Power Contactor for Motor and Resistive Loads
The Siemens 3RT1044-1BW44 is a SIRIUS power contactor in size S3, rated for switching motor loads up to 37 kW at 500 V AC-3 and 18.6 kW at 690 V AC-3. For heavy-duty jogging or inching duty at AC-4, it handles 55 A at 400 V. The main circuit uses screw-type terminals, accepting stranded conductors up to 2x 50 mm². It mounts via screw or snap-on onto 35 mm or 75 mm standard mounting rail, and supports side-by-side mounting for dense panel layouts. The enclosure is rated IP20 on the front with cover or box terminal; the terminal itself is IP00. Pollution degree 3 means it's suited for industrial environments with conductive pollution, typical for control panels in manufacturing lines. Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C.
Mechanical and Electrical Ratings
Mechanical life is typical 10 million operations. Maximum switching rates: 1000 cycles/hour at AC-1 and AC-3, 400 cycles/hour at AC-2, and 300 cycles/hour at AC-4. Arcing time is 10-15 ms; DC operating time is 14-20 ms. Dimensions: 146 mm height, 70 mm width, 201 mm depth. The depth is a key fit dimension for enclosure depth planning.
Compliance and Approvals
RoHS compliance date is 05/01/2012, indicating the part meets EU RoHS substance restrictions. The evidence does not list UL, CSA, or IEC certifications for this specific order code, but as a SIRIUS power contactor it is typically designed to IEC 60947-4-1 standards.