This Standard applies to cast aluminium alloy enclosures pressurized with dry air, inert gases, eg. sulphur hexafluoride, carbon tetrafluoride, or nitrogen or a mixture of such gases, used in indoor or outdoor installations of high-voltage switchgear and controlgear, where the gas is used principally for its di electric and/or arc-quenching properties, with rated voltages (1) 1 kV and up to and including 52 kV and with gas-filled compartments with design pressure greater than 3 bar (gauge); and (2) 72.5 kV and above.
The enclosures comprise parts of electrical equipment not necessarily limited to the following examples:
- Earthing switches
- Current transformers
- Voltage transformers
- Surge arresters
- Busbars and connections
The scope also covers pressurized components such as the center chamber of live tank switchgear, gas-insulated current transformers, etc.