How many bolted faults can a residential circuit breaker withstand?
How many licks does it take to get to the center of a tootsie pop is rather unanswerable. How many faults are they built to withstand and still be functional, should I swap them out after X # of faults, and are they more likely to fail-dangerous if they're old and abused?



According to the UL, a breaker must safely clear its maximum current twice and still be functional. This is a manufacturing standard; not really your concern unless yours broke after the first fault.

CBs are built to always fail-safe. An older breaker that seems to nuisance trip more often than it should might be grounds for replacement and it's probably the easiest way to see if there is something funny going on but there's no reason to arbitrarily replace them after a few faults. Several thousand faults? you'd better check what's going on and that breaker goes in the garbage on principle.

I'm unaware of any UL testing that seeks to show a reset count limit. I'd assume the possibility of a fail-on state is negligible or it wouldn't be UL'ed. IME, when they break they just don't reset anymore. - Find me an un-safe one and we'll go sue 'em for all they've got.