Determining currents of cable sheaths by means of current load factor and current reduction factor

A new method for determining sheath currents as the consequence of electromagnetic coupling during line-to-ground short circuit is described in this article. This method is based on using both the current load factor and the current reduction factor. The model cables are selected to represent major constructions encountered in practice. The cable line consists of three single-core cables laid in trefoil formation and touching each other. Cable sheaths are grounded at both ends. Current load factor and current reduction factor are characteristic data of the analyzed cable line. The method presented in this paper is easy to use.