Fronius: Improve detection of 3-phase inverters using SolarApi

[izak]

At the moment this relies on detecting the Device Type from a list provided by Fronius.

It already causes problems for the GEN24 and the Tauro, which has the same DT, but the GEN24 isn't 3-phase while the Tauro is. SolarAPI document says we should not rely on DT for the GEN24 and Tauro.

Further, every time Fronius brings out a new model, we will fall back to detecting it as a single phase unknown model.

Therefore, attempt to detect phase config a bit better.

Possible solution Idea: Calling /solar_api/v1/GetInverterRealtimeData.cgi?Scope=Device&DataCollection=3PInverterData&DeviceId=1 returns an empty dictionary on single phase inverters.

The SolarAPI document is here. It contains an incomplete list of DT values, going backwards from 254 and down to 67 in this document, though obviously many models are not on this list and causing incorrect solarapi operation in the field.

[Wholistic]

I am also seeing an uptick in complaints about this - would be nice to have resolved by 3.2 in line with the Sunspec improvements

https://community.victronenergy.com/questions/241155/displaying-fronius-on-ccgx.html

[izak]

The thing about this whole thing: There is an easy solution. Turn on Sunspec on the inverter. It is even documented. Though understandably people may not have read all the documentation or even know where all of it is.

There are also a small hand full of cases where people cannot or will not use Sunspec, and we did also create a situation where Fronius inverters usually work "out of the box", we should keep that.

[izak]

Got information from Fronius for the missing DeviceTypes.