Siemens Q350U Circuit Breaker

Siemens Q350U is a 3-pole, 50-amp molded-case circuit breaker in the QP family designed for 240 V AC service, delivering a 10 kA interrupting rating for reliable short-circuit protection in residential or light commercial panels. This plug-in type QP-frame breaker is rated for common-trip operation and is compatible with Siemens QP load centers, with some variants offering Insta-Wire terminations for quicker wiring. Key specs include 240 V, 50 A, 3 poles, a 10 kA interrupt rating at 240 V, UL 489 listing, plug-in mounting, and QP-frame construction. It is widely stocked by major distributors and retailers, including Home Depot, Lowe's, Crescent Electric, and industry catalogs, reinforcing its status as a standard replacement part for Siemens Q-series panels. Typical applications include protecting feeders and branch circuits in 120/240 V multiwire systems, providing overcurrent protection for circuits up to 50 A, with a compact 3-pole footprint suitable for residential subpanels or main distribution sections within a Siemens load center. Some listings cite a plug-in footprint around 6 in W x 7 in D x 4 in H, reflecting the unit's integration in standard Siemens panels.