PURPOSE AND SCOPE

This is a Functional Specification for transformers and liquid filled reactors connected to the National Grid Electricity Transmission System in the UK. This specification is intended to be functional to obtain best value, encourage innovation in suppliers and support the development of new and emerging transformer technology. This specification may be used in general for quadrature boosters and phase shifting transformers but additional requirements relating to the overall performance of the units will apply. It includes coolers, cooler controls, cooler monitoring, tap-changers, ancillary equipment and auxiliary cable marshalling accommodation, and local controls and indications but not protection, automatic voltage controls or remote controls. An overview of the National Grid System is given in National Grid Technical Specification (NGTS/TS) TS 1.

Site specific requirements such as voltage ratio, impedance, rating, etc provided in a format similar to that set out in Appendix A will be included in the enquiry document. Normally these requirements will be in accordance with the standard ratings given in PS(T) 031.

Dry type reactors are covered by TS 3.3.2.