If that is the case wouldn't they have to be very rare transformers. I mean they would have 7200 volts coming in both high side bushings opposed to 7200 on one bushing and a ground on the other. Why on earth would they even make such a transformer.
I just recently started on a new system which is completely 12470 y primary. Today a lineman told me that the system has a few delta/ delta banks. I have never heard of anyone having a delta/ delta bank on a 12470 y primary. Is this possible?