After watching JW Solar's tutorials on YouTube, I've set up Home Assistant to collect the data from my Solax Inverter.
I now have a "card" on the dashboard of HA that looks to record only Solar PV generated, unlike the Solax Portal Daily Yield which cross-pollinates the data with battery power.
Today was quite a good day. The HA Solar production graph looks to be roughly the same as the Solax PV Power graph which is pleasing
I'm going to hold off posting my results on PV Output until I've done some more testing
From Home Assistant
From Solax PV Power