Abstract :
IEC840 was written by IEC Study Committee 20A Working Group 11, based on a recommendation produced by CIGRE SC 21 WG9. The recommendation was the result of international collaboration and agreement and based on surveys of practice in Europe and Japan, supplemented by research and development data provided by the participants. Not all the recommendations were taken on board as IEC´s goal is a standard having worldwide acceptance and not just reflecting requirements of utilities in Europe. CENELEC TC20 WG9 has had the task of collating national requirements for a set of compendium approach Harmonised Documents (HDs) for LV and MV cables. The accompanying HDs for accessories on the other hand reflect a rationalisation approach. When it came to writing the HV polymeric cables HD632, the WG decided that this should be achieved in a similar manner, by using IEC840 as a base with a minimum input in the form of additional national requirements. The outcome was unexpected with some 500 pages of text offered as additional national data. This paper examines some additions that are being discussed in international fora and may find their way into HD632 and also those changes to IEC840 that could eventually also form part of HD632. IEC840 covers tests for system voltages higher than 30 kV and up to 150 kV and there are plans to extend this to 500 kV. HD632 covers the same voltage range
