Best Practices to Mitigate Temporary Faults on Overhead Distribution Systems

Project Summary:

New feeder distribution technologies are being developed to help mitigate temporary faults. These technologies utilize automatic switching principles to detect and interrupt faults, while automatically determining if the fault is temporary or permanent. This allows for fewer customer interruptions, better temporary fault identification, and fewer manual reclosing operations needed to be performed by linemen crews (which can lead to higher outage times). DSTAR P16-3 summarizes current activities by DSTAR and non-DSTAR utility members across North America, highlighting best practices and lessons learned in mitigating temporary faults.

Key findings include:

  • The top three causes of temporary faults are wildlife, vegetation, and lightning.
  • Cover or guard over leads/bushings was found to be a very effective strategy.
  • Arresters are the best way to mitigate temporary faults caused by lightning.
  • Effective strategies for using TripSavers and Fusesavers.
  • Selective use of “fuse blow” and a “fuse save” schemes with reclosing devices.
  • Switching to a horizontal cross arm poles and increasing conductor spacing.
  • Use of vibration-resistant conductor to prevent galloping in high wind locations.
  • Use of relay data and fault current limiters to find temporary fault locations.

Table of Contents:


Who Should Use:

Distribution Planners, Standards Engineers, Power Quality and Reliability Engineers

This study was conducted in P16-3