Re: breakers only trip once
As they say, "not so fast".....
Most of this conversation here assumes molded case breakers, and I agree with the UL testing references. It is generally understood that a molded case breaker can interrupt it rated short circuit current once(not its overcurrent trip rating) once, be able to be reset and be functional.
Switchboard rated breakers are tested and generally listed differently.
You may want to ask your specific manufacturers more detailed questions regarding this issue.
Resetting and reusing circuit breakers that have operated at their short circuit current level of higher is a risky business.
The arc flash hazards is a function of two elements. The available short circuit current and the time it takes the overcurrent device to operate. A circuit breaker that opens at more than five cycles is a real concern.
If you are in a facility that has high short circuit currents and does not maintain the breakers you are asking for trouble if you ignore the potenial arc flash hazards.
