It is rated 40 A at 30 °C ambient with a Type B tripping characteristic, meaning it trips instantaneously on short-circuit and on overcurrent with a curve that allows moderate inrush without nuisance trips. The unit is designed for 50 Hz, 230/240 V AC supply and carries a breaking capacity of 6 kA per EN 60898 and 10 kA per IEC 60947-2.
The 40 A rating is at 30 °C; the unit derates to 37.6 A at 40 °C, 36.4 A at 45 °C, 34.8 A at 50 °C, 32.4 A at 55 °C and 60 °C, 30.8 A at 65 °C, and 29.2 A at 70 °C. This derating curve is critical for panel builders — if your enclosure runs warm, the effective current capacity drops. It mounts in any position and accepts supply from either top or bottom, which simplifies wiring in tight cabinets. The test circuit requires a minimum of 195 V to function.