Question 13100 of 749 · Maryland Journeyperson Electrician Exam
A 25 kVA single-phase transformer has a 480 volt primary and a 240 volt secondary. What are the full-load primary and secondary currents?
Exactly one answer is correct.
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Correct answer to question 13100
- D: 52.1 A primary, 104.2 A secondary
Explanation
Single-phase current is kVA x 1,000 / E: 25,000 / 480 = 52.1 A and 25,000 / 240 = 104.2 A. The 1.732 factor (30.1 A and 60.1 A) does not belong in a single-phase transformer calculation.
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