CalculationsQuestion 24 of 110
For a 112.5-kVA, 208-V, three-phase transformer with 2% impedance, what is the approximate available fault current at the secondary terminals (infinite primary)?
a.6,250 A
b.20,000 A
c.10,000 A
d.15,617 A
Explanation
Secondary FLA = 112,500 / (1.732 x 208) = 312.3 A. Isc = FLA / %Z = 312.3 / 0.02 = 15,617 A.
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