Live re-stringing of 138 kV lines

This paper reports on research to develop new safe procedures for re-stringing an energized double-circuit 138 kV transmission line. The re-stringing operation requires the installation of a large stringing block and the removal, when necessary, of two insulator units from the string. This alters the worksite withstand characteristics significantly and lowers its insulation level. However, tests have shown that live working procedures could be developed for such a task, provided appropriate precautions are taken.