Dimensioning of SPD for the protection against surges due to lightning to LV overhead lines

The papers deals with the selection of SPD for protection of apparatus within a structure against lightning surges from the connected LV power supply lines. The basic arrangement includes an aerial ten poles low voltage line closed on one side by HV/LV transformer and on other side by apparatus to be protected. By several computer simulations information have been obtained for the selection of SPD to be installed at the entry point of the line into the structure and discussed on the light of international standard.