TL;DR
A multiwire branch circuit is a wiring arrangement in which two hot conductors on opposite phases share one neutral, delivering two 120-volt circuits through a single cable. The NEC requires the breakers to be handle-tied or two-pole so both hots disconnect together, because a lost or overloaded shared neutral can put 240 volts across devices and start fires.
What it means
A multiwire branch circuit is a wiring arrangement in which two hot conductors on opposite phases share one neutral, delivering two 120-volt circuits through a single cable. The NEC requires the breakers to be handle-tied or two-pole so both hots disconnect together, because a lost or overloaded shared neutral can put 240 volts across devices and start fires. Common in older kitchens and dishwasher-disposal pairs, it demands care from anyone later working in those boxes.
Where it sits in the glossary
Multiwire branch circuit is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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