Schneider Electric Square D QOB350 Circuit Breaker

Schneider Electric’s Square D QOB350 is a 50-amp, three-pole miniature circuit breaker designed for bolt-on mounting in Square D QO/QOB panelboards. It is rated for 120/240 V AC with a 10 kA short‑circuit interrupt rating, and provides three‑pole protection with common trip for multi‑wire and three‑phase circuits in commercial or light‑industrial installations. The QOB350 uses a thermal/magnetic trip mechanism for reliable overload and fault protection, and its bolt‑on configuration secures to standard bus assemblies in compatible panels. This 3P device is intended for 240 VAC operation and is commonly used to protect feeders or branch circuits in panels requiring 50 A protection across three poles, aligning with Schneider Electric’s QO family in bolt‑on form factors. As part of the Square D line, it is designed to fit the mounting pattern and electrical characteristics of QO/QOB panels, enabling coordinated protection in commercial distribution setups and ensuring simultaneous disconnection of all three poles when an overload or fault occurs.