That 1000 A holds steady through 55 °C — at 60 °C it derates to 955 A, at 70 °C to 815 A. The interrupting ratings are substantial: 242 kA at 240 V, 187 kA at 415 V, and 74 kA at 690 V.
Trip unit and adjustability
It ships with the ETU350 electronic trip unit. That gives you adjustable long-time pickup (Ir) from 0.5 to 1.0 × rated current — so you can set it anywhere from 500 A to 1000 A. Short-time pickup (Isd) is adjustable from 1.5 to 10 × Ir, and short-time delay (tsd) from 0.04 to 0.4 seconds. Instantaneous pickup (Ii) goes up to 10 000 A. That range lets you coordinate selectively downstream without oversizing the main.
Dimensions: 320 mm high, 210 mm wide, 120 mm deep. That's a 3-pole frame, so it occupies one standard MCCB mounting position in a switchboard or panel.