Answer / mahesh sali

mostly total electrical cal.in KW at 0.8 pf as per thumb
rule.

KVA = KW/PF
as per nec code norms ur dg set shall be suitable to take
the higher inrush current during starting.
so awalys keep some say 115% to 125 % on induction motor
load.
for ups & lighting system around 200 to 300 %
Toatl kw rating = 1.25 * Kw ( Plant load )
KVA at 0.8 pf = Total kw/0.8

Assume that Dg set loading at 70%
i.e rated KVA = KVA /0.7
adding some 20% future load
i.e. actual DG ser rating in KVA = rated KVA + rated KVA *
20%

Thanks

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