All,
I have a "old 138kv" switch yard that has 2ea 10MVA transformers in series, the first connects from the utility 138/34.5 (141.5 tap D-Y) then connects to a 34.5/7200 (33.6 tap D-D). they installed another 138kv switchyard in late 1990's and it has a 10MVA 138/6.9 (138 tap...