Siemens HGB3B040 Three Phase Molded Case Circuit Breaker

Siemens HGB3B040B is a three-pole, low-voltage molded‑case circuit breaker (MCCB) in Siemens’ HGB family, rated 40 A for three‑phase circuits up to 480 VAC, with a 35 kA short‑circuit interrupt rating. It employs a thermal‑magnetic trip unit that provides overload protection and rapid fault current interruption across all three poles, making it suitable for panelboard installations and equipment feeders in industrial environments. By design, it ensures common-trip protection so all phases disconnect together during a fault, simplifying wiring and enhancing safety in 480V distribution schemes. The HGB3B040B designation identifies the 3P, 40A configuration within Siemens’ molded‑case lineup, offering a compact, rugged solution for low‑voltage, three‑phase protection in commercial and industrial facilities.