Breaking capacity — what the voltage-dependent ratings mean for your fault level
This MCCB's interrupting capacity is declared at multiple system voltages, which is the correct way to spec a breaker for a given point of common coupling. At 240 V AC it interrupts 187 kA; at 415 V AC, 121 kA; at 440 V AC, 75.6 kA; at 500 V AC, 30 kA; and at 690 V AC, 17 kA. The 187 kA at 240 V covers high-fault industrial services where the transformer is close; the 121 kA at 415 V suits most European 400 V distribution boards.
Above that it derates linearly: 194 A at 55 °C, 188 A at 60 °C, 182 A at 65 °C, and 176 A at 70 °C. Power dissipation at rated load is 42 W maximum, which matters for enclosure thermal rise calculations when grouping multiple breakers.