IEC TR 62039-2021 Selection guidelines for polymeric materials for outdoor use under HV stress.
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.
2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references， the latest edition of the referenced document (including any amendments) applies.
IEC 60243-1, Electric strength of insulating materials – Test methods – Part 1: Tests at power frequencies
IEC 60243-2, Electric strength of insulating materials – Test methods – Part 2: Additional requirements for tests using direct voltage
IEC 60455-2, Resin based reactive compounds used for electrical insulation – Part 2: Methods of test
IEC 60587，Electrical insulating materials used under severe ambient conditions – Test methods for evaluating resistance to tracking and erosion
IEC 60695-11-10, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and vertical flame test methods
IEC 61621，Dry, solid insulating materials – Resistance test to high-voltage, low-current arc discharges
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 hydrophobicity
surface of a solid insulating material characterized by its capacity to repel water or aqueous electrolyte solutions
Note 1 to entry: Hydrophobicity of a polymeric insulating material is, in general, a volume property by means of the chemical composition of a material at its surface.
Note 2 to entry: Nonetheless, hydrophobicity is strongly affected by surface effects such as:
• surface structure (i.e. roughness);
• chemical interaction between water and the solid surface (adsorption, absorption, swelling of the solid material in contact with water);
• an accumulated pollution layer.IEC TR 62039 pdf download.