BS EN 50069:2018

This document applies to welded composite enclosures of cast and wrought aluminium alloy pressurized with dry air, inert gases (e.g. sulphur hexafluoride or nitrogen or a mixture of such gases), used in indoor and outdoor installations of high-voltage switchgear and controlgear with rated voltages above 1kV, where the gas is used principally for its dielectric and/or arc-quenching properties with rated voltages:

• above 1kV and up to and including 52kV concerning gas-filled compartments with design pressure higher than 300kPa relative pressure (gauge);

• above 52kV concerning all gas-filled compartments.

The enclosures comprise parts of electrical equipment not necessarily limited to the following examples:

• circuit-breakers;

• switch-disconnectors;

• disconnectors;

• earthing switches;

• current transformers;

• voltage transformers;

• surge arrestors;

• busbars and connections;

• etc.

The scope also covers enclosures of pressurized components such as the centre chamber of live tank switchgear, gas-insulated current transformers, etc.