Why short circuit test is not performed at rated voltage?

Short circuit or Impedance test on Transformer All the readings are taken at this rated current. The ammeter reading gives primary equivalent of full load current (Isc). The voltage applied for full load current is very small as compared to rated voltage. Hence, core loss due to small applied voltage can be neglected.

Why the open circuit test is performed in the HV side and short circuit test is performed in the LV side?

The rated current in HV side is less compared to the LV side.By applying lower value of voltage than the rated value so that the rated current flows into the LV side.It is convenient to conduct the test on the HV side. Doing it on LV side reduces the rating of measuring instruments and source voltage required.

Why the open circuit test is performed in the HV side and short-circuit test is performed in the LV side?

Why in an open circuit test the HV side is open and in short-circuit test the LV side is shorted?

In short circuit test we have to pass rated current through the short circuited side. Therefore we select High Voltage (HV) side normally for short circuiting, because it’s rated current is less and therefore it is easy to short.

Why in an open circuit test the HV side is open and in short circuit test the LV side is shorted?

Why open circuit test is performed on the high voltage side whereas short circuit on the low voltage side?

In HV winding, the rated current is less than LV winding. As rated current is less on HV side, it is convenient to conduct this test on HV side by short-circuiting the LV terminals. Short circuit test can be performed on either side but generally performed on the HV side.

Why is the voltage required for short circuit test 5\%?

This is because, the voltage required for short circuit test is typically 5 per cent of the rated value. Since the current rating of HV is less than the LV, the current drawn at 5 per cent of rated voltage of HV is low.

What is short circuit test and open circuit test of transformer?

Short Circuit Test and Open Circuit Test are two important tests which are carried out on a Transformer to determine its equivalent circuit parameters, Voltage Regulation and Efficiency. Short Circuit Test of Transformer is performed on HV side and the supply voltage is so adjusted that rated current flows through the shorted secondary.

What is short-circuit test?

Important – The short-circuit test is always performed on high-voltage side i.e. the low voltage winding is always short-circuited. If the test is performed on the low-voltage winding, then, the high voltage winding being short-circuited and hence, the voltage will be inconveniently low and the current would be inconveniently high.

Why rated current flows through the shorted secondary of a transformer?

As rated current is flowing through the shorted secondary that means that rated current will also flow in the primary because of Transformer action. The supply voltage required for the flow of rated current in the shorted secondary is around 2-12\% of rated voltage.