Thanks for ur reply my frnd..
But i gotta too many gonna answer them pls..
consider the case i am having 10 DB`s each having 100A incomer MCB..and these DB`S ll be fed from SDP(Sub distribution Panel). where this SDP and the some other SDP`s (consider same size, say 10 each) connected to the MDB ( Main Distribution Board.).
Consider this is a Domestic load and load voltage 230/400V, 50Hz.

Here is my Questions…

1. What Kind of Breakers we have to choose for each level(from DB- SDP – to MDB)??

2. What ll be the KA ratings for all these breakers (Incomer and Branches) ???

3. Is there any calculation behind this, choosing breakers and its KA ratings??? there any Space Factors we have have to consider, when we are making all these panels???

5.Give me list of Busbar Sizes to carry all these for each level…

ThX n Advance,