Answer / me

Greetings all,

iam working in an out door lighting design for our plant
and i calculated the total watt needed (sum of all lights)
= 53 kw, 220 volt

our power supply is 480V

so, I chosed a 75 KVA transformer dry type 480/220-127 V 3
phase 60 Hz

cable size from feeder to transformer primary = 50 mm2 (1/0
AWG)

cable size from transformer secondary to distribution panel
board = 125 mm2 (250 MCM)

distribution panel board main breacker = 250 A

So, are my calculations ok ? any changes or suggestions ?

thanks in advance

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