Siemens NGB3B050 Three Phase Molded Case Circuit Breaker

Siemens NGB3B050B is a three‑pole molded‑case circuit breaker (MCCB) in the Siemens NGB family, designed for panelboard‑mount protection of three‑phase loads. It is rated 50 A and compatible with 600Y/347 V AC systems, providing protection for L1, L2, and L3 with a star‑connected neutral configuration. The device employs a thermal‑magnetic trip mechanism to deliver both long‑time overload protection and instantaneous short‑circuit protection, and it carries a 14 kA interrupt rating to help interrupt fault currents effectively. This NGB3B050B model is typically used in commercial and light industrial panelboards to protect feeders and branch circuits, combining Siemens‑brand reliability with compatibility within the NGB line for coordinated protective devices in a Siemens electrical distribution system. With a 600Y/347 V AC rating, it suits three‑phase feeders supplied from wye systems and aligns with common distribution practices in commercial buildings. The three‑pole design and thermal‑magnetic trip provide dependable protection for three‑phase loads while keeping installation straightforward in panelboard configurations.