Services, Grounding & BondingQuestion 39 of 120
A service is supplied by a single set of 500 kcmil copper ungrounded conductors. What is the minimum size copper main bonding jumper?
a.3/0 AWG
b.2 AWG
c.4 AWG
d.1/0 AWG
Explanation
The main bonding jumper is sized from the same table used for the grounded conductor and supply-side bonding jumpers, and the over 350 through 600 kcmil row calls for 1/0 copper. The 2 AWG and 4 AWG answers come from smaller service conductor rows, and 3/0 applies to much larger services.
Law Reference: 2023 NEC §250.28(D)(1)Practice all 120 questions free — no signup required.
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