Services, Grounding & Bonding第 57 / 120 题
On the load side of the service disconnecting means, what is the general rule for using the grounded neutral conductor to ground equipment enclosures?
a.It is permitted only in dwelling units
b.It is permitted if the neutral is at least 6 AWG copper
c.It is permitted in any panelboard fed from the service
d.It is not permitted; a separate equipment grounding conductor must be used
解析
Downstream of the service disconnect the neutral and the equipment grounding conductor must be kept separate so that normal load current does not travel on enclosures and raceways. Bonding them together at a subpanel creates parallel neutral paths and objectionable current, and neither conductor size nor occupancy type changes this general prohibition.
法律依据: 2023 NEC §250.142(B)免费刷完整 120 道题库 — 无需注册。
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