Redsy:
the term Edison 3-wire i learned about 35 years ago when I was an apprentice and it has stuck ever since.
It came originally from not sure, but in one of our appren text books was a piccture of a xfmr secondary with a center tap ergo edison 3-wire and was the term used by the instructor and it fit.
But Edison himself was a big fan of DC and his major competitor George Westinghouse was an AC proponent. Big debate bout the turn of the century, and it came down to an Execution of some murderer in NY as to use AC or DC for the kill, and it turned out they used AC and from what I remember it was decided to use AC.
I have heard 3-phase wye being called an edison but the definition just doesnt fit. Appropriately probably should be called a Westinghouse 3-wire.
