bruno1975

Update: Only way how to make update in my inverter, use old software "ReflashTool_Xseries" where is showing COM port is OPEN. After that i can use "ArenaINVReflashTool" and connection is established. I did update to "dsp_378.11_patched" without any other issue.
Without pre-activation with old SW (ReflashTool) i was not able to do update.

Morning i will see if phenomena with stuck at 90V gone.

Here is my comparison between 978.11 (still stuck at 90V) and 378.11
Before:

After:
Similiar full sunny morning, same time, same configuration. Change was only FW and looks much better

Here is my comparison between 978.11 (still stuck at 90V) and 378.11
Before:

After:
Similiar full sunny morning, same time, same configuration. Change was only FW and looks much better

Update (SOLVED): I have success with 978.11 firmware update. What i did extra, hard reset of inverter (battery off, AC off, PV off) and waiting few seconds.
After starting inverter with battery and AC, communication was established correctly.