The thermal adjustment range of 2.5...4 A means the overload element can be dialed to match the motor full-load current anywhere in that band — for a 0.55 kW motor at 230 V or a 1.1 kW motor at 400 V, for example. The magnetic trip is fixed at 78 A, so short-circuit protection clears fast on a hard fault without nuisance tripping on motor inrush. Breaking capacity is 100 kA Icu at 400/415 V AC (per IEC 60947-2), which means this breaker can safely interrupt a fault current up to 100,000 A without welding its contacts or rupturing.
This is a motor-protection device for a control panel. It mounts horizontally or vertically on 35 mm DIN rail (snap-on) or screws to a backplate with the optional adaptor. The spring-cage power terminals accept 1...6 mm² solid or 1.5...4 mm² flexible with ferrules — two wires per terminal allowed. The 45 mm width is one standard modular unit, so it fits a typical 3-phase motor branch without crowding adjacent devices.
Rated insulation voltage (Ui) is 690 V AC, impulse withstand voltage (Uimp) is 6 kV. Fire-resistance glow-wire test passes at 960 °C per IEC 60695-2-11. Climatic withstand conforms to IACS.