UNE-EN IEC 60099-8-2018 PDF

Full title and description

STB UNE-EN IEC 60099-8:2018 — Surge arresters - Part 8: Metal-oxide surge arresters with external series gap (EGLA) for overhead transmission and distribution lines of a.c. systems above 1 kV. This is the Spanish adoption (UNE) of EN IEC 60099-8:2018, which implements the IEC 60099-8 technical content for national use.

Abstract

This part of IEC 60099 specifies requirements, tests and application guidance for metal-oxide surge arresters fitted with an external series gap (externally gapped line arresters — EGLA) used on overhead transmission and distribution lines solely to protect insulator assemblies from lightning-caused flashovers. It focuses on EGLA-specific design features and tests (for example repetitive charge-transfer rating Qrs, follow‑current interrupting, mechanical load and coordination tests) and explicitly excludes items not relevant for permanently connected surge arresters.

General information

• Status: Current / Active (national adoption of EN IEC 60099-8:2018).
• Publication date: 1 March 2018 (UNE adoption; base IEC publication date 14 November 2017).
• Publisher: Asociacion Espanola de Normalizacion (AENOR) / national standards body (UNE designation of the EN IEC text).
• ICS / categories: 29.240.10 (Substations. Surge arresters) and related codes (e.g., 29.120.50).
• Edition / version: EN IEC adoption 2018 (identical technical content to IEC 60099-8:2017, Edition 2.0).
• Number of pages: Typically published as ~77 pages in the UNE/EN edition (IEC master text listed with 67 pages depending on format).

Scope

Specifies requirements and tests for metal-oxide surge arresters with an external series gap (EGLA) intended for application on overhead transmission and distribution lines above 1 kV a.c., where their function is to protect insulator assemblies from lightning-caused flashovers. The standard sets out design definitions, type and routine tests and special verification tests for EGLA performance and coordination with insulators; it also lists items that are not covered because the EGLA concept differs from permanently connected arresters.

Key topics and requirements

• Definition and design requirements for externally gapped line arresters (EGLA).
• Tests specific to EGLAs: repetitive charge-transfer (Qrs) test for lightning discharges, follow-current interrupting test, mechanical load tests and coordination tests with insulator withstand levels.
• Requirements and methods for verification of the EGLA series gap behaviour and coordination with the metal‑oxide element.
• Exclusions and limits: switching impulse spark-over, long‑duration current duty, thermal stability and some ageing/by‑power‑frequency duties are not addressed for EGLA in this part.
• Normative references to related high‑voltage test standards used in test procedures (for example IEC 60060 series and other IEC 60099 parts).

Typical use and users

Used by transmission and distribution utilities, line designers, arrester manufacturers, test laboratories, certification bodies and asset managers for selection, testing, specification and installation guidance of EGLA devices intended to protect insulators against lightning flashover on overhead lines. It is also used by standards committees and technical authors preparing procurement and compliance documentation.

Related standards

Part of the IEC/EN 60099 series on surge arresters — closely related to IEC 60099-1, IEC 60099-4 (energy and charge-handling tests referenced in the EGLA Qrs test), and other parts of IEC 60099; normative cross-references include high‑voltage test standards such as IEC 60060-1 and IEC 60060-2. The UNE-EN IEC 60099-8:2018 text is the national adoption of EN IEC 60099-8:2018 and is technically identical to IEC 60099-8:2017; it replaced the previous 2011 edition.

Keywords

EGLA, externally gapped line arrester, metal-oxide surge arrester, MO arrester, surge arrester, overhead transmission, distribution lines, insulator protection, repetitive charge transfer (Qrs), lightning protection, follow‑current interrupting.

FAQ

Q: What is this standard?

A: A national (UNE) designation of EN IEC 60099-8:2018 that provides requirements and tests for metal-oxide surge arresters with an external series gap (EGLA) used to protect overhead-line insulator assemblies from lightning-caused flashovers.

Q: What does it cover?

A: Design definitions, type and verification tests (including Qrs, follow‑current interrupting and mechanical tests), coordination guidance with insulator withstand characteristics and EGLA-specific requirements; it excludes several aspects not applicable to the EGLA concept such as switching impulse spark‑over and long‑duration thermal duties.

Q: Who typically uses it?

A: Utilities, overhead-line designers, arrester manufacturers, testing and certification laboratories, procurement/specification engineers and standards committees involved in surge protection for overhead networks.

Q: Is it current or superseded?

A: The 2018 UNE/EN adoption implements the IEC 60099-8 second edition (IEC 60099-8:2017) and supersedes the previous 2011 edition; it is the current edition for the UNE/EN/IEC family as published.

Q: Is it part of a series?

A: Yes — it is one part of the IEC/EN 60099 series addressing surge arresters; other parts cover general requirements, metal-oxide arresters without external gaps, application guidance and related test methods.

Q: What are the key keywords?

A: EGLA, externally gapped line arrester, metal-oxide surge arrester, Qrs, insulator protection, lightning-caused flashover, surge protection, overhead lines.