Explain why machinery used on a.c supply is usually rated
in KVA instead of KW?

Answer Posted / manugirl

t is because machinery used on ac supply are transformer regulated and the certainty that transformers are rated in KVA so as machineries used on ac supply should be given contained by KVA rating.
AC supply machines are rate in KVA . The total power consumed or supplied by the system depend up on the power factor of the load. As you know KVA= KW / Power factor.KW will cash for power factor.

Also size of a AC system is depend up on the insulation requirement (depend upon voltage) and size of conducting material( depend upon the current) so Voltage x current will give VA or Size of AC system
All AC power sources like transformers, generators, inverters etc. are usually rate in KVA.

The reason is that surrounded by the case of a power source, you cannot predict the type of load (resistive, Capacitive or Inductive) that will be connected to it. Hence the actual usable size rating depends on the power factor of the load.

Power = Voltage x Current x Power Factor

If the load is resistive, PF is 1 (unity) and if the nouns is inductive, it will be less than unity.

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