What it is and where it fits
The Siemens 3RT1046-3XF00-0GA0 is a SIRIUS power contactor in the Size S3 frame, rated for motor switching at 45 kW in AC-2 duty at 400 V and 55 kW in AC-3 at 400 V. Screw-type terminals on the main circuit accept solid conductors from 2x (0.25... 2.5 mm²) up to stranded 2x (10... 50 mm²). The contactor snaps onto 35 mm or 75 mm DIN rail and measures 70 mm wide by 176 mm high by 152 mm deep — a standard panel footprint for this frame class. The front terminals carry IP20 protection, which is sufficient for finger-safe access inside a closed panel; the terminal body itself is IP00, so it expects enclosure protection from the cabinet. Pollution degree 3 means it tolerates conductive dust and humidity typical of industrial floors — no extra conformal coating needed for most plant environments.
Switching performance and thermal limits
Mechanical endurance is rated at 10 million operations typical, but the practical switching rate depends on the duty cycle: AC-1 (resistive) allows up to 900 cycles per hour, AC-3 (motor start/run) 850 per hour, AC-4 (plugging/inching) drops to 250 per hour. Arcing time runs 10 to 15 ms, with DC arc extinction taking 14 to 20 ms. The contactor handles 50 and 60 Hz supply with a voltage tolerance of 0.8 to 1.1 times rated. Ambient operating range is -25 to +60 °C; storage range extends to -55 to +80 °C. For side-by-side mounting, derate the thermal current accordingly — the 37 W power dissipation at 1000 V gives a rough heat load to factor into panel ventilation.
Auxiliary contact ratings
The integrated auxiliary contacts are rated for 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V, 6 A at 230 V, and 3 A at 400 V. These cover typical PLC input and relay coil loads; verify the inrush of the specific load against the make/break capacity at your control voltage.