Question 13045 of 790 · California General Electrician Exam
A 120 volt, 20 A load is 150 feet from the panel. What is the smallest copper conductor that keeps voltage drop at or below 3 %?
Exactly one answer is correct.
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Correct answer to question 13045
- A: 6 AWG
Explanation
Allowed drop is 3.6 V, so CM = 2 x 12.9 x 20 x 150 / 3.6 = 21,500 circular mils. 8 AWG has only 16,510 circular mils, so 6 AWG (26,240) is the minimum; 12 AWG would be sized for ampacity alone.
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