Hey we have a dicussion here in the shop. I`m wiring a machine 380 volts 3phase. Well The rated kw reads as follows 380@70kw max.
I get 2 25kva xfmers and wire per 575/380 output my total figured kva is 103. Ok that`s my total avalible if needed.Co-workers maintain I should figure wire size and ocp according to 103 but I`m only using 70 of the 103 and plan on sizing accordingly.Also now here`s one thing we`re all unclear about in the auto configuration would we say 70kw/380x1.732=106amps
or use 70kw/575x1.732=70amps? Thanks in advance.

I`m thinking that the voltage is 380 to the machine so I`m planning on going with 106amps calc. 125 ocp 1/0 wire thhn.

Look at this, it might help.

http://www.sola-hevi-duty.com/products/transformers/BuckBoost/