Specifications include, but are not limited to: The transformer design shall be capable of handling bi-directional power flows (step up and step down). The transformer design shall be analyzed to prove that there are no limitations on operating the transformer in the step-up or the step down direction. The design analysis shall include the transformer active part, on-load & off-load tap changers, control devices, and any other subcomponent that would have an effect on the transformer’s step-up and step-down capability. Supplier shall take an exception if the transformer ratings are different in step-up operation than the step-down ratings, the step-up ratings will be listed separately on the transformer nameplate. If the transformer step-up ratings are found to be equivalent to the step-down ratings, a statement shall be added to the nameplate indicating that the listed ratings apply to both step-up and step-down operation.