Branch Circuits & Feeders第 16 / 120 题
Where must a multiwire branch circuit have a means to simultaneously disconnect all ungrounded conductors?
a.Only where the circuit supplies more than one device on a single yoke
b.At the first outlet box on the circuit
c.At each utilization equipment location
d.At the point where the branch circuit originates
解析
Simultaneous disconnection of all ungrounded conductors is required at the point of origin, normally by handle ties or a multipole breaker in the panelboard, so no part of the shared neutral stays energized during service work. Disconnecting at the first outlet or at the equipment does not remove the hazard back at the panel, and the single-yoke rule is a separate requirement in 210.7.
法律依据: 2023 NEC §210.4(B)免费刷完整 120 道题库 — 无需注册。
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