[sungrow] added Backup Current/Power registers

[stl01]

No description provided.

[soenkekueper]

Hey,
thanks for your contribution!

I've checked the sungrow-spec, which this addon was based on, and could not find any information about the backup registers, do you have a newer version?
When trying to read the registers manually i get a read error - this would cause openhab to read no data :/
So my question is, which kind of sungrow inverter are you using, that this is working on?
I'll build and try what happens, but think it would break compatibility to some other inverters.

Thanks for the correction of energy register - i think this is actually wrong within the documentation.
As i'm using the DAILY_EXPORT_ENERGY channel i've not remarked this issue - is this channel working for you too?

BR

Sönke

[stl01]

Hey, sorry for this rather uncommented and blank PR. I'm not too familiar with the git workflow.

I'm using a Sungrow SH10RT-V112 and a SBR128 Battery with a permanent load on the backup line. In this setup I get the correct values in Watt over the specified input registers. I don't know if these are implemented in other inverters as well.

The backup registers and 4 other register (Meter Active Power Total and for each Phase) are not documented in the sungrow-spec as far as I know. I found this information here:
https://www.photovoltaikforum.com/thread/166134-daten-lesen-vom-sungrow-wechselrichtern-modbus/?postID=2645527#post2645527

another great source for the sungrow input and holding registers is this Home Assistant integration
https://github.com/mkaiser/Sungrow-SHx-Inverter-Modbus-Home-Assistant/blob/bf94a1f215c3b67de28347c8cc5d61fe327242f4/modbus_sungrow.yaml#L311

The DAILY_EXPORT_ENERGY_FROM_PV is indeed just wrong in the sungrow documentation. The last days were not sunny enough for me to export any meaningful amount of energy so that I could not check or understand the logic and the difference to the DAILY_EXPORT_ENERGY channel. But I've seen a 0,1 kWh twice on both channels so that I know that it is at least technically working.

Since this PR I was working on the four Meter Active Power registers and a decomposition/decoding of the Running State (13001) and System State (13000) Registers. That's why they were also added as comments in the code.

Do you know if it's possible to read/write holding registers with this addon?

BR
stl01