It is configured as a line protection device — meaning the trip curve and accessories are set for feeder protection rather than motor or generator duty. Short-circuit withstand is the headline number here: 187 kA at 240 V, 121 kA at 415 V, and 53 kA at 690 V. Those are the interrupting ratings at the respective voltages — high enough to handle most utility-transformer-fed fault levels without cascading upstream breakers. For a 1000 A frame, that is a serious SCCR; you can place this breaker close to the service entrance and still coordinate downstream. The ETU350 release is adjustable: Ir (long-time pickup) from 0.5 to 1.0 × Iu, so 500 A to 1000 A; tr (long-time delay) from 0.5 to 17 seconds; tsd (short-time delay) from 0.04 to 0.4 seconds; and Ii (instantaneous pickup) adjustable up to 10 000 A.
At 60 °C it derates to 955 A; at 65 °C to 885 A; at 70 °C to 815 A. Dimensions: 210 mm wide (8.3 in), 320 mm tall (12.6 in), 120 mm deep. IP40 front protection.