Conditions for PV inverter assistance to go to the switch off frequency

Q&A and troubleshooting
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1

I am testing the PV Inverter assistance, to learn and understand how it exactly works, to use it at our off-grid location.
I can explain our whole setup, but I think that will only distract from the single question I have.
When does the Multiplus 2 (software version 2623556), raise the frequency to the set Disconnect frequency in the PV inverter support assistance?
The assistance starts raising the frequency at the expected Absorbtion voltage in the charger tab, but I want to make sure the PV inverter stops charging in time to overcome high voltages on the batteries. I want the last part of the charging to be only performed by the connected DC mppt chargers, as they charge more accuratly.
At the moment I raised the disconnect frequency to 0.1Hz above the standard settings, and the PV inverter shuts down nicely. It does work fine this way, but feels more like a work around.

Best regards,

Peter

2

Normally the inverter zero output power would be 52Hz, and the disconnect set at 53 - 53.5Hz

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3

I have a second hand PV inverter which operates according the VDE-AR-N 4105 grid standard. This means it limits it’s output between 50.2Hz and 51.4Hz and shuts down at 51.5Hz. At the moment I don’t see the MP2 going to 51.5Hz, to limit further charging. To mitigate this I raised the shutdown frequency to 51.6Hz, and the PV inverter shuts down nicely at 51.5Hz. This raised my question about the conditions the MP2 needs to go to the shutdown frequency.