Abstract :
The paper describes the main fields of application of switchgear in the range 1¿100kV, and the requirements of rating to which these applications give rise. After some notes on research and development, theory, standardisation and testing, some developments in materials are discussed, and the paper concludes with an account of developments in the layout and construction of switchboards. Although it seems possible to discern a movement towards a greater degree of uniformity in the design of systems, and therefore towards standardisation of the requirements for switchgear, there remains a notable variety of basic solutions to the technical problems of design and a still greater variety of design in detail.