SIST EN 60099-8:2011

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 part of IEC 60099 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 standard defines surge arresters to protect the insulator assembly from lightning-caused overvoltages only. Therefore, and since the metal-oxide resistors are not permanently connected to the line, the following items are not considered for this standard:
• switching impulse sparkover 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 standard.

Überspannungsableiter - Teil 8: Metalloxid-Überspannungsableiter mit externer Serienfunkenstrecke (EGLA) für Übertragungs- und Verteilungsleitungen von Wechselstromsystemen über 1 kV

Parafoudres - Partie 8: Parafoudres à oxyde métallique avec éclateur extérieur en série (EGLA) pour lignes aériennes de transmission et de distribution de réseaux à courant alternatif de plus de 1 kV

La CEI 60099-8:2011 concerne les parafoudres à oxyde métallique, de ligne avec éclateur extérieur en série (EGLA) utilisés sur les lignes aériennes de transmission et de distribution, uniquement pour protéger les ensembles isolateurs contre les contournements provoqués par la foudre. Cette norme définit des parafoudres destinés à protéger l'ensemble isolateur uniquement contre les surtensions provoquées par la foudre. Les conceptions avec des EGLA à éclateur extérieur en série montés en parallèle sur un isolateur ne sont pas couvertes par la présente norme.

Prenapetostni odvodniki - 8. del: Kovinsko-oksidni prenapetostni odvodniki z zunanjim zaporedno vezanim iskriščem (EGLA) za nadzemne prenosne in razdelilne vode v izmeničnih sistemih nad 1 kV (IEC 60099-8:2011)

Ta del IEC 60099 zajema kovinsko-oksidne prenapetostne odvodnike z zunanjim zaporedno vezanim iskriščem (EGLA), ki se uporabljajo na nadzemnih prenosnih in razdelilnih vodih samo za zaščito izolacijskih sklopov pred prebojnim vžigom zaradi delovanja strele.
Ta standard določa prenapetostne odvodnike, ki ščitijo izolacijski sklop samo pred prenapetostjo, ki jo povzroča delovanje strele. Iz tega razloga in ker kovinsko-oksidni upori niso trajno povezani z vodom, ta standard ne obravnava naslednjih postavk:
• prebojne napetosti pri preklopnem impulzu;
• preostale napetosti pri strmem tokovnem impulzu in preklopnem tokovnem impulzu;
• toplotne stabilnosti;
• odpornosti proti dolgotrajnemu tokovnemu impulzu;
• električne napetosti v odvisnosti od časa trajanja prenapetostnega odvodnika;
• preskusa prekinjal;
• vpliva električne napetosti na delovanje pri staranju.
Glede na poseben koncept zasnove in posebno uporabo na nadzemnih prenosnih in razdelilnih vodih so vpeljane nekatere edinstvene zahteve in preskusi, kot so preskus preverjanja za koordinacijo med odpornostjo izolatorjev in zaščitno ravnjo EGLA, prekinjevalni preskus sledilnega toka, preskusi z mehansko obremenitvijo itd.
Ta standard ne zajema zasnov z zunanjim zaporedno vezanim iskriščem EGLA, nameščenim vzporedno z izolatorjem.

General Information

• Status: Withdrawn
• Publication Date: 11-May-2011
• Withdrawal Date: 09-Nov-2020
• ICS: 29.240.10 - Substations. Surge arresters
• Technical Committee: POD - Surge aresters
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 10-Nov-2020
• Due Date: 03-Dec-2020
• Completion Date: 10-Nov-2020
• Ref Project: EN 60099-8:2011 - 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

