I turn on my heater).
As soon as the frequency rises above 50.2 Hz (when Throttling) the problem disappears, so I assume there are some regulators oscillating which parameters I can't change.
I've already tried updating the Firmware both of the Muptiplus as well as the Primo. The Primo is on the MG50 setup, the MP has the PV Assistant loaded.
I've tried to adjust the voltage between 210 and 240V, which has no effect. If there was a way to fine adjust the freqency I would do just that, as it would solve the problem to set it to 50.3 or so, as I have no clocks on the system, but there seems to be no way to set anything except 50.0 or 60.0 unfortunately - whereas with 60 Hz the issue is also there.
I'm kind of disappointed as everything works fine except this problem, which seems to also affect my batteries, because the battery current also oscillates quite much as a result, which causes problems when balancing.
Thanks so much for your help!
