CalculationsQuestion 25 of 110
A 45-kVA, 208-V, three-phase transformer has 2% impedance. What is the approximate available fault current at its secondary (infinite primary)?
a.6,245 A
b.3,120 A
c.12,500 A
d.9,000 A
Explanation
Secondary FLA = 45,000 / (1.732 x 208) = 124.9 A. Isc = 124.9 / 0.02 = 6,245 A.
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