Throttling AC-coupled solar too hard

Q&A and troubleshooting
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I’ve noticed that the Cerbo is throttling my Fronius inverters too hard when I’ve disabled “AC-coupled PV - feed in excess”, to the point that the Multiplus-II isn’t charging anywhere near it’s full capacity from the available PV. PV is on the AC-In side of the Multiplus-II.

For example, right now, I have about 5.5kW of solar outside - but with ESS set to “Optimised without Battery Life” and disabling excess PV feed-in, the Multiplus-II will charge the battery at around ~1.8kW, with the Fronius inverters throttled by the Cerbo down to keep the grid export as close to zero as possible (so as not to be charged for exporting).

If I switch feed-in excess back on, I’ll get ~3.3kW of charging, which is what my solar is able to supply.

I could live with a few hundred kW or something like that, but we’re talking 1.5kW of power going to waste. Is this expected behaviour or is there configuration I can adjust to get better efficiency from the throttling here? I don’t want to waste precious kW of charging when I am getting free power from the sun.

Thanks,

Andrew

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To add - I notice that I normally leave my “Minimum SOC” at 5% - I’m happy to run my battery down each night if need be - this throttling is an issue. If I change my “minimum SOC” to, say, 100%, it’ll charge at full capacity and utilise all the available solar.

So it feels like I’m running into some “expected behaviour”, but I can’t make sense of why the system would choose to not charge at full capacity if sufficient solar exists to do so.