ABSTRACT
Reliable delivery of electric power is, in great part, dependent on the reliable operation of power transformers in the electric power system. Power transformer reliability is enhanced considerably by a well-written test plan, which should include speci–cations for transformer tests. Developing a test plan with e›ective test speci–cations is a joint e›ort between manufacturers and users of power transformers. e written test plan and speci–cations should consider the anticipated operating environment of the transformer, including factors such as atmospheric conditions, types of grounding, and exposure to lightning and switching transients. In addition to nominal rating information, special ratings for impedance, sound level, or other requirements should be considered in the test plan and included in the speci–cations. Selection of appropriate tests and the speci–cation of correct test levels, which ensure transformer reliability in service, are important parts of this joint e›ort.
