Theory & SafetyQuestion 115 of 120
What is the secondary full-load current of a 25 kVA single-phase transformer with a 240-volt secondary?
a.Approximately 60 amperes
b.Approximately 104 amperes
c.Approximately 208 amperes
d.Approximately 52 amperes
Explanation
For a single-phase transformer, I = VA / E = 25,000 / 240, or about 104 amperes. The 60-ampere answer divides by 480 volts, 208 amperes divides by 120 volts, and 52 amperes is half the correct value.
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