Services, Grounding & Bonding第 39 / 120 题
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
解析
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.
法律依据: 2023 NEC §250.28(D)(1)免费刷完整 120 道题库 — 无需注册。
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