Applies to ceramics and glass hollow insulators intended for general use in electrical equipment and ceramic hollow insulators intended for use with a permanent gas pressure in switchgear and controlgear.

1.1 General This standard is applicable to ceramic and glass hollow insulators intended for general use in electrical equipment; ceramic hollow insulators intended for use with a permanent gas pressure in switchgear and controlgear. These insulators are intended for indoor and outdoor use in electrical equipment, operating on alternating current with a rated voltage greater than 1 000 V and a frequency not greater than 100 Hz or for use in direct-current equipment with a rated voltage of greater than 1 500 V. The hollow insulators are intended for use in electrical equipment, for example: circuit-breakers, switch-disconnectors, disconnectors, earthing switches, instrument transformers, surge arresters, bushings, cable sealing ends, capacitors. It is not the object of this standard to prescribe dielectric type tests because the withstand voltages are not characteristics of the hollow insulator itself but of the apparatus of which it ultimately forms a part. 1.2 Hollow insulators or hollow insulator bodies intended for general use Hollow insulators or insulator bodies of ceramic material or glass, intended for use without pressure; with permanent pressure ≤50 kPa gauge; with permanent gas pressure >50 kPa gauge in combination with an internal volume < 1 l (1 000 cm3); with permanent hydraulic pressure. The object of this standard is to define the terms used; the mechanical and dimensional characteristics of hollow insulators and hollow insulator bodies; the electrical soundness of the wall; the conditions under which the specified values of these characteristics are verified; the methods of test; the acceptance criteria. 1.3 Ceramic hollow insulators intended for use with permanent gas pressure Hollow insulators or hollow insulator bodies with their fixing devices, intended for use with permanent gas pressure: permanent gas pressure >50 kPa gauge in combination with an internal volume ≥1 l (1 000 cm3). NOTE 1 The gas can be dry air, inert gases, for example, SF6 or nitrogen or a mixture of such gases. The object of this standard is to define the terms used; the mechanical and dimensional characteristics of hollow insulators and hollow insulator bodies; the electrical soundness of the wall; the conditions under which the specified values of these characteristics are verified; the methods of test; the acceptance criteria; design rules; test procedures and test values. NOTE 2 Hollow insulators or hollow insulator bodies are usually integrated into electrical equipment which is electrically type tested as required by the equipment standard.