Siemens 3RV1042-4HB10 Molded Case Circuit Breaker

Siemens 3RV1042-4HB10 Sirius motor protection circuit breaker is a three-pole molded‑case device (size S3) designed for motor protection in low‑voltage panels. It provides thermal overload (A‑release) protection in the 36 to 50 A range and short‑circuit protection with a 650 A N‑release rating, enabling motor circuits to withstand high fault currents. This unit offers motor protection up to 100 kA short‑circuit withstand, class 20 trip characteristics, and a screw-terminal connection for secure wiring; the front is IP20 rated, and the unit includes removable terminals for auxiliary and control circuits, supporting straightforward integration into Sirius MSP/MCCB configurations. Typical applications include protection and switching of three‑phase motors in machine tools, conveyors, pumps, and processing lines where compact protection and easy interface with motor starters are required. The 3RV1042‑4HB10 is part of Siemens’ Sirius family of motor protection and circuit breakers, providing increased breaking capacity and reliable coordination with protective relays and control circuits.