The peak value of an impulse voltage that the equipment can withstand without insulation failure. It measures the breaker's ability to survive atmospheric overvoltages (like lightning strikes). Rated Ultimate Short-Circuit Breaking Capacity (Icu)
The primary goal of IEC 60947-2 is to ensure that circuit breakers can safely interrupt short-circuit currents and protect industrial power distribution systems up to 1,000V AC or 1,500V DC. It applies to equipment operated by skilled personnel rather than general consumers. Key Technical Characteristics iec 60947-2 pdf
While high-level summaries provide a foundational overview, accessing the actual official IEC 60947-2 PDF document is essential for design compliance. The full document provides exact time-current characteristic curve boundaries, detailed environmental testing tolerances, and the mandatory testing sequences that manufacturers must abide by. The peak value of an impulse voltage that