In a multiwire branch circuit, all conductors must originate from the same panelboard. Which of the following best describes this requirement?

• A. All conductors must originate from the same panelboard
• B. Conductors may originate from different panels
• C. Grounded conductors may originate separately
• D. Only ungrounded conductors are restricted

Answer: (A)

In a multiwire branch circuit, two hot conductors share a neutral, so it’s crucial that all conductors come from a single panelboard. This arrangement allows a single disconnect to simultaneously interrupt all ungrounded conductors (and the shared neutral), ensuring there’s no part of the circuit left energized when you shut off the power. If the conductors came from different panelboards, you could end up with an unsafe condition where one panel remains energized or where the neutral could carry current back through another panel. The neutral (grounded conductor) is part of the same shared circuit and isn’t allowed to originate separately from a different panel. In short, the requirement exists to guarantee a common disconnect and safe, predictable de-energization of the entire MWBC.