INTERNAL ARC: PEOPLE SAFETY IN THE ELECTRICAL WIRING

Abstract

The aim of this article is to describe the internal arc phenomenon, - an extremely fast, almost explosive and unattended process of transformation from an initial electric power to the generation of a pressure and heat wave inside the medium it’s produced- its consequences for safety, current methods of limiting them and current regulations in general for equipment used in medium-voltage electrical distribution networks. Taking into account that this type of equipment is found throughout the distribution network in both public buildings and unrestricted access areas, safety (of operators and the general public) must be taken into account in the design of equipment and installations to minimize the risk of internal arcs occurring. This is the gist of, for example, ITC16 of the Spanish Regulation on Power Plants and transformer substations. In addition to the construction aspects specific to each device in which the manufacturer has to take steps to minimize the risks of an internal arc occurring, it is understood to be vitally important that users, installers and designers of Medium Voltage installations are familiar with the installation conditions stated by the manufacturer and thus avoid risks.