He found the file: EASUN_IVP_HYBRID_V4.2.1.bin . The changelog was sparse: "Fixed battery float charge bug. Improved MPPT tracking efficiency. Critical stability patch."
Before downloading random .hex files from the internet, you need to understand why you are doing this. Easun does not push automatic over-the-air updates. You must manually intervene. Common reasons include: easun firmware update
and set the Baud rate (usually 9600 or 19200, as specified in the update instructions). He found the file: EASUN_IVP_HYBRID_V4
In conclusion, my experience with the Easun firmware update has been positive. While there were some minor issues with the update process, the end result was well worth it. The new features and improvements have enhanced my overall user experience, and I'm impressed with the performance gains. Critical stability patch
Updating firmware on an Easun inverter is like updating Windows or a smartphone. There is no "rollback" button if the power goes out.
Look for or "Secondary CPU." You usually need to update both.