why the motor is rated as kw& transformer as kva

Answer Posted / r.v.giribabu

To select a rating of any equipment, Output and Input
capacity is taken as a base point.

In a motor or any other electrical equipments, conductor
size is depend on current flowing through the conductor.

size of the core (Rotor and Stator or core of a
transformer) depends on voltage as flux induced in any AC
Machine is directly proprotional to Voltage/Frequency ratio.

Which culminates to Size of equipment directly depends on
Input/Output Voltage and Current of machine. that is why
rating is mentioned as Volatage X Current i.e. KVA.

Shortly, Size of machine is directly proportinal to KVA
ratring. that is why all the electro-magnetic machines are
rated in KVA.

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