Question about transformer rating

[lijojose]

in most of machines rating is in KW. but in transformers it z in KVA ...
why?

[deepaksr]

thats becoz u have to take care of power factor....

[arunbasillal]

Hey. This question was asked to me in my 3rd sem Lab viva..
Here goes the answer.

KW shows the power consumed by a machine. Transformer is not a power consuming device, its a power transfer device. So the actual power consumed depends on the load applied to the secondary. As Deepak SR said the power consumed depends on the power factor of the secondary load.

To calculate the KW rating, just multiply the KVA rating by the powerfactor if the seconday. So a 1000 KVA transformer when connected to a 0.7 pf secondary loaed used 1000*0.7= 700 KW power.. Got it..?

[manivannan.mv]

Originally Posted by deepaksr

thats becoz u have to take care of power factor....

if you don't mind please the complete explanation about mva rating in transformers