Miniature motor control centres

Early in 1987, the Central Electricity Generating Board (CEGB) established a contract for the provision of motor control centres (MCCs) for Sizewell B Power Station. The first stage of the contract covered the design of the MCCs. On its satisfactory completion, further stages covering manufacture, supply, installation and commissioning would be activated. As the SNUPPS design for the power station had been adopted, space for switchgear was very much at a premium. Essentially the requirement was to produce motor control equipment which was 50% smaller than previous designs without any significant relaxation in specification. It must also be capable of seismic qualification to onerous levels. These fundamental changes were the reason this contract was placed much earlier than other similar contracts. This paper details the development of the MCCs. Problem areas in the development and the solutions to them are considered. The merits of a collaborative approach to the design by the client, manufacturer and other interested parties are identified. (Author)