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@Nef
Electricians, can you help explain calculating PFC? It seems to keep popping up as I need to use it to confirm the size of the CPC with the adiabatic equation.
I thought PFC = U/Zs, but with the examples we've been given, the answers are a bit different.
Also, when we did testing, PFC was either PEFC or PSC - whichever was higher. When you're designing, are you just working off PEFC as it's the CPC size I'm trying to confirm?
Say you have a building with 3 phase coming to a DB, which supplies a second 3 phase DB, which supplies a single phase DB - how do I go about calculating PFC at the single phase DB at the end?
EG:
3 Phase DB (A)--------3 Phase DB (B)------Single Phase DB (C)----
Zs@DB=0.09, 0.11, ?
PFC=5kA, 3.7kA, ?
I'm selecting equipment for a planned extension, so all the values for the single phase DB (C) and it's supply etc will be based off calculation.