Breaking Characteristics of 60 mm2 OPGW Strands due to DC Arc Simulating High-Energy Lightning Strike

Metal strands of composite fiber-optic ground wire (OPGW) are sometimes melted and broken by high-energy lightning strikes. Direct current (DC) arc tests simulating lightning strikes have thus been performed to obtain the melting and breaking characteristics of OPGW strands. In this paper, DC arc tests were conducted on the melting and breaking of 60 mm² OPGW for different currents and electric charges to clarify the characteristics of thin OPGWs. The results show that the number of broken strands increased as arc current decreased when comparing at the same electric charge, although it was previously reported that the melting quantity of the metal electrode due to arc discharges was proportional to electric charge without depending on the arc current. Furthermore, the characteristics of the tensile strength of the OPGW after DC arc tests were clarified.