A Novel Reclosing Relay

This paper describes a reclosing relay for oil circuit-breaker control which is new in design, new in function, and new in operation. It was designed and built with additional features to meet certain reclosing requirements which cannot be obtained by use of standard reclosing relays. These reclosing requirements, brought about by complete automatization of high-voltage oil circuit-breakers in transmission networks and on lines containing automatic sectionalizing air-break switches, are herein described. Also several schemes of timesequence-coordination are given for the operation of oil circuit-breakers with automatic line sectionalizing air-break switches. Of special interest is a scheme for materially reducing fuse outages, which utilizes the described reclosing relay for coordinating the operations of a breaker with fuse operations on the line served by the breaker.