Elbow and Overhead Arrester Design Evaluation
Overhead and elbow arresters are widely deployed on the distribution system to protect equipment and overhead lines from the damaging effects of lightning and switching surges. Modern distribution arresters are placed in polymer housings that have less field experience than the porcelain housed arresters. A very high percentage of porcelain housed arrester failures have been attributed to moisture ingression-related internal flashovers. Although many polymer-housed arresters have improved moisture-ingression performance due to the lack of free internal air space and improved sealing, many utilities continue to experience arrester failures. There are four major manufacturers of overhead and elbow arresters in the US: Elastimold, Joslyn, Cooper, and Hubbell. All four manufacturers have unique designs for assembling the metal oxide disks and sealing the insulation housing. The purpose of this DSTAR project is to evaluate and test the elecrical and mechanical design of a variety of overhead and elbow distribution arresters.