Question { 17143 }

why designer use kva rating instead of kw in transformer
rating???????????????

Answer

x'mers,UPS,DG etc are rated in KVA beacause at the time of
manufacturing manufacturer is unknown about the type of
load (inductive,capacitive or resistive)that perticular m\c
is going to suypply.so there is no question of pf to be
considerd to give it's rating in KW...........
KVA = KV X Amps -(1)
KW = KV X Amps X P.F. -(2)

it gets more clear by looking towards above formulae