PROTECTION OF A SURGE ARRESTER WITH A BETTER PROTECTION AGAINST FAILURE FROM THERMAL OVERLOAD IN CASE OF A TEMPORARY OVERVOLTAGE IN AN ELECTRICAL GRID LINE

摘要

This disclosure concerns a method for preventing an electrical grid from a failure in case of a temporary overvoltage. The method comprising the following steps:a) providing an electrical grid line (139), a surge arrester (140) and a disconnector device (10, 100) with a disconnector unit (25);b) connecting the surge arrester at one terminal to the electrical grid line (139);c) connecting the surge arrester at its other terminal to a second terminal of the disconnector device;d) connecting a first terminal (30) of the disconnector device to ground potential (37);e) interrupting the electrical connection in between the electrical grid line (139) and the ground potential (37) in case of a temporary overvoltage;f) protecting the surge arrester from failure due to a thermal overload caused by the temporary overvoltages by operating the disconnector device (10, 100) before the surge arrester fails due to a thermal overload of the surge arrester (140).