Transformer Testing | Type Tests and Routine Tests of Transformer

For confirming the specifications and performances of an electrical power transformer it has to go through a number of testing procedures. Some tests are done at a transformer manufacturer premises before delivering the transformer. Transformer manufacturers perform two main types of transformer testing – type test of transformer and routine test of transformer. Some transformer … Read more

Open and Short Circuit Test of Transformer

Open and short circuit tests are performed on a transformer to determine the: Equivalent circuit of transformer Voltage regulation of transformer Efficiency of transformer The power required for open circuit tests and short circuit tests on a transformer is equal to the power loss occurring in the transformer. Open Circuit Test on Transformer The connection … Read more

Transformer Polarity Test

Current flows from high voltage point to low voltage point due to the potential difference between them. Here, electrical polarity comes into the picture. Electrical polarity simply describes the direction of the current flow. When we look into DC system, we find that one pole is always positive and the other one is always negative … Read more

Sweep Frequency Response Analysis Test | SFRA Test

This is very reliable and sensitive method or tool for condition monitoring of the physical condition of transformer windings. The winding of transformer may be subjected to mechanical stresses during transportation, heavy short circuit faults, transient switching impulses and lightening impulses etc. These mechanical stresses may cause displacement of transformer windings from their position and … Read more

Winding Resistance Test of Transformer

A winding resistance test of a transformer is carried out as a type test, routine test and also as a field test. In the factory, it helps in determining the following: Calculation of the I2R losses in transformer. Calculation of winding temperature at the end of temperature rise test of transformer. As a benchmark for … Read more

Voltage and Turn Ratio Test of Transformer

Transformer Ratio Test The performance of a transformer largely depends upon perfection of specific turns or voltage ratio of transformer. So transformer ration test is an essential type test of transformer. The voltage should be applied only in the high voltage winding in order to avoid unsafe voltage. Ratio Test of Transformer and Check of … Read more

Vector Group Test of Power Transformer

Vector Group Test of Transformer The vector group of transformer is an essential property for successful parallel operation of transformers. Hence every electrical power transformer must undergo through vector group test of transformer at factory site for ensuring the customer specified vector group of transformer. The phase sequence or the order in which the phases … Read more

Insulation Dielectric Test of Transformer

The dielectric test of transformer is generally performed in two different steps, likewise, separate source voltage withstand test and induced voltage withstand test of transformer, which we have discussed one by one below. Separate Source Voltage Withstand Test of Transformer This dielectric test is intended to check the the ability of main insulation to earth … Read more

Temperature Rise Test of Transformer

A temperature rise test of a transformer is an important test which should be included in any type test of an oil transformer. In this test, we check whether the temperature rising limit of the transformer winding and transformer oil is as specified by the manufacturer. Temperature Rise Test for Top Oil of Transformer First, … Read more

Impulse Test of Transformer

Lighting is a common phenomenon in transmission lines because of their tall height. This lightning stroke on the line conductor causes impulse voltage. The terminal equipment of transmission line such as power transformer then experiences this lightning impulse voltages. Again during all kind of online switching operation in the system, there will be switching impulses … Read more