IEC 61643-331:2020
(Main)Components for low-voltage surge protection - Part 331: Performance requirements and test methods for metal oxide varistors (MOV)
Components for low-voltage surge protection - Part 331: Performance requirements and test methods for metal oxide varistors (MOV)
IEC 61643-331:2020 is available as IEC 61643-331:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 61643-331:2020 is a test specification for metal oxide varistors (MOV), which are used for applications up to 1 000 V AC or 1 500 V DC in power lines, or telecommunication, or signalling circuits. They are designed to protect apparatus or personnel, or both, from high transient voltages. This document applies to MOVs having two electrodes and hybrid surge protection components. This document also does not apply to mountings and their effect on the MOV’s characteristics. Characteristics given apply solely to the MOV mounted only in the ways described for the tests. This third edition cancels and replaces the second edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- a Varistor MCOV rating assurance test;
- an energy rating test (2ms);
- revised Dielectric strength and insulation resistance tests.
Composants pour parafoudres basse tension - Partie 331: Exigences de performance et méthodes d'essai pour les varistances à oxyde métallique (MOV)
IEC 61643-331:2020 est disponible sous forme de IEC 61643-331:2020 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
IEC 61643-331:2020 est une spécification d'essai pour les varistances à oxyde métallique (MOV, Metal Oxide Varistor) utilisées dans des applications jusqu'à 1 000 V en courant alternatif ou 1 500 V en courant continu sur les lignes électriques ou de télécommunication, ou dans les circuits de signalisation. Elles sont conçues pour protéger l'appareillage et/ou le personnel contre les hautes tensions transitoires. Le présent document s'applique aux MOV comportant deux électrodes et des composants pour parafoudres hybrides. Le présent document ne s'applique pas aux montages et à leurs effets sur les caractéristiques des MOV. Les caractéristiques indiquées s'appliquent exclusivement aux MOV montées uniquement dans le sens décrit pour les essais. Cette troisième édition annule et remplace la deuxième édition parue en 2017. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- un essai d'assurance des caractéristiques MCOV assignées de la varistance a été ajouté;
- un essai des caractéristiques assignées d'énergie (2 ms) a été ajouté;
- les essais de rigidité diélectrique et de résistance d'isolement ont été revus.
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IEC 61643-331 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
colour
inside
Components for low-voltage surge protection –
Part 331: Performance requirements and test methods for metal oxide varistors
(MOV)
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
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variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary
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publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or need CISPR.
further assistance, please contact the Customer Service
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IEC 61643-331 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
colour
inside
Components for low-voltage surge protection –
Part 331: Performance requirements and test methods for metal oxide varistors
(MOV)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.040.20 ISBN 978-2-8322-7905-2
– 2 – IEC 61643-331:2020 © IEC 2020
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, symbols and abbreviated terms . 8
3.1 Terms and definitions . 8
3.1.1 Ratings . 8
3.1.2 Characteristics. 9
3.2 Symbols and abbreviated terms used in this document . 11
3.2.1 Symbols . 11
3.2.2 Abbreviated terms . 11
4 Service conditions . 12
4.1 Operating and storage temperature ranges . 12
4.2 Altitude or atmospheric pressure range . 12
4.3 Relative Humidity . 12
5 Mechanical requirements and materials . 12
5.1 Robustness of terminations . 12
5.2 Solderability . 12
5.3 Marking . 12
6 General . 13
6.1 Failure rates . 13
6.2 Test standard atmospheric conditions . 13
7 Electrical requirements . 13
7.1 Varistor voltage (V ) . 13
V
7.2 Maximum AC (DC) continuous voltage (V / V ) . 13
M(AC) M(DC)
7.3 Standby current (I ) . 13
D
7.4 Capacitance (C ) . 13
V
7.5 Clamping voltage (V ) . 13
C
7.6 Electrostatic discharge (ESD) (for SMD type MOV only). 15
7.7 Rated impulse energy . 15
7.8 Nominal discharge current (I ) . 15
n
7.9 Endurance . 15
7.10 Limited current temporary overvoltage . 15
8 Standard design test criteria . 16
8.1 General . 16
8.2 Ratings . 16
8.2.1 Single-impulse maximum current (I ) . 16
TM
8.2.2 Next impulse . 16
8.2.3 Maximum Continuous voltage (V ) . 17
M
