The Siemens SIRIUS 3RT1044-3XF00-0GA0 is a size S3 power contactor rated for 30 kW at 400 V in AC-2 duty, making it a direct fit for slip-ring motor switching or other moderate-inrush applications where the load current stays within the AC-2 curve.
At 500 V the same contactor is rated for 37 kW, and at 690 V it drops to 18.6 kW, so the voltage derating curve matters if you're running a 690 V line. The enclosure carries IP20 on the front with the cover or box terminal fitted; the terminal body itself is IP00, so it expects to live inside a panel, not out in a washdown zone.
Main circuit terminals accept solid conductors 2x (0.25 to 2.5 mm²) and stranded conductors 2x (10 to 50 mm²), plus a 2x (2.5 to 16 mm²) range for solid or stranded. That covers control wiring on the small end and power cabling up to 50 mm² on the large end — no need for adapter lugs on typical motor feeds up to that cross-section. The auxiliary contact block (not included with this base unit) would wire into the same screw terminal format.