Siemens NNG3B100 U Molded Case Circuit Breaker

The Siemens NNG3B100 U molded‑case circuit breaker is a three‑pole, 600 V low‑voltage MCCB rated for 100 A, part of Siemens’ G‑frame family. It combines a thermal‑magnetic trip unit for overload protection with instantaneous magnetic trip for short‑circuit faults, delivering reliable protection for three‑phase distribution circuits. Designed for use in panelboards, distribution panels, and feeders in commercial and light‑industrial electrical systems, it supports safe, straightforward protection of motors, conveyors, and general distribution loads. The NNG3B100 U model carries the standard three‑phase configuration and a 100 A continuous rating, enabling coordination with upstream overcurrent devices in multi‑breaker installations. Typical applications include motor control circuits and power distribution feeders in HVAC and manufacturing settings, as well as general purpose protection within Siemens’ low‑voltage MCCB lineup. In environments where space and reliability matter, this 100 A MCCB provides robust short‑circuit interruption on 600 V systems while remaining compatible with Siemens’ accessories and panel systems for streamlined integration.