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.