The rated voltage ratio of the transformers at no load normally is specified at 50 Hz, this being related to the principal tapping of the transformer. Tapping shall be provided on the primary winding to provide a ratio variation of +7.5% and –2.5% in steps of 2.5%. The tap charge mechanism is of the off load… Read More »
Transformer winding resistance is very important factor for the life of any transformer, this test is part of type tests, routine tests and field tests. The purpose of winding resistance test is to determine 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… Read More »
Below is the list of some important transformer tests which are conducted on site before final testing and commissioning is planned. Insulation resistance test In this test the insulation resistance is measured by applying appropriate voltage across the terminals as mentioned below: HV to Earth+LV and ground is measured with 5kV test voltage LV to… Read More »
Prior to commencement of transformer installation work, all shop drawings will be processed and submitted for approval by consulting engineer. Shop drawings will include front and side views of the equipment, overall dimensions, components identity, components type and ratings, electrical characteristics, incoming and outgoings location details among others. Plant and Equipment Following equipment and tools… Read More »
Isolation Transformers are used in order to achieve many purposes and most important of them is the safety of the transformers, equipment they are feeding and of course safety of human involved. As you are aware that transformer is electrical device that has been used to convert or transform the current or AC voltage from… Read More »
Buchholz Relay Circuit is used for Transformer Protection, as we know there are many defects and dangers during the operation of power transformer that need to be addressed and necessary measures to be taken. Some of the hazards to transformer protection include overheating, over current and short circuiting etc. Another class of fault that causes a transformer… Read More »