I've been at this utility for 3 years now, and my first morning here for my interview I stepped out of my Motel and looked at the Wye-Delta bank across the street and saw a cutout open on one of the power pots. This was a apartment building so I thought they were single phasing. But no utility people were around? I took a closer look and the three transformers were single bushing transformers. Will I've seen it all now. I guess years ago engineering approved the set-up. We use two bushing transformers on all new Wye-Delta banks.
Every time we have a primary feeder go down that feeds down town, we lose a s#!t load of cutouts and have a s#!t load of 3 pot, open-delta banks that we have to refuse.