Ignoramus31846 wrote:

Here's where I am confused. How do 240V GFCI breakers work? By
comparing currents going through two legs? If so, how can I power 120V
devices, that would naturally give off some current to neutral, and
yet not trip the GFCI?




There are two types of 240V GFCI. One only checks the current flow
between the two hots. It will trip if you try to use it with a neutral
and pull 120V off one leg. The other type includes neutral protection
and compares all the current flow. That's the one you want.