scope:

PURPOSE AND SCOPE

The National Grid (NG) Technical Specification for metal-oxide surge arresters is primarily by reference to BS EN 60099-4 and defines the required enabling parameters and additional technical requirements for surge arresters connected to and rated for use on the NG UK Electricity Transmission System 132 kV, 275 kV, 400 kV and other lower voltage systems.

This document specifies the requirements for substation surge arresters of the following type: open terminal (AIS) porcelain, polymeric, integrated polymeric housed and gas insulated (GIS) systems connected directly between phase-and-earth of the NG UK Electricity Transmission System. It supports the more general requirements defined in the companion documents TS 1, TS 2.1 and TS 2.2.

Informative: Special applications for surge arresters (series compensation, MSCDN, transmission line arresters etc) will not be covered in this specification. While the general elements of this specification maybe used, the application specification will provide the functional performance requirements.