This is patched firmware version 281.05, based on factory firmware version 81.05, for the Axpert MAX II 8kW with a TMS320F28066 processor. It will display as 81.05 on the front display, but as 281.05 on monitoring software.
This firmware should simply not update if your inverter is the type with a TMS320F2809 DSP processor. Use only if you know that your processor is a '28066, e.g. if your main firmware from the factory was version 81.xx.
The arena reflash tool is included.
This patched firmware fixes the premature float bug, and implements PV patches to prevent the panels from being dragged down below 200 V (was 90 V). This allows the battery to fully charge from solar, and increases PV production, especially in cloudy conditions.
For upload instructions, see https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767 .
As always, use at your own risk.