A short circuit test is performed on a transformer to determine its impedance, losses, and temperature rise. This test is done by short circuiting the secondary winding of the transformer and applying a low voltage to the primary winding.

• Transformer Rating: 400/200V


• PU Impedance: 0.05

The short circuit voltage of a transformer is the voltage that appears across the secondary winding when the primary winding is short-circuited. It is given by the formula:
Short Circuit Voltage = Rated Voltage / % Impedance
Here, the % Impedance is given in terms of p.u. (per unit).

So, the short circuit voltage of the given transformer can be calculated as:
Short Circuit Voltage = 400V / 0.05 = 8000V

Therefore, to perform the short circuit test on this transformer, a voltage of 8000V should be applied to the primary winding while the secondary winding is short-circuited.


In conclusion, to determine the short circuit impedance of a 400/200V transformer with a p.u impedance of 0.05, a voltage of 8000V should be applied to the primary winding during the short circuit test. This test is important to determine the losses and temperature rise of the transformer.