Net3 node as iso

Opto isolator? I'm not sure what you mean - it's an Ethernet to DMX convertor, so you can basically pretend it's a remote 'rear face' of the console.
-The DMX ports on a Net3 DMX Gateway are optically isolated from each other and the PSU, and feature switchable termination.

All Net3 Gateways can be powered by PoE, as can the RFR Base Station.

Any PoE injector compliant with IEEE 802.3 can be used. Gateways use less than 5W of power each, so you will need to be sure that the chosen unit has a sufficient rating to supply the number of Gateways you are going to have.
(Note that early Cisco PoE may not be compatible as they created their own method before the IEEE standard was finalised)

ETC generally recommend switches with PoE built-in, simply because they are easier to install (not so many patch leads), but injectors may be better if they are being added to an existing install.

Opto isolator? I'm not sure what you mean - it's an Ethernet to DMX convertor, so you can basically pretend it's a remote 'rear face' of the console.
-The DMX ports on a Net3 DMX Gateway are optically isolated from each other and the PSU, and feature switchable termination.

All Net3 Gateways can be powered by PoE, as can the RFR Base Station.

Any PoE injector compliant with IEEE 802.3 can be used. Gateways use less than 5W of power each, so you will need to be sure that the chosen unit has a sufficient rating to supply the number of Gateways you are going to have.
(Note that early Cisco PoE may not be compatible as they created their own method before the IEEE standard was finalised)

ETC generally recommend switches with PoE built-in, simply because they are easier to install (not so many patch leads), but injectors may be better if they are being added to an existing install.