Lifetime is not really determined by the number of trips although most new breakers should have a mean time to failure in the hundreds if not thousands of trips.
The lifetime is determined more by the breakers operating temperature. Like the difference between a breaker that is loaded to capacity vs a lightly used one. One that trips occasionally theoretically due to overload will last longer than one than the breaker that always works hard and loaded to 99% of capacity.
Breakers that are tripped several times in short succession; usually a frustrated homeowner that doesnt reduce the excessive load or remedy the fault and just runs to the panel to reset the breaker. Breakers worked this way suffer internal damage and are prone to tripping on weaker loads than rated.
One thing to keep in mind, as told by my electrician, is that breakers are only guaranteed by manufacturer to open at their maximum rating once in their lifetime. After such an event, the manufacture should recalibrate it. That doesnt mean it cant open again for identically sized loads, its just that most manufacturers usually wont stand behind this.
Finally, older breakers had to deal with a smaller amount of available current from the utility, common to the time period of installation. The is the AIC rating: ampere interrupting capacity. Utilities upgraded their distribution systems and with that, make more current available and breakers can be exposed this, requiring higher AIC rated breakers. Worst case scenario is a catastrophic failure of the breaker or explosion in the panel.
Realistically, only an electrician can give you the correct answer after doing a survey of your panel.
Facebook
Twitter