Transformer Secondary Conductors

[fifty60]

I have a customer that wants to run conductors 50feet to a remote condensing unit. I will need to step down the voltage from my equipment via a general purpose transformer, and then run the conductors the fifty feet from my equipment.

Can someone please point me towards all of the relevant sections of NEC so that I properly size my conductors/ocpd.

 

[augie47]

240.21(C)
(be sure to read C(1) as well as the appropriate length sections--- two & delta can make a difference)