Testing of Windings - Insulation and Mechanical Strength
This includes four types of tests, that we have described briefly in Table .
Table : Testing of Windings
We provide below the findings of the Central Power Research Institute (CPRI) about the short circuit test.
Box 1: Findings of Central Power Research Institute on Short Circuit Test
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From the available data on short circuit tests, it seems in which the failure rate of transformers manufactured through small and medium scale industries is at par along with those of large scale industries. But in practice the rate of failure is extremely high. The reason could be that the materials used for bulk manufacture of transformers are not the similar as those used for the transformer generates for testing reasons. This is a distinct possibility since the materials cost contributes a main share to transformer cost. Manufacturers use inferior quality materials to bring down the cost to compete in the highly competitive market. Therefore, there is a requirement for proper quality assurance at the manufacturing stage even though the prototype has successfully passed the Short Circuit Test.
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