Question 13044 of 749 · Maryland Journeyperson Electrician Exam
A three-phase 208 volt circuit of 10 AWG copper (10,380 circular mils) supplies 25 A per phase at 120 feet one way. What is the percent voltage drop?
Exactly one answer is correct.
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Correct answer to question 13044
- D: 3.1 %
Explanation
VD = 1.732 x 12.9 x 25 x 120 / 10,380 = 6.46 V, and 6.46 / 208 = 3.1 %. Using the single-phase factor 2 gives 3.6 %, and dividing by 120 V instead of 208 V gives 5.4 %.
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