Application and settings inverse time relay characteristics for feeders overcurrent protection

The situation which can appear during switching on a long and loaded 10(20) kV distribution feeders are considered. The high inrush currents can cause unnecessary operation first or second stage of the overcurrent protection. The possibility of application time delay overcurrent characteristics of numerical protections are analysed. For characteristic distribution feeders 10(20) kV settings of overcurrent protections and other available options are checked by using simulation program as so as program for protective device coordination.