Services & DistributionQuestion 4 of 521
A feeder is protected by a 100 A overcurrent device. Per Table 250.122, what is the minimum copper equipment grounding conductor (EGC)?
a.10 AWG
b.6 AWG
c.4 AWG
d.8 AWG
Explanation
Table 250.122 requires an 8 AWG copper EGC for a 100 A overcurrent device. 10 AWG serves up to 60 A, 6 AWG is for 200 A, and 4 AWG is for 300 A.
Law Reference: 2023 NEC §250.122Practice all 521 questions free — no signup required.
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