Siemens JJ3B350 Three Phase Molded Case Circuit Breaker

Siemens JJ3B350 is a 350 A, three-phase molded-case circuit breaker in the JJ frame, rated for up to 600 V AC. It provides protection with a thermal-magnetic trip unit that includes long-time and instantaneous trip elements and carries an interrupting capacity of 25 kAIC. The unit is bolt-on mounted and uses load-side lug terminals, making it compatible with standard JJ-frame bus systems and field installation in appropriate panels. This 3P device represents the high-current end of Siemens' JJ series MCCBs, designed for heavy feeders and motor circuits where reliable short-circuit protection is required. With the JJ3B350, technicians can rely on a compact, rugged MCCB that delivers solid protection in demanding industrial environments while preserving straightforward serviceability.