Extension of use of the maintenance-free VCB into the medium voltage GIS concept

This paper describes a new series of medium voltage gas insulated distribution switchgear which is, just as the vacuum circuit breaker which it uses, designed to be maintenance-free for its lifetime. Its use will increase the reliability, simplify and reduce the costs of operation of secondary distribution in public and industrial networks. Initially, this new series, type 8DC, is available with single busbars, for rated voltages up to 24 kV, short circuit interruption up to 25 kA and rated currents up to 1250 A. All the most common circuit arrangements are provided for. Its operation demands no particular expertise or abnormal procedures