# why transformer rating is measured in KVA?

Transformer generally rated in KVA

Copper losses ( I²R)depends on Current which passing through transformer winding while Iron Losses or Core Losses or Insulation Losses depends on Voltage. That's why the Transformer Rating may be expressed in kVA,Not in kW.

The power of transformer is apparent power because it has no power factor and it is the product of voltage and current.

## Related Questions

Description : Why Transformer rating is given in kVA?

Answer : 1) The output of transformer is limited by heating due to the losses. Two types of losses in the transformer (i) Iron loss, (ii) Copper loss. 2) Iron loss depends on the transformer voltage (V). ... by load power factor. - Hence the transformer output is expressed in VA or kVA and not in kW.

Description : The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be :  (A) 34.64 kVA (B) 75 kVA (C) 20 kVA (D) None of the above

Answer : The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be : 34.64 kVA

Description : 55 When a 400Hz transformer is operated at 50Hz its KVA rating is A. Reduced to 1/8 B. Increased 8 times C. Unaffected D. Increased 64 times

Answer : A. Reduced to 1/8

Description : 4] In operating a 400hz transformer at 50Hz A. Only voltage is reduced in the same proportion as the frequency B. Only KVA rating is reduced in the same proportion as the frequency C. Both voltage and KVA rating are reduced in the same proportion as frequency D. None of the above

Answer : B. Only KVA rating is reduced in the same proportion as the frequency

Description : Define kVA rating of transformer.

Answer : kVA rating of transformer is defined as the product of voltage (V) and current (I) on primary side of transformer or secondary side of transformer divided by 1000. On both side the VA rating remains ... Mathematically kVA rating is given by, kVA rating of transformer = V1I1/1000 =V2I2/1000