Why are motor ratings given in KW and that of alternator and transformer given in KVA?

Why are motor ratings given in KW and that of alternator and transformer given in KVA?
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1 Answer

Answer :

kW is the output mechanical power of a motor and is expressed in kW.
kVA is the net (apparent) power input to the transformer. This input power is the output + losses.
kW = kVA x system power factor
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