Thanks for the replies, they definitely answered some questions.
Center tapped delta is a lot more common. Usually you will see that done with 2 transformers, a big one for the single phase loads and a smaller one on the 208 "red" leg. If this is "open vee" (2 transformers) you do not want any L/L loads on the high leg. It will unbalance the phases.
I've never worked on the actual transformers for a center-tapped delta, but I've seen the diagrams, and they were always shown as a closed-delta made of three transformers. Is it more common for the actual installation to be an open-delta?
So you would install a center-tapped delta bank when you have small three-phase loads? You use a small second transformer to derive the other two phases, and then they take their large single phase loads from the one transformer with the center tap? Is that right?
It definitely makes sense that if they had three transformers they would simply make a "wye" has anyone worked on a three-transformer center-tapped delta? What were the advantages over "wye"?
-John
