Unable to connect SMA Sunny Boy via Modbus/Sunspec binding


I´m trying to connect a SMA Sunny Boy to OpenHAB via Modbus/Sunspec binding. After following the insctructions of the binding I added a Modbus TCP Slave and enabled Modbus TCP at the Sunny Boy. According to this thread (SMA SunSpec over Modbus - #10 by mrbig), the default ID is 126 (tried also 3, but of course not everything between). Now the Modbus TCP slave shows “online”, but this is also the case with wrong IP… → Is there an easy way to find out if the TCP slave is really correct connected?
As the automatic discovery doesn´t work, I tried to add the “Single Phase Inverter” manually. According to SMA (https://files.sma.de/downloads/SMA-Modbus-general-TI-de-10.pdf) the adresse should 40001, but also e.g. 40000 doesn´t bring up any results → Status unknown

Does anyone have an idea or possible ways to find the mistake?

Thanks a lot and Merry Christmas :wink:

If you are having to stab in the dark about addressing etc., it’s a lot easier to experiment with some 3rd party tool like mbpoll. openHAB setting up is more suited to when you know what you want to set up, and very inconvenient for fiddling about.

Hi rossko,

thanks for the hint, I installed mbpoll and played a little around:
First thing I updated the Sunnyboy to the newest firmware. What confuses me: In another post someone uploaded a picture showing the the Modbus ID in the SunnyExplorer → This doesn´t happen at my Sunnyboy, not even after update and restart.
Anyway, the communication seems to work, find below a screenshot of the communication:

According to SMA, the first section should give me the Unit ID at adress 42109:

→ If 42109 & 42110 is serious number, 42111 SusyID, than 42112 should be the Unit ID, anyway the expected number (3) is stored in 42113…
Afterwards I used adress (Unit ID) 126 (3 + 123), communication worked, so I assumed I got the correct values (This is also in accordance with https://files.sma.de/downloads/MODBUS-DEN1516-V13web.pdf, where the adress is starting at 40001)

Does anyone has an idea at where to look next? Or a running Sunnyboy with different configuration?