The co-ordination of reclosers, fuses and protection gaps

Prior to 1984 the 11 kV overhead system in the North Yorkshire District of NEEB has suffered significant disruption during abnormal weather conditions and in particular lightning. As a first stage in attempting an improvement to the system its fault performance was studied in detail and one network in particular was singled out for remedial action. The network selected was fed from Sheriff Hutton Substation and was picked on the basis of its fault history of 219 incidents and 46000 consumer hours lost over a two year period, 162 incidents being due to non damage fuse operations. The application of the new fusing and triggered gap policy on the Sheriff Hutton system produced a considerable improvement in the lightning performance with, so far, no noticeable reduction in the performance during other abnormal weather conditions