Fronius AC coupled on Quattro Micro-grid

Q&A and troubleshooting
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1

Hello there, this post regards a curiosity rather than a concern.
I have 2 Fronius Symo 5kVA string inverters AC coupled to the AC1 out of a 3-Phase Victron Micro-Grid formed via 3 X Quatto 48V 5000/70 inverter-chargers and a Cerbo GX (running latest firmware - Dec 2024). The VE.Bus system had the PV Inverter Assistant loaded during configuration and the 2 Fronius units are setup in Country Code: MG50 configuration. There is approx 84kWh of LiFePO storage DC coupled via Lynx DC Bus system.
My experience is that system control is good and throttling of the 2 Fronius units works well as the batteries are approaching 100% SOC. However, during throttling I also note 2 things that I am curious about please:
(1) Cerbo GX still displays the status of the 2 Fronius inverters as “Running”, and not “Running (Throttled)”, as per State table in the Victron Energy “AC Coupled PV with Fronius PV Inverters” document. Has the State reporting been modified in the Cerbox GX firmware?

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and
(2) during throttling, the Fronius LCD panel throws up the State Code 560 (which Cerbo GX also reports), indicating raised grid frequency. I recognise that frequency shift is intentionally being imposed by the Victron system as the throttling mechanism and Fronius is detecting and responding to this by throttling output, all as is intended. But given Fronius is actually in MG50 configuration, why does it throw up this Error State and not just put up a message indicating that output is being throttled to prevent battery over-charging or similar?
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thank you

2

Just an educated guess:

The state Running vs Running (Throttled) is only used to indicate throttling done through modbus tcp, i.e. for fronius 0-feedin control.

When raising the frequency, the system is not aware, that a certain (or all) inverters are throttled, as this basically just implies a “upper limit” on production, without knowing if a inverter would be able to exceed that (really throttled) or just not have enough solar, therefore beeing able to run at 100% momentary power but not exceeding the “50% max power cap” .

Makes sence?

3

Yes, and thank you. I did not realise that Running (Throttled) only has meaning through Modbus.