SIRIUS S3 Power Contactor — 22 kW AC-2, 38.2 kW AC-3
The Siemens SIRIUS 3RT1446-1AL20-ZX95 is a size S3 power contactor rated for 22 kW at 400 V in AC-2 duty (slip-ring motor starting) and 38.2 kW at 690 V in AC-3 duty (squirrel-cage motor switching). Mounting is screw-and-snap-on onto 35 mm or 75 mm standard DIN rail, with side-by-side mounting permitted — no gap required between units, which saves rail space in a crowded panel. The main current circuit uses screw-type terminals; the control circuit accepts solid conductors from 0.5 mm² up to 4 mm², and the power circuit handles stranded cable up to 50 mm² (derated to 35 mm² at 60 °C ambient). Front face is IP20 (finger-safe), terminal area is IP00 — standard for panel-mounted contactors where the buswork is behind a deadfront.
RoHS compliance date is 05/01/2012. It meets EU substance restrictions.
Integration — What Fits and What Doesn't
The S3 frame is the same footprint as other SIRIUS S3 contactors, so if you're swapping out a 3RT1044 or 3RT5045, the mounting holes and DIN-rail clips line up. The control coil voltage is not listed in this spec record — confirm the coil rating from the full order code or nameplate before wiring. If the panel sees sustained ambient above 60 °C, you'll need to derate the current-carrying capacity or move to a ventilated enclosure.