Circuit-breakers are used for the primary protection of medium-voltage feeders and for local protection and control near the point of load in major user installations. Radical improvements have been made to the flexibility and cost of circuit-breakers suggesting a broader range of application than has previously been possible. New equipment intended for use in cable-connection distribution networks is discussed with particular consideration to action during and following faults. New options for feeder design have arisen which allow simple, cost-effective improvements to network performance to be achieved through the installation of compact modern minimum-maintenance switchgear. A means for automatic post-fault supply restoration is described and discussed.
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