Answer / jeeten jogi

transformer have 2 type of loses core n copper.core depend
on voltage n copper on current so thats y rating in kva.

Answer / santhosh a c

There are two types of losses in transformers . core losses
depends on voltage and copper losses depends on current and
one thing is power factor is independent thats y
transformer are rated in KVA not in KW

Answer / naveen chauhan

T/F have two types losss.
1.core loss - it depends on voltage & other is
2.copper loss - it depends on current
& P=V I COS(fiee) (mean depends on volt ampere). so
transformers ratings are in KVA.

Answer / sibghatullah

since transformer and generator are acting as source due to
which the load connected to them can be inductive (lagging pf)
or capacitive(leading pf) or resistive.WE don't know about
the load before hand. Real power (KW) changes due to pf
change in (P= S*pf) ,but the total apparent
power KVA remain constant. so transformer and generator
power changes that's they are rated in KVA but motor' pf is
specified and acting as a load ,that's why motor rating is
always specified in KW. because its KW never changes!!

Answer / chandrakar.amita

BECAUSE POWER FACTOR OF THE LOAD IS UNKNOWN.
AS WE KNOW
P=VI*PF
IS POWER FACTOR IS UNKNOWN THAN
P= V*I SO THE RATING WILL BE KVA

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