scope:

This document presents the important material properties of polymeric materials used in outdoor insulation and, where applicable, lists standardized test methods including minimum requirements. If no standardized tests are available, the test methods reported in literature are summarized.

This document is valid for insulating materials having polymeric insulation, which are used in outdoor high voltage electrical applications with a system voltage greater than 1 000 V AC and 1 500 V DC (several tests are only defined for alternating current, which are not applicable for direct current). Such applications are relevant where the housing is an integral part of the device, for example in surge arresters and cable terminations. The scope of this document is limited to the insulation materials only and is not generally intended for coating materials (coating materials are, for example, thin layers applied on toughened glass and ceramic). Some tests mentioned in this document are applicable for coating and are under consideration by CIGRE. The performance of insulators in service depends on several factors such as the type of material, the design and environmental conditions. Consequently, the choice of materials that fulfil the requirements listed in Table 1 is a necessary condition but does not guarantee satisfactory performance when used in outdoor insulation.

In Annex A and Annex B different test methods for testing additional properties are given, which are not standardized.