Services, Grounding & BondingQuestion 49 of 120
A concrete-encased electrode may be formed by at least 20 feet of which of the following?
a.Bare 4 AWG copper conductor encased in the concrete footing
b.Bare 6 AWG copper conductor encased in the concrete footing
c.Insulated 4 AWG copper conductor run through the footing
d.Bare 8 AWG copper conductor encased in the concrete footing
Explanation
A concrete-encased electrode consists of at least 20 feet of bare copper not smaller than 4 AWG, or at least 20 feet of one-half inch or larger electrically conductive reinforcing bar, encased in at least 2 inches of concrete near the bottom of a footing in direct contact with earth. Smaller conductors do not qualify, and the copper must be bare so it can couple to the concrete.
Law Reference: 2023 NEC §250.52(A)(3)Practice all 120 questions free — no signup required.
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