AIC rating compatibility

[samiam]

In search of guidance regarding the compatibility of AIC ratings between bussing and breakers. I want to know whether the rating of the panel/switchboard is the limiting factor. Example: If I took 65kAIC rated breakers could I put them into a 50kAIC rated enclosure? If so would the available fault current have to be calculated not to exceed the bracing of the enclosure' bussing, in this instance 50kAIC? If there is no code issue, that neither the breaker nor the boards bracing are necesssarily incompatiable then which defines the limits of the other and why?
Your collective wisdom will be much appreciated.

 

[charlie b]

Re: AIC rating compatibility

The lower of the two is what determines the rating. You got that part right. The applicable section is 408 (2002 version). I could not find any rule that says that the rating of the breaker and the rating of the panel have to be the same. However, the available fault current has to be lower than either of the other two.