Hi @Deepdigger, @rori1977, @darkf3d3,
I also have a SolarEdge inverter (SE2200) with a Wattnode modbus meter (WNC-3Y-400-MB) attached.
Starting with openHAB the SolarEdge Binding was one of the first I was using frequently and thus I gained a lot of experience.
If you have access to the settings of the SolarEdge inverter (and if you think you are capable to do this), you can activate the ModbusTCP interface.
I wanted to have my setup to be more accurate and a bit more independent of cloud services.
So I setup the Modbus Binding manually (see Solaredge inverter via Modbus TCP 2 - Tutorials & Examples - openHAB Community).
But in the meantime, the Modbus Binding got improved by the Sunspec Extension. This means a lot cleaner Thing overview and makes the scaling rules obsolete (that makes a plus in performance).
For the actual values like current power feed and power usage I am now using the Modbus Binding with the Sunspec extension having two things - the inverter and the meter. Update rate: 5 seconds.
For the aggregate data I am using the Solaredge Binding via public API. Update rate: 15 minutes.
Note: I am still using OH2.5, but this applies on OH3.0 as well I think.
Maybe this helps 
Jonathan