service for trailers

[wireman0311]

Installing 2 trailers; 100 and 200 amp service.
Utilizing a 13.8KV aerial. I assume I can use a 50KA - 13.8-120/240V XFMR. Feed a watt hour meter. Spilt and feed a 100A/SS/FU and a 200A/SS/FU.
What size feeders do I need from the secondary side of the transformer to the meter?

 

[wbd]

This sounds like a temporary feed for construction trailers??? Usually the utility company will run the secondaries (aerial overhead) to your masthead, so they will size them.