TL;DR
A tandem breaker is a circuit breaker that packs two independent single-pole circuits into one panel space, each with its own handle and trip mechanism. Panels accept them only in slots the manufacturer rates for it, enforced by the rejection notching on the bus and noted on the panel label as CTL limits.
What it means
A tandem breaker is a circuit breaker that packs two independent single-pole circuits into one panel space, each with its own handle and trip mechanism. Panels accept them only in slots the manufacturer rates for it, enforced by the rejection notching on the bus and noted on the panel label as CTL limits. They legitimately free space in a crowded load center, but they cannot serve 240-volt loads and a panel full of them often signals a service that has outgrown its capacity.
Where it sits in the glossary
Tandem breaker 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
License: CC-BY-4.0 — quote freely with attribution to ProFix Editorial Team / ProFix Directory.