8.3 Electrical Characteristics . 17
8.3.1 Clamping voltage (V ) . 17
C
8.3.2 Standby current (I ) . 17
D
8.3.3 Varistor voltage (V ) . 17
V
8.3.4 Capacitance (C ) . 18
V
8.3.5 Rated energy . 18
8.4 Varistor Rating Assurance Testing . 18
8.5 ESD test . 19
9 Nominal discharge current and limited current temporary overvoltage. 19
9.1 Thermally protected varistors – Sequence of tests . 19
9.2 Temperature and humidity cycle conditioning . 19
9.3 Nominal discharge current (I ) test description . 20
n
9.3.1 General . 20
9.3.2 Pass/fail criteria . 22
9.4 Limited current temporary overvoltage test description and procedure for
thermally protected varistors . 22
9.4.1 General . 22
9.4.2 Sample preparation . 23
9.4.3 Test conditions . 23
9.4.4 Pass/fail criteria . 23
9.5 Dielectric testing . 24
9.5.1 Test conditions for thermally protected MOV . 24
9.5.2 Setup from foil to leads . 25
9.5.3 Pass criteria . 25
9.6 Insulation Resistance . 25
Annex A (informative) MOV testing according to the IEC 61643-11:2011 Surge
protective devices for the Class I, II and III . 26
A.1 General . 26
A.2 MOV selection . 26
A.3 Cross reference list of abbreviations, descriptions and definitions . 26
A.4 Operating duty test . 27
A.4.1 General . 27
A.4.2 Class I and II operating duty tests (8.4.4.3) . 32
A.4.3 Additional duty test for test class I . 33
A.4.4 Class III operating duty tests . 33
A.4.5 Pass criteria for all operating duty tests and for the additional duty test
for test class I . 34
A.4.6 Preferred parameters of impulse discharge current I used for Class I
imp
additional duty tests . 34
A.4.7 Preferred values of impulse discharge current I used for Class I and
n
Class II residual voltage and operating duty tests . 35
A.4.8 Preferred values of combination generator waveshape used for Class III
tests . 35
Annex B (informative) IEC 61051 Varistors for use in electronic equipment . 38
Annex C (normative) Accelerated Endurance screening test . 39
C.1 Accelerated endurance screening test . 39
C.2 Preparation of sample . 39
C.3 Test conditions . 39
C.4 Refer to test circuit diagram as shown in Figure C.1. . 39
C.5 Pass criteria . 40
Annex D (informative) Proposed test method of MTTF – Mean time to failure (MTTF) . 41
D.1 Sampling plans . 41
D.2 Total test hours . 41
D.3 Samples. 41
D.4 Test set-up . 42
D.5 Intermediate measurements . 42
D.6 Failure criteria . 42
– 4 – IEC 61643-331:2020 © IEC 2020
D.7 Acceptance criteria . 42
Figure 1 – V-I characteristic of an MOV .
...
IEC 61643-331 ®
Edition 3.0 2020-03
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Components for low-voltage surge protective devices protection –
Part 331: Performance requirements and test methods for metal oxide varistors
(MOV)
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.
IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
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once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.
need further assistance, please contact the Customer Service
Centre: sales@iec.ch.
IEC 61643-331 ®
Edition 3.0 2020-03
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Components for low-voltage surge protective devices protection –
Part 331: Performance requirements and test methods for metal oxide varistors
(MOV)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.040.20 ISBN 978-2-8322-8023-2
– 2 – IEC 61643-331:2020 RLV © IEC 2020
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, symbols and abbreviated terms . 8
3.1 Terms and definitions . 8
3.1.1 Ratings . 8
3.1.2 Characteristics. 9
3.2 Symbols and abbreviated terms used in this document . 11
3.2.1 Symbols . 11
3.2.2 Abbreviated terms . 11
4 Service conditions . 12
4.1 Operating and storage temperature ranges . 12
4.2 Altitude or atmospheric pressure range . 12
4.3 Relative Humidity . 12
5 Mechanical requirements and materials . 12
5.1 Robustness of terminations . 12
5.2 Solderability . 12
5.3 Marking . 12
6 General . 13
6.1 Failure rates . 13
6.2 Test standard atmospheric conditions . 13
7 Electrical requirements . 13
7.1 Nominal Varistor voltage (V ) . 13
V
7.2 Maximum AC (DC) continuous operating voltage (V / V ) . 13
M(AC) M(DC)
7.3 Standby current I (I ) . 13
DC
D
7.4 Capacitance (C ) . 13
V
7.5 Clamping voltage (V ) . 13
C
7.6 Electrostatic discharge (ESD) (for SMD type MOV only). 15
7.7 Rated impulse energy (W ) . 15
TM
7.8 Nominal discharge current (I ) . 15
n
7.9 Endurance . 15
7.10 Limited current temporary overvoltage . 16
8 Standard design test criteria . 16
8.1 General . 16
8.2 Ratings . 16
8.2.1 Single-impulse maximum current (I ) . 16
TM
8.2.2 Next impulse . 17
8.2.3 Maximum Continuous rated voltage (V ) . 17
M
8.3 Electrical Characteristics . 17
8.3.1 Clamping voltage (V ) . 17
C
8.3.2 Standby current (I ) . 17
D
8.3.3 Nominal Varistor voltage (V ) (V ) . 18
N V
8.3.4 Capacitance (C ) . 18
V
