Siemens HED43B045U

Siemens HED43B045U is a 3-pole molded-case circuit breaker rated for 45 A at 480 V, part of Siemens’ HED4 MCCB family. It provides thermal-magnetic protection for three-phase circuits, making it suitable for protecting feeders, panelboards, and motor-control applications in industrial and commercial environments. The device carries a 42 kA short-circuit current rating at 480 V, indicating its ability to interrupt fault currents and safeguard wiring and equipment. Designed for operation in typical 40°C ambient conditions, the HED43B045U offers compact, reliable protection in space-constrained panels and distributes across three phases with consistent trip characteristics. This model is widely documented in Siemens and distributor listings under the HED43B045 family, confirming its 45 A, 480 V, 3P specification and its role in safeguarding 3-phase electrical distribution.