The Siemens 3RT2028-1FB44-3MA0 is a SIRIUS power contactor in the S0 frame, carrying a 24 VDC coil and screw-type terminals for main and auxiliary wiring.
Motor duty and switching frequency
Rated for AC-3 motor starting, the contactor handles up to 750 operations per hour at full load, with AC-4 jogging service at 250 ops/h. Temperature range during operation is -25 to +60 °C, and storage from -55 to +80 °C.
Wiring and mounting
Main conductors accept solid or stranded wire from 1 to 10 mm². The contactor mounts on 35 mm DIN rail via screw and snap-on fastening, with ±180° rotation and ±22.5° tilt allowed on vertical surfaces. Clearance spacing: 10 mm upward/downward/forward, 6 mm to the side.