Services & DistributionQuestion 101 of 521
For a feeder/service neutral, the portion of the maximum unbalanced load that exceeds 200 A may generally be calculated at:
a.50%
b.80%
c.70%
d.100%
Explanation
Per 220.61(B)(2), the neutral load in excess of 200 A may be taken at 70% (subject to the restrictions of 220.61(C), such as nonlinear loads). The first 200 A is at 100%; the other percentages do not match the code demand factor.
Law Reference: 2023 NEC §220.61Practice all 521 questions free — no signup required.
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