Inspection of Factory Transformers

The factory has transformers with a power of 16-0.1 MVA. Most of them were produced about 50 years ago, all of them are functional and used. This condition is maintained by periodic inspection of the oil quality. Each time the test result determines the time and scope of the next test. These tests constitute the Dissolved Gas Analysis DGA, which is the basis for periodic diagnosis of the condition of transformers. Oil with incorrect parameters is cleaned and retested. The article discusses the tested parameters and performs a case study of the test results of a sample transformer along with an economic calculation.