That's the spec that decides whether the winding survives a jammed conveyor or pump.
Rated breaking capacity hits 100 kA at 240 V, 400 V, 500 V, and 690 V AC — that's a full-range fault-clearing capability that holds up across common industrial voltages. Rated insulation voltage spans 20 to 690 V.
Terminals accept 2× (0.5 to 1.5 mm²) or 2× (0.75 to 2.5 mm²) solid or stranded copper. The M3 screw terminals on the main contacts are what you'll torque to the values on the label — no special tools beyond a standard screwdriver. Clearance spaces: 50 mm above and below, 30 mm to the side, 0 mm forwards and backwards. That zero-clearance front and rear means it can sit flush against a backplate or a busbar shield without derating.