Sunny Island 4.4M-11 Battery discharge / charge measurement

Hello everyone,

Maybe someone here has an idea. We have a secondary photovoltaic system. As all the companies in the region didn’t want to extend their existing PV systems, we unfortunately have a second manufacturer. As I don’t trust the figures from the app and neither of them want to / can talk to each other, I wanted to have reliable figures.

So I got a sensor for the electricity meter and started with FHEM, where SMA is not a problem, but the other manufacturer and some other things in the house are. So I ended up with Home Assistant, witch looks also a bit more modern… The new PV was solvable with googling via Modbus. Unfortunately the SMA integration doesn’t work, the 11 doesn’t have a web interface yet. The Speedwire and ready-made Modbus solutions work with the Sunny Boy, but not with the Sunny Island. After 2 days of searching, I started using Modbus.

Regarding the problem, I need a meter (Wh/kWh) for battery charging and discharging so that I can also record the in-house consumption. I give everything for the EKD system, I have the connection meter in both directions and the sunny Boy. Only the battery is missing. After a long search, I found the Excel table from SMA where my SI is also included, Modbus activated via the Sunny Explorer. I can also see the battery discharge / battery charge values in Sunny Explorer.

According to the Modbus list, the corresponding registers would be 31397 (Battery state of charge; U64; FIX0; Wh) / 31401 (Battery state of discharge;U64;FIX0;Wh), unfortunately they come back with -1 or NaN value. (Also tested with modpoll.exe -m tcp -p 502 -a 3 -r31397 -c 2 -1 -o 5 -0

Does anyone have an idea? I also found “Amp hours counter for battery charge”, but when I compare it with the nominal voltage of the battery, I only get 1362.38 kWh. Does anyone else have any ideas? Apart from reading the SI with FHEM and importing the log file into Home Assistant?

Solutions that I have already tested:

GitHub - kellerza/hassio-sma-em: Home Assistant SMA Add-On : Does not have the correct data (based on SMA-EM-Daemon – Can Sunny Boy, but does not recognise the SI. Unfortunately written in Python and not in Powershell, otherwise I would have tried an extension. Also did nothing for the SI Fork of the predecessor, great for the SB…, for this I use the
I have Speedwire user and installer passwords, and the firmware is the latest version offered by SMA. I only have no ideas more…