IEC 62217 ED3

Polymeric HV insulators for indoor and outdoor use - General definitions, test methods and acceptance criteria

Scope

IEC 62217:2025 is applicable to polymeric insulators for AC systems with a nominal voltage greater than 1 000 V (frequency less than 100 Hz) and DC systems with a nominal voltage greater than 1 500 V whose insulating body consists of one or various organic materials. Polymeric insulators covered by this document are intended for use both on HV overhead lines and in substations, in both indoor and outdoor applications. They include composite insulators with solid and hollow core and resin insulators. Hybrid insulators with ceramic core and polymeric housing are also included, while coated insulators (e.g. with RTV silicone rubber coatings) are not included in this standard. Electrical tests described in this document are done under AC voltage and are in general applicable to insulators to be used in DC systems too. Tests under DC voltage are intended to reflect up-to-date knowledge and experience.

Only polymeric housing materials of hybrid insulators are specified in this document. Tests for core materials and the interfaces between housing and core of hybrid insulators are not included.

The object of this document is
- to define the common terms used for polymeric insulators;
- to prescribe common test methods for design tests on polymeric insulators;
- to prescribe acceptance or failure criteria, if applicable;

These tests, criteria and recommendations are intended to ensure a satisfactory lifetime under normal operating and environmental conditions. This document includes design tests intended to reject materials or designs which are inadequate under normal operating and environmental conditions. This document defines test methods and acceptance criteria. The applicable tests are given in the relevant product standard.

This third edition cancels and replaces the second edition published in 2012. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) The scope of the document is specified to comprise composite insulators with solid and hollow core and resin insulators used for both AC and DC systems in indoor and outdoor applications of HV overhead lines and substations; hybrid insulators (defined in IEC TS 62896) with ceramic core and polymeric housing are also included, while coated insulators (e.g. with Room Temperature Vulcanized (RTV) silicone rubber coatings) are not considered in this document;
b) Steep-front impulse voltage test is modified to avoid unwanted flashovers between the leads of the electrodes;
c) Differences between hydrophobicity transfer material (HTM) and non-HTM housing materials are specified and relevant test methods and acceptance criteria for polymeric insulators with HTM housing are introduced;
d) The previous water diffusion test on core materials with or without housing is split into two tests. One is on core materials without housing, the other is on core materials with housing. The acceptance criteria are modified;
e) Stress corrosion test for core materials is introduced;
f) Annex B summarizes the test application for evaluating the quality of interfaces and connections of end fittings, housing materials and core materials;
g) Annex E is introduced to emphasize the need for control of electric fields of polymeric insulators for AC. The control of electric fields of polymeric insulators for DC is still under consideration.