The standard defines how a breaker behaves under fault conditions:

: The current a breaker can interrupt and then still remain fully functional without replacement. Rated Short-Time Withstand Current ( cap I sub c w end-sub

The IEC holds strict copyright over its standards. Distributing or downloading a free IEC 60947-2 pdf from unauthorized websites is illegal and often risky (malware, corrupted files, or outdated versions).

IEC 60947-2 is a standard published by the International Electrotechnical Commission that specifies requirements for circuit-breakers and fuses. The standard is part of a series of IEC standards for low-voltage switchgear and controlgear, and it provides a framework for the design, testing, and performance of circuit-breakers and fuses.