Development of the dry-band arc on all-dielectric self-supporting cables during laboratory tests

Utilities frequently install All-Dielectric Self-Supporting (ADSS) fiber-optic cables on transmission lines. The cable jackets suffer damage due to dry-band arcing caused by high electric fields and pollution on the cable. A test method to determine cable resistance to dry-hand arcing is being considered for standardization by the IEEE. A new nozzle arrangement for the test is proposed in this paper. Using this nozzle the repeatability of the test is significantly improved over previous arrangements. Each test cycle consists of three stages: wetting, drying, and arcing. The three stages are examined in detail. Development of the dry-band arc on the cable jacket during the arcing period is presented. It is shown that the length of the are increases exponentially with time and reaches a stable length. The stable length is shown to be a function of the applied voltage. Index Terms--Arc discharges, optical fiber cables.