Services, Grounding & BondingQuestion 31 of 120
A service uses 3/0 AWG copper ungrounded service-entrance conductors. What is the minimum size copper grounding electrode conductor?
a.4 AWG
b.6 AWG
c.2 AWG
d.1/0 AWG
Explanation
Table 250.66 groups 2/0 and 3/0 copper service conductors together and calls for a 4 AWG copper grounding electrode conductor. The 6 AWG row applies to service conductors of 1 or 1/0 AWG, 2 AWG copper is required only above 3/0 through 350 kcmil, and 1/0 applies to service conductors above 350 through 600 kcmil.
Law Reference: 2023 NEC Table 250.66Practice all 120 questions free — no signup required.
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