电涌放电器第8部分:1kV以上交流系统架空输配电线路用带外部串联间隙（EGLA）的金属氧化物电涌放电器

[中文适用范围]： 本部分IEC 60099涵盖了用于架空输电和配电线路的外部串联间隙金属氧化物避雷器（外部间隙线路避雷器（EGLA）），仅用于保护绝缘子组件免受雷电引起的闪络。 本文档定义了仅用于保护绝缘子组件免受雷电引起的过电压的避雷器。因此，由于金属氧化物电阻器不永久连接到线路，本文档不考虑以下项目： - 开关冲击火花放电电压； - 陡坡电流和开关电流冲击下的残余电压； - 热稳定性； - 长时间电流冲击耐受能力； - 避雷器的工频电压与时间特性； - 断开器测试； - 工频电压老化测试。 考虑到特殊的设计概念和在架空输电和配电线路上的特殊应用，引入了一些独特的要求和测试，例如绝缘子耐受与EGLA保护水平之间的协调验证测试、跟随电流中断测试、机械负载测试等。 本文档不包括与绝缘子并联安装的EGLA外部串联间隙的设计。 [外文原描述]： IEC 60099-8:2017 RLV contains both the official IEC International Standard and its Redline version. The Redline version is available in English only and provides you with a quick and easy way to compare all the changes between the official IEC Standard and its previous edition. IEC 60099-8:2017 covers metal-oxide surge arresters with external series gap (externally gapped line arresters (EGLA)) that are applied on overhead transmission and distribution lines, only to protect insulator assemblies from lightning-caused flashovers. This document defines surge arresters to protect the insulator assembly from lightning-caused over-voltages only. Therefore, and since metal-oxide resistors are not permanently connected to the line, the following items are not considered for this document: - switching impulse spark-over voltage; - residual voltage at steep current and switching current impulse; - thermal stability; - long-duration current impulse withstand duty; - power-frequency voltage versus time characteristics of an arrester; - disconnector test; - aging duties by power-frequency voltage. Considering the particular design concept and the special application on overhead transmission and distribution lines, some unique requirements and tests are introduced, such as the verification test for coordination between insulator withstand and EGLA protective level, the follow current interrupting test, mechanical load tests, etc. Designs with the EGLA's external series gap installed in parallel to an insulator are not covered by this document. This second edition cancels and replaces the first edition published in 2011. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: The Lightning discharge capability test has been completely re-written and re-named to Test to verify the repetitive charge transfer rating, Qrs with lightning discharges to reflect changes introduced in IEC 60099-4 Ed.3 (2014) regarding new methods for rating the energy and charge handling capability of metal-oxide arresters. In addition to testing to evaluate the performance of the MO resistors, procedures for evaluating the performance of the EGLA series gaps have been introduced. - Omissions from Ed. 1 of this standard have been included, notably an RIV test and a means for determining the thermal time constant of the SUV portion of the EGLA. - Definitions for new terms have been added - A number of NOTES in Ed. 1 have been converted to normative requirements Keywords: externally gapped line arresters (EGLA), lightning-caused over-voltages