What the 25 A AC-3 rating means for your motor circuit
The 1SBL136261R2100: That AC-3 rating means it's designed for starting and stopping squirrel-cage motors — the contacts handle the inrush without welding and interrupt the running current cleanly. The 5.5 kW AC switching power figure gives you a direct motor sizing reference: a 5.5 kW three-phase motor at 400 V draws roughly 10-11 A full-load, so this contactor has margin for a single motor or a group of smaller loads. The 2.2 kW DC switching power covers DC motor or resistive loads — useful when the same panel runs both AC and DC circuits.
Mounting, wiring, and panel fit
The screw terminals accept up to 4 mm² stranded wire, which matches the 25 A rating comfortably without over-tightening the lug. IP20 means it's touch-safe once installed inside an enclosure; no special sealing for washdown areas. The 4NO contact configuration gives you four normally-open poles. That's your main power switching path; any auxiliary contacts for status feedback or interlocking need to be added separately via the AF series add-on blocks.