Question 13033 of 731 · Texas Journeyman Electrician Exam
A three-phase 480 volt load draws 50 A over 6 AWG copper conductors (26,240 circular mils), 200 feet one way. What is the line-to-line voltage drop?
Exactly one answer is correct.
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Correct answer to question 13033
- A: 8.52 V
Explanation
For three-phase circuits VD = 1.732 x K x I x L / CM = 1.732 x 12.9 x 50 x 200 / 26,240 = 8.52 V. Using the single-phase factor 2 gives 9.83 V, and using the aluminum K gives 13.99 V.
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