Case Study: Clayton Public Power improves underground feeder protection with SEL FT50 and FR12

Town of Clayton Improves Underground Feeder Protection With the SEL-FT50 and SEL-FR12

Clayton Public Power, a municipal utility in North Carolina, needed a way to keep automatic reclosing benefits for momentary overhead-line faults without repeatedly reclosing into permanent faults on underground feeder cables exiting the substation. Working with Schweitzer Engineering Laboratories (SEL), the utility looked for a protection approach for its SEL-651R advanced recloser controls that could distinguish underground from overhead faults and better protect substation equipment.

SEL implemented the SEL-FT50 and SEL-FR12 Fault Transmitter and Receiver System to send fast fault-location status to the recloser controls and block reclosing when a fault occurred on the underground section. The scheme was lab-tested, then commissioned on four feeders in about half a day, and Clayton Public Power saw it work in service when an overhead fault was cleared and the feeder reclosed normally. The solution was developed from concept to full commissioning in just a few months and improved reliability while reducing unnecessary fault-current exposure to equipment.

Clayton Public Power