What this SIRIUS contactor is
It carries 4 normally-open main contacts and lands on a 35 mm DIN rail per EN 50022, with a screw-and-snap-on mount that fits tight enclosures — the footprint is 45 mm wide by 60 mm tall by 72 mm deep. The coil is rated for 42 V at both 50 Hz and 60 Hz, with an operating voltage range of 0.8 to 1.1 times rated at 50 Hz and 0.85 to 1.1 at 60 Hz. The main circuit uses spring-loaded terminals accepting 2x (0.25 to 2.5 mm²) solid or stranded wire, or 2x (24 to 14 AWG). The front of the terminal is rated IP20 for finger-safe access inside the panel; pollution degree 3 means it handles the conductive dust and humidity you find in a real plant room.
The AC-2 motor rating at 400 V is 4 kW — that's the load it can switch for slip-ring motors or other moderate-inductive starts. For resistive loads under AC-12 duty, the operating current maxes at 10 A. These numbers govern the fuse sizing on your schematic, not the other way around. The auxiliary contact ratings cover DC switching too: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V — useful if you're breaking DC control circuits downstream. Side-by-side mounting is allowed with a 6 mm gap to the side, so you can pack several in a row without losing rating.
The IP20 front-of-terminal rating keeps fingers out but doesn't protect against washdown; this is a dry-panel part.