ABSTRACT
This chapter describes the principles of operation of all transformers, the terms step-up and step-down, and a transformer power rating based on the loads to be powered. It explains practical concerns when using transformers, the differences and similarities between single-phase and three-phase transformers, and the terms employed for transformers. The chapter presents the four different configurations for connecting three-phase transformers and efficiency of a transformer based on its daily usage data. It explores familiar tests for measuring transformer data, and the data from tests to determine transformer losses. The importance of a transformer is more pronounced for high powers, although at low-power level, there are millions of small transformers in all household and industrial products. In all transformers, one phase or three phase, the primary winding gets energy from the mains and the secondary winding is connected to the load(s).