Relations

• Replaced By: SIST 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
• Effective Date: 01-May-2018
• Replaced By: SIST 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
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 60099-8:2011
01-junij-2011
3UHQDSHWRVWQLRGYRGQLNLGHO.RYLQVNRRNVLGQLSUHQDSHWRVWQLRGYRGQLNL]
]XQDQMLP]DSRUHGQRYH]DQLPLVNULãþHP(*/$]DQDG]HPQHSUHQRVQHLQ
UD]GHOLOQHYRGHYL]PHQLþQLKVLVWHPLKQDGN9,(&
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
Überspannungsableiter - Teil 8: Metalloxid-Überspannungsableiter mit externer
Serienfunkenstrecke (EGLA) für Übertragungs- und Verteilungsleitungen von
Wechselstromsystemen über 1 kV
Parafoudres - Partie 8: Parafoudres à oxyde métallique avec éclateur extérieur en série
(EGLA) pour lignes aériennes de transmission et de distribution de réseaux à courant
alternatif de plus de 1 kV
Ta slovenski standard je istoveten z: EN 60099-8:2011
ICS:
29.240.10 Transformatorske postaje. Substations. Surge arresters
Prenapetostni odvodniki
SIST EN 60099-8:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 60099-8:2011

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SIST EN 60099-8:2011

EUROPEAN STANDARD
EN 60099-8

NORME EUROPÉENNE
April 2011
EUROPÄISCHE NORM

ICS 29.240.10


English version


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
(IEC 60099-8:2011)


Parafoudres -  Überspannungsableiter – Teil 8:
Partie 8: Parafoudres à oxyde métallique Metalloxid-Überspannungsableiter mit
avec éclateur extérieur en série (EGLA) externer Serienfunkenstrecke (EGLA) für
pour lignes aériennes de transmission et Übertragungs- und Verteilungsleitungen
de distribution de réseaux à courant von Wechselstromsystemen über 1 kV
alternatif de plus de 1 kV (IEC 60099-8:2011)
(CEI 60099-8:2011)




This European Standard was approved by CENELEC on 2011-03-03. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels


© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60099-8:2011 E

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SIST EN 60099-8:2011
EN 60099-8:2011 - 2 -
Foreword
The text of document 37/370/FDIS, future edition 1 of IEC 60099-8, prepared by IEC TC 37, Surge
arresters, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as
EN 60099-8 on 2011-03-03.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2011-12-03
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2014-03-03
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60099-8:2011 was approved by CENELEC as a European
Standard without any modification.
__________

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SIST EN 60099-8:2011
- 3 - EN 60099-8:2011
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

1)
IEC 60060-1 1989 High-voltage test techniques - HD 588.1 S1 1991
Part 1: General definitions and test
requirements


2)
IEC 60060-2 1994 High-voltage test techniques - EN 60060-2 1994
Part 2: Measuring systems


IEC 60068-2-11 1981 Environmental testing - EN 60068-2-11 1999
Part 2-11: Tests - Test Ka: Salt mist


IEC 60068-2-14 2009 Environmental testing - EN 60068-2-14 2009
Part 2-14: Tests - Test N: Change of
temperature


IEC 60099-4 (mod) 2004 Surge arresters - EN 60099-4 2004
+ A1 2006 Part 4: Metal-oxide surge arresters without + A1 2006
+ A2 2009 gaps for a.c. systems + A2 2009


IEC 60270 2000 High-voltage test techniques - Partial EN 60270 2001
discharge measurements


IEC 60507 1991 Artificial pollution tests on high-voltage EN 60507 1993
insulators to be used on a.c. systems


IEC/TS 60815-1 2008 Selection and dimensioning of high-voltage - -
insulators intended for use in polluted
conditions -
Part 1: Definitions, information and general
principles


IEC 62217 2005 Polymeric insulators for indoor and outdoor EN 62217 2006
use with a nominal voltage > 1 000 V -
General definitions, test methods and
acceptance criteria


ISO 3274 - Geometrical Product Specifications (GPS) - EN ISO 3274 -
Surface texture: Profile method - Nominal
characteristics of contact (stylus) instruments


ISO 4287 - Geometrical Product Specifications (GPS) - EN ISO 4287 -
Surface texture: Profile method - Terms,
definitions and surface texture parameters



1)
HD 588.1 S1 is superseded by EN 60060-1:2010, which is based on IEC 60060-1:2010.
2)
EN 60060-2 is superseded by EN 60060-2:2011, which is based on IEC 60060-2:2010.

