Question 13031 of 749 · Maryland Journeyperson Electrician Exam
A 120 volt single-phase branch circuit uses 12 AWG copper (6,530 circular mils), runs 100 feet one way and carries 16 A. Using K = 12.9, what is the voltage drop?
Exactly one answer is correct.
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Correct answer to question 13031
- C: 6.32 V
Explanation
VD = 2 x K x I x L / CM = 2 x 12.9 x 16 x 100 / 6,530 = 6.32 V. Leaving out the 2 gives 3.16 V, using 1.732 gives 5.47 V, and using the aluminum K of 21.2 gives 10.39 V.
More questions: Electrical Calculations
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