The Siemens 3RA2346-8XB30-1NB3 is a pre-assembled SIRIUS reversing contactor assembly, size S3, that combines two 3RT2046-1NB30 contactors with mechanical interlocking in one package. It reverses a three-phase motor by swapping two phases, controlled via a single coil circuit. Rated at 45 kW at 400 V AC-3 (75 hp at 460/480 V), it handles the full motor current in both directions without external wiring of the reversing pair.
The S3 footprint measures 150 mm wide by 160 mm tall by 152 mm deep — allow 10 mm clearance above, below, and to the sides for airflow and wiring access; zero clearance needed at the rear.
Main power circuit and coil connections use screw-type terminals. Each pole accepts two conductors: solid or stranded 0.5–1.5 mm² or 0.75–2.5 mm². The coil draws 3.1 VA at both 50 and 60 Hz, operates on 20–33 V DC, and is rated for 850 switching cycles per hour at AC-3 maximum load.