OK, I have still not found a single GFCI breaker that is 240V/3Ph!
There are plenty under 50 A ( max required by NEC ), but they are all for 208V systems, which automatically means 208/120 Wye with Neutral.
Does anyone have any links to a true GFCI device for Delta services?
From what I saw, at this time NEC only requires GFCI for :
L-Ground voltages below 150V
Current of 50A or less for single phase, 100A or less for 3 phase
Receptacle connections only ( hard wired connections do not require GFCI )
Thanks for that info. In Germany the power from the street is 400 V 3 phase. The GFCI breaker is installed right after the meter and it monitors all loads powered by that electrical service. I repeat "ALL" loads, including welders. I also have a 25 KW 400 V generator in a container that feeds my house and shop as well as my neighbor's house. That generator also uses two separate GFCI breakers. one for each load. This arraignment works fine and covers all loads wye, delta, single phase, receptacles or hard wired. Only one breaker is required per power feed. It works well. These are installed at the junction box containing separate bus bars for all 3 phases , neutral and safety earth and where the bond between safety earth and neutral is made.