Branch Circuits & WiringQuestion 205 of 521
In a 4-wire, 3-phase wye circuit supplying nonlinear (harmonic-producing) loads, how is the neutral treated for conductor-count adjustment?
a.It is counted as a current-carrying conductor
b.It is never counted
c.It is counted as one-half
d.It counts only if it is bare
Explanation
Per 310.15(E), where the major portion of the load is nonlinear, harmonic currents load the neutral, so it must be counted as a current-carrying conductor. This differs from a balanced wye neutral, which normally is not counted.
Law Reference: 2023 NEC §310.15(E)Practice all 521 questions free — no signup required.
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