Earth System and Improvement plan for Shield of Cable with Separable Connector

Separable connector is used for connecting a cable to a switch gear in new energy generation sites because of its compact size. One of terminations of cable shield is not sometimes earthed in order to reduce power loss due to shield current. A part of the separable connector made up of semi- conducting material is connected to an earthing system. Furthermore, the end of the shield layers of the cable contacts with semiconducting material of separable connector. The shield layer of a cable might be regarded to be connected to the earthing system through resistance. Hence, the authors carried out impulse tests for separable connector with cable. This paper presents some remarkable results. Lightning overvoltage causes a serious damage in the semiconducting layer of separable connector when one of the terminations of the cable shield is not earthed. An effective method not to cause a damage in the semiconducting layer of the separable connector is the use of a surge protective device between the earth terminal of a separable connector and cable shield.