netblindpaul, thanks for asking and I have a question for you at the end of this.
At the moment no connection between inverter and PC.
No connection between inverter and router.
Inverter is directly above router, one floor higher.
PC on same floor as router but at other end of house.
Ethernet connection exists between PC and router only.
It's easy (physically) to put a cable between inverter and router.
Difficulties, converting RS232/485 signal into ethernet.
Will have RS232 to USB converter cable this week so very easy to make physical connection between inverter and router (router has USB ports) unlikely to work but worth a try.
Now it's become easier to install a serial cable between inverter and PC, serial to USB converter into PC, extend it with new cable up to inverter.
netblindpaul, do you have a link to the converters you mentioned in your post number 16?
I am thinking long term will there be drivers available for newer operating systems to allow the use of RS232 to USB converters, one I ordered will work with Win 8 so ok for now.
Even though RS232 to USB is now going to be quite easy, it might be better long term to try and get it working over ethernet.
Thanks a lot.