SIRIUS S2 Coupling Contactor – 3RT2035-3KB44-3MA0
The Siemens 3RT2035-3KB44-3MA0 is a SIRIUS S2 coupling contactor designed for switching loads in control panels and motor circuits. It mounts on a 35 mm DIN rail per DIN EN 60715, with screw and snap-on fastening, and can be rotated ±180° on a vertical surface or tilted ±22.5° forward/backward. The coil is rated 24 VDC, drawing a peak inrush of 2.6 A, with spring-type terminals for the magnet coil. Main contacts are rated for 18 to 1 A range.
The AC-1 (resistive load) switching frequency maxes at 1,200 operations per hour, while AC-3 (squirrel-cage motor starting) allows 1,000 ops/h. AC-4 (plugging/reversing) drops to 300 ops/h — the duty cycle governs how hard you can push it in reversing or inching applications. At 24 V rated value, the contactor switches 6 A; at 230 V it handles 7.5 hp. Arcing time runs 10 to 20 ms, and the dropout delay on DC is 30 to 55 ms — useful timing data if you're coordinating with a safety relay or PLC output sequence.
The contactor measures 55 mm wide, 114 mm high, and 178 mm deep. The S2 frame size is a common footprint in Siemens SIRIUS lineups — fits alongside overload relays and busbar systems in a standard 55 mm-wide slot. Spring-type terminals accept 2x (0.5 to 2.5 mm²) solid or stranded wire — no ferrule needed for solid, but stranded benefits from a ferrule for reliable cage grip.
This part is in current lifecycle stage.