Rickflorida
New member
Dear Mike or forum, I am a Inspector in Afghanistan presently and have a question about short cicuit studies or KA ratings. We have several locations where we have a distribution sytem consisting of MDP downstream to a SDP and further downstream to a Cdp. The breaker feeding the sdp has a 25ka rating, the main breaker in the sdp has a 22ka rating, then the sub feed breaker in the sdp feeds the cdp the sub feed breaker is a 10ka breaker and the main in the cdp is 22ka. The question is without having all the information conductor size lenth transformer ratings, impedience could you come to a determination that this is a life health and safety issue. We have researched Nec 110-09, 110-10, 240-86 and have not came up with a simple answer as they may not be one.