SIRIUS Power Contactor, Size S3
The Siemens 3RT1044-1AR64 is a SIRIUS-brand power contactor in frame size S3, rated for motor loads up to 37 kW at 500 V and 18.6 kW at 690 V, 50/60 Hz. It mounts via screw and snap-on onto 35 mm or 75 mm standard DIN rail, and its screw-type main circuit terminals accept stranded conductors up to 2x 50 mm². The front face carries IP20 protection; the terminal area is IP00.
Ratings and Duty Cycles
The AC-3 (motor) switching capacity is 1000 operations per hour maximum; AC-4 (inching/plugging) is limited to 300 operations per hour. The auxiliary contacts are rated for 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V. Mechanical life is 10 million operations. Operating temperature range is -25 to +60 °C, storage -55 to +80 °C. Pollution degree 3 is specified, suitable for industrial environments with conductive pollution.
Mounting and Integration
The contactor occupies a 70 mm width, 146 mm height, and 188 mm depth footprint. Side-by-side mounting is permitted without derating, which simplifies panel layout for multi-contactor groups. The screw-type terminals accept solid conductors: 2x (0.5…1.5 mm²), 2x (0.75…2.5 mm²), max 2x (0.75…4 mm²); stranded: 2x (10…50 mm²); and solid/stranded mixed: 2x (2.5…16 mm²).