scope:

Scope and field of application

Type of equipment

This standard applies to fusion welded wrought steel enclosures pressurized with dry air, inert gases, for example sulphur hexafluoride or nitrogen or a mixture of such gases, used in indoor or outdoor installations of high-voltage switchgear and controlgear with rated voltages 72,5 kV and above, where the gas is used principally for its dielectric andlor arc-quenching properties. 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

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

Production

The production of the enclosures shall be in accordance with documented welding procedures which shall be carried out by well trained and supervised welding personnel. Where international standards (ISO or CEN) are not available national standards may be used. NOTE. The standard will be revised as soon as possible when ISO or CEN standards covering the various aspects are available.

Quality assurance

It is the intention of this standard that the switchgear manufacturer shall be responsible for achieving and maintaining a consistent and adequate quality of product.

Sufficient examinations shall be made by the enclosure manufacturer to ensure that the materials, production and testing comply in all respects with the requirements of this standard and ISO 6213/1983. Inspection by user's inspectors shall not absolve the switchgear manufacturer from this responsibility to exercise such quality assurance procedures as to ensure that the requirements and intent of this standard are satisfied.

NOTE. Reference should be made to the ISO 9000 series of standards for quality systems.