The technology of Live-Working was created by Dr. Béla Csikós around the year 1980. Subject specialists recognized the advantages of this technology, they started using it widely and at more and more voltage levels.
This technology demands safety measures, and attention on part of the workers, because of the fact that the cables are under voltage during the work procedure. One of the most important safety standards is the keeping of the required air distance from the part which is under voltage. From the different distances, in my thesis I introduce the calculation of minimum approach distance, which is based on standard EN_61472_Ed 3. The value of the above mentioned distance depends on many factors. Some of these factors change with the size of the transmission tower, and also with the length and material of the used insulator.
The aim of my thesis was to investigate the changing value of the minimum approach distance, if the newest silicon composite type of insulator are in use, or the traditional toughened glass. Calculations were made with three different types of transmission towers at 400 kV.