What this breaker delivers
Interrupting capacity runs 121 kA at 240 V, 75.6 kA at 415 V, 25 kA at 440 V, and 11.9 kA at 690 V — the 240 V figure covers most North American panelboard fault-current scenarios, while the 415 V rating suits European 400 V distribution. Thermal derating is published per degree from 45 °C (250 A) through 70 °C (223 A); at 55 °C the continuous rating drops to 243.3 A, and at 60 °C to 236.5 A. Plan your load margin against the actual enclosure ambient, not the 40 °C reference. The N-conductor protection is rated at 100 %.
Dimensions are 158 mm high × 140 mm wide × 70 mm deep — the 140 mm width is the 4-pole footprint; a panel cut out for a 3-pole 3VA frame leaves roughly 35 mm short per pole. Verify the gland-plate knockout pattern before drilling. The front-face trip indicator is present, so fault isolation doesn't require pulling the cover.