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SIST EN 60099-8:2011
EN 60099-8:2011 - 4 -
Publication Year Title EN/HD Year
ISO 4892-1 - Plastics - Methods of exposure to laboratory EN ISO 4892-1 -
light sources -
Part 1: General guidance


ISO 4892-2 - Plastics - Methods of exposure to laboratory EN ISO 4892-2 -
light sources -
Part 2: Xenon-arc lamps


ISO 4892-3 - Plastics - Methods of exposure to laboratory EN ISO 4892-3 -
light sources -
Part 3: Fluorescent UV lamps

---------------------- Page: 6 ----------------------

SIST EN 60099-8:2011

IEC 60099-8
®

Edition 1.0 2011-01

INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
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

Parafoudres –
Partie 8: Parafoudres à oxyde métallique avec éclateur extérieur en série (EGLA)
pour lignes aériennes de transmission et de distribution de réseaux à courant
alternatif de plus de 1 kV

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XB
ICS 29.240.10 ISBN 978-2-88912-312-4
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN 60099-8:2011
– 2 – 60099-8  IEC:2011
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Identification and classification . 11
4.1 EGLA identification . 11
4.2 EGLA classification . 12
5 Standard ratings and service conditions . 12
5.1 Standard rated voltages . 12
5.2 Standard rated frequencies . 13
5.3 Standard nominal discharge currents . 13
5.4 Service conditions . 13
5.4.1 Normal service conditions . 13
5.4.2 Abnormal service conditions . 13
6 Requirements . 13
6.1 Insulation withstand of the SVU and the complete EGLA . 13
6.1.1 Insulation withstand of the housing of the SVU . 13
6.1.2 Insulation withstand of EGLA with shorted (failed) SVU . 13
6.2 Residual voltages . 14
6.3 High current duty . 14
6.4 Lightning discharge capability . 14
6.5 Short-circuit performance of the SVU . 14
6.6 Mechanical performance . 14
6.7 Weather aging of SVU . 15
6.8 Reference voltage of the SVU . 15
6.9 Internal partial discharges . 15
6.10 Coordination between insulator withstand and EGLA protective level . 15
6.11 Follow current interrupting . 15
6.12 Electromagnetic compatibility . 15
6.13 End of life . 16
7 General testing procedure . 16
7.1 Measuring equipment and accuracy . 16
7.2 Test samples . 16
8 Type tests . 16
8.1 General . 16
8.2 Insulation withstand tests on the SVU housing and on the EGLA with failed
SVU . 17
8.2.1 General . 17
8.2.2 Insulation withstand test on the SVU housing . 17
8.2.3 Insulation withstand tests on EGLA with failed SVU . 18
8.3 Residual voltage tests . 19
8.3.1 General . 19
8.3.2 Procedure for correction and calculation of inductive voltages . 19
8.3.3 Lightning current impulse residual voltage test . 20

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SIST EN 60099-8:2011
60099-8  IEC:2011 – 3 –
8.3.4 High current impulse residual voltage test . 21
8.4 Standard lightning impulse sparkover test . 21
8.5 High current impulse withstand test . 22
8.5.1 Selection of test samples . 22
8.5.2 Test procedure . 22
8.5.3 Test evaluation . 22
8.6 Lightning discharge capability test . 23
8.6.1 Selection of test samples . 23
8.6.2 Test procedure . 23
8.6.3 Test parameters for the lightning impulse discharge capability test . 23
8.6.4 Measurements during the lightning impulse discharge capability test . 24
8.6.5 Rated lightning impulse discharge capability. 24
8.6.6 List of rated charge values . 24
8.7 Short-circuit tests . 24
8.7.1 General . 24
8.7.2 Preparation of the test samples . 25
8.7.3 Mounting of the test sample . 26
8.7.4 High-current short-circuit tests . 27
8.7.5 Low-current short-circuit test . 29
8.7.6 Evaluation of test results . 29
8.8 Follow current interrupting test . 34
8.8.1 General . 34
8.8.2 "Test method A" . 34
8.8.3 "Test method B" . 36
8.9 Mechanical load tests on the SVU . 38
8.9.1 Bending test . 38
8.9.2 Vibration test . 47
8.10 Weather aging tests . 48
8.10.1 General . 48
8.10.2 Sample preparation . 48
8.10.3 Test procedure . 48
8.10.4 Test evaluation . 48
8.10.5 Additional test procedure for polymer (composite and cast resin)
housed SVUs. 48
9 Routine tests . 49
9.1 General . 49
10 Acceptance tests . 50
10.1 General . 50
10.2 Reference voltage measurement of SVU . 50
10.3 Internal partial discharge test of SVU . 50
10.4 Radio interference voltage (RIV) test . 50
10.5 Test for coordination between insulator withstand and EGLA protective level . 51
10.5.1 General . 51
10.5.2 Front-of-wave impulse sparkover test . 51
10.5.3 Standard lightning impulse sparkover test . 51
10.6 Follow current interrupting test . 52
10.6.1 General . 52
10.6.2 Test procedure . 52
10.6.3 Test sequence . 52

