As with any electrical equipment,the works of efficiency usually determine from poor to excellent.How we measure the electrical efficiency?The answer is power factor.I discussed about how to sizing capacitor for  power factor correction on my last post.

Most of electrical motor or inductive equipment powered by two types of power.First is a working power.It measure in kilo watt (kW) unit.It mean this power is actually used to operated the electrical equipment.

Second is a reactive power.It mean inductive equipment need this power to  produced the necessary flux for the operation.The measurement is the kilovar ( kVAR ) unit.

So the working power (kW) and reactive power (kVAR) combined together to make up apparent power.It measure in kilo volt ampere (KVAR) unit.That is we call power factor correction. read more