prEN 50XXX

Earthing systems of power installations with rated voltages above 1 kV

Scope

The standard deals with requirements for the erection of earthing systems of power installations with rated voltages above 1 kV and rated frequencies below 100 Hz. In details it contains: requirements for the dimensioning of earth electrodes and earthing conductors with respect to mechanical and thermal stability; limits for the touch voltage which have to be observed and measures to reduce touch voltages; specifications of the conductive parts which have to be earthed; criteria which must be fulfilled when connecting the low voltage system earth to the high-voltage system earth in high voltage substations; simple calculations and measuring methods to determine earthing resistances and related voltages; definitions of the terms used in the standard