Services & DistributionQuestion 68 of 521
At a grounded AC service, the grounded (neutral) conductor run to the service disconnecting means must be sized:
a.Only large enough to carry the neutral load
b.The same as the equipment grounding conductor
c.No smaller than 6 AWG copper in all cases
d.Not smaller than required by Table 250.102(C)(1) and never less than the neutral load
Explanation
Per 250.24(C), the grounded conductor brought to the service must be at least the size shown in Table 250.102(C)(1) (based on the ungrounded conductors), and also not smaller than needed to carry the neutral load. Sizing it only for neutral load can leave it too small to serve as the effective fault-current path.
Law Reference: 2023 NEC §250.24Practice all 521 questions free — no signup required.
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