The interrupting capacity is 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — these are the fault-clearing ratings that determine whether this breaker coordinates with upstream gear and safely interrupts a short circuit without rupturing the enclosure. At 240 V, 187 kA puts it in the high-interrupting tier for a 20 A frame; at 690 V the 17 kA figure is the binding limit for three-phase 690 V distribution.
For a 20 A MCCB, these are high enough to coordinate with a 200 A or 400 A upstream SENTRON 3VA frame in most industrial distributions — the ratio of interrupting capacities gives the upstream breaker time to clear before the downstream device reaches its let-through.