Question 1051 of 749 · Maryland Journeyperson Electrician Exam
On a wye system serving many computers and LED drivers, which harmonics add together in the neutral instead of canceling?
Exactly one answer is correct.
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Correct answer to question 1051
- B: Triplen harmonics such as the 3rd and 9th
Explanation
Nonlinear loads produce harmonic currents. Odd multiples of the 3rd harmonic are in phase on all three phases, so they add in the shared neutral and can overload it.
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