Branch Circuits & FeedersQuestion 16 of 120
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
Explanation
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.
Law Reference: 2023 NEC §210.4(B)Practice all 120 questions free — no signup required.
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