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SIST EN 60099-8:2011
– 4 – 60099-8  IEC:2011
10.6.4 Test evaluation . 52
10.7 Vibration test on the SVU with attached electrode . 52
10.7.1 Test procedure and test condition . 53
10.7.2 Test evaluation . 53
Annex A (informative) Example of a test circuit for the follow current interrupting test . 54
Annex B (normative) Mechanical considerations . 55
Bibliography . 60

Figure 1 – Configuration of an EGLA with insulator and arcing horn . 7
Figure 2 – Examples of SVU units . 32
Figure 3 – Short-circuit test setup . 33
Figure 4 – Example of a test circuit for re-applying pre-failing circuit immediately
before applying the short-circuit test current . 34
Figure 5 – Thermo-mechanical test . 43
Figure 6 – Example of the test arrangement for the thermo-mechanical test and
direction of the cantilever load . 44
Figure 7 – Test sequence of the water immersion test . 45
Figure A.1 – Example of a test circuit for the follow current interrupting test . 54
Figure B.1 – Bending moment – Multi-unit SVU . 55
Figure B.2 – SVU unit . 57
Figure B.3 – SVU dimensions . 58

Table 1 – EGLA classification – “Series X” and “Series Y“ . 12
Table 2 – Steps of rated voltages (r.m.s. values) . 12
Table 3 – Type tests (all tests to be performed without insulator assembly) . 17
Table 4 – Test requirements . 30
Table 5 – Required currents for short-circuit tests . 31
Table 6 – Acceptance tests . 50
Table 7 – Virtual steepness of wave front of front-of-wave lightning impulses . 51

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SIST EN 60099-8:2011
60099-8  IEC:2011 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

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


FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60099-8 has been prepared by IEC technical committee 37: Surge
arresters.
The text of this standard is based on the following documents:
FDIS Report on voting
37/370/FDIS 37/377/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

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SIST EN 60099-8:2011
– 6 – 60099-8  IEC:2011
A list of all parts of IEC 60098 series, under the general title Surge arresters can be found on
the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.


IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

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SIST EN 60099-8:2011
60099-8  IEC:2011 – 7 –
INTRODUCTION
This part of IEC 60099 applies to the externally gapped line arrester (EGLA)
This type of surge arrester is connected directly in parallel with an insulator assembly. It
comprises a series varistor unit (SVU), made up from non-linear metal-oxide resistors
encapsulated in a polymer or porcelain housing, and an external series gap, see Figure 1.
The purpose of an EGLA is to protect the parallel-connected insulator assembly from
lightning-caused overvoltages. The external series gap, therefore, should spark over only due
to fast-front overvoltages. The gap should withstand all power-frequency and slow-front
overvoltages occurring on the system.
In the event of SVU failure, the external series gap should be able to isolate the SVU from the
system.


EGLA
Tower arm
Insulator assembly
S
(insulator assembly,
Series varistor unit V
with/without arcing horns
U or grading elements)

External series gap
(without an insulator
Conductor
in parallel)
IEC  2896/10



Figure 1 – Configuration of an EGLA with insulator and arcing horn

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SIST EN 60099-8:2011
– 8 – 60099-8  IEC:2011
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



1 Scope
This part of IEC 60099 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 standard defines surge arresters to protect the insulator assembly from lightning-caused
overvoltages only. Therefore, and since the metal-oxide resistors are not permanently
connected to the line, the following items are not considered for this standard:
• switching impulse sparkover 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 o
...