Abstract :
The definition contained in the 14th edition of the IEE Wiring Regulations has been extended to include a wider range of electrical accessory, such as would be used for lighting, heating or power requirements in a domestic or similar type of wiring installation. No attempt has been made to cover the complete range of electrical accessories, such as those used for an industrial installation or the larger type of commercial or specialised wiring installation. The first part of the paper is devoted to a brief survey of electrical accessories that have been in use for wiring installations over the past 80 years. This is followed by a more detailed approach, dealing with accessories for specific purposes, having regard to the development of the use of electricity for performing everyday tasks. Apart from the basic design requirements to satisfy an appropriate British Standard, the factors primarily considered are those which are of interest to the user or installer of the accessory. These include safety in operation, adequate protection and enclosure of wiring connections, facility for making such connections, and general external appearance. The paper concludes with some suggestions for possible future design considerations, some of which may materially affect long-accepted practice in the use of electrical accessories.
