Which outcome occurs when a molded case circuit breaker is subjected to repetitive short-circuit interruptions beyond its rating?

💡 Explanation

When a breaker repeatedly interrupts faults beyond its rating, contact wear increases, which diminishes interrupting capacity because arc quenching becomes less efficient, leading to lower withstand capability. Therefore, the interrupting capacity decreases, rather than increasing trip strength, faster quenching, or decreased contact resistance which don't occur with contact degradation.

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