Siemens 3RT1044-1BB44 Contactor

Siemens 3RT1044-1BB44 is a three-pole Sirius power contactor designed for AC-3 motor control, rated for 65 A on 400 V and capable of switching up to 30 kW at 400 V. It operates from a 24 V DC coil and provides 2 normally open plus 2 normally closed auxiliary contacts, offering flexible interlock and signaling options for control circuits. The device uses screw terminals and is sized as S3 within the 3RT Sirius family, making it suitable for compact, robust integration in industrial automation applications such as pumps, conveyors, fans, and other 3-phase motor systems. Siemens identifies this model as part of the Sirius 3RT series with a note that it is no longer available, with a preferred successor in the SIRIUS 3RT2 line (for example, 3RT2037-1KB44) recommended for new installations.