Lightning–surge observation using optical fiber

Abstract

This paper describes lightning‐surge characteristics induced in different terminations of subscriber paired cable due to the same lightning discharge and its measurement method using optical fibers. Lightning‐surge‐inducing mechanisms in telecommunication lines have been developed from lightning‐surge data and calculated lightning‐surge values. From the results of study, it has been clarified that: (1) lightning surges in the telecommunication line are induced mainly from the horizontal component of electromagnetic fields based on the lightning discharge; (2) lightning‐surge voltage in underground cable is almost the same value as the surge in aerial cable; and (3) lightning‐surge voltage is reduced by the metalsheath shielding effect based on the metal sheath grounding.