8.3.5 Rated energy . 18
8.4 Endurance Varistor Rating Assurance Testing . 18
8.5 ESD test Method . 19
9 Nominal discharge current and limited current temporary overvoltage. 19
9.1 Thermally protected varistors – Sequence of tests . 19
9.2 Temperature and humidity cycle conditioning . 20
9.3 Nominal discharge current I(n) (I ) test description . 20
n
9.3.1 General . 20
9.3.2 Pass/fail criteria . 22
9.4 Limited current temporary overvoltage test description and procedure for
thermally protected varistors . 22
9.4.1 General . 22
9.4.2 Sample preparation . 23
9.4.3 Test conditions . 23
9.4.4 Pass/fail criteria . 23
9.5 Dielectric testing . 24
9.5.1 Test conditions for thermally protected MOV . 24
9.5.2 Setup from foil to leads . 25
9.5.3 Pass criteria . 25
9.6 Insulation Resistance . 25
Annex A (informative) MOV testing according to the IEC 61643-11:2011 Surge
protective devices for the Class I, II and III . 26
A.1 General . 26
A.2 MOV selection . 26
A.3 Cross reference list of abbreviations, descriptions and definitions . 26
A.4 Operating duty test . 27
A.4.1 General . 27
A.4.2 Class I and II operating duty tests (8.3.4.3) . 32
A.4.3 Additional duty test for test class I . 33
A.4.4 Class III operating duty tests . 33
A.4.5 Pass criteria for all operating duty tests and for the additional duty test
for test class I . 34
A.4.6 Preferred parameters of impulse discharge current I used for Class I
imp
additional duty tests . 34
A.4.7 Preferred values of impulse discharge current I used for Class I and
n
Class II residual voltage and operating duty tests . 35
A.4.8 Preferred values of combination generator waveshape used for Class III
tests . 36
Annex B (informative) IEC 61051 Varistors for use in electronic equipment . 38
Annex C (informative normative) Accelerated Endurance screening test . 39
C.1 Accelerated endurance screening test . 39
C.2 Preparation of sample . 39
C.3 Test conditions . 39
C.4 Refer to test circuit diagram as shown in Figure C.1. . 39
C.5 Pass criteria . 40
Annex D (informative) Proposed test method for determination of MTTF – Mean time
to failure (MTTF) . 41
D.1 Sampling plans . 41
D.2 Total test hours . 41
D.3 Samples. 41
D.4 Test set-up . 42
D.5 Intermediate measurements . 42
– 4 – IEC 61643-331:2020 RLV © IEC 2020
D.6 Failure criteria . 42
D.
...
IEC 61643-331 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Components for low-voltage surge protection –
Part 331: Performance requirements and test methods for metal oxide varistors
(MOV)
Composants pour parafoudres basse tension –
Partie 331: Exigences de performance et méthodes d'essai pour les varistances
à oxyde métallique (MOV)
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and once 67 000 electrotechnical terminology entries in English and
a month by email. French extracted from the Terms and Definitions clause of IEC
publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or need CISPR.
further assistance, please contact the Customer Service
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IEC 61643-331 ®
Edition 3.0 2020-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Components for low-voltage surge protection –
Part 331: Performance requirements and test methods for metal oxide varistors
(MOV)
Composants pour parafoudres basse tension –
Partie 331: Exigences de performance et méthodes d'essai pour les varistances
à oxyde métallique (MOV)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.040.20 ISBN 978-2-8322-8558-9
– 2 – IEC 61643-331:2020 © IEC 2020
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, symbols and abbreviated terms . 8
3.1 Terms and definitions . 8
3.1.1 Ratings . 8
3.1.2 Characteristics. 9
3.2 Symbols and abbreviated terms used in this document . 11
3.2.1 Symbols . 11
3.2.2 Abbreviated terms . 11
4 Service conditions . 12
4.1 Operating and storage temperature ranges . 12
4.2 Altitude or atmospheric pressure range . 12
4.3 Relative Humidity . 12
5 Mechanical requirements and materials . 12
5.1 Robustness of terminations . 12
5.2 Solderability . 12
5.3 Marking . 12
6 General . 13
6.1 Failure rates . 13
6.2 Test standard atmospheric conditions . 13
7 Electrical requirements . 13
7.1 Varistor voltage (V ) . 13
V
7.2 Maximum AC (DC) continuous voltage (V / V ) . 13
M(AC) M(DC)
7.3 Standby current (I ) . 13
D
7.4 Capacitance (C ) . 13
V
7.5 Clamping voltage (V ) . 13
C
7.6 Electrostatic discharge (ESD) (for SMD type MOV only). 15
7.7 Rated impulse energy . 15
7.8 Nominal discharge current (I ) . 15
n
7.9 Endurance . 15
7.10 Limited current temporary overvoltage . 15
8 Standard design test criteria . 16
8.1 General . 16
8.2 Ratings . 16
8.2.1 Single-impulse maximum current (I ) . 16
TM
8.2.2 Next impulse . 16
8.2.3 Maximum Continuous voltage (V ) . 17
M
8.3 Electrical Characteristics . 17
8.3.1 Clamping voltage (V ) . 17
C
8.3.2 Standby current (I ) . 17
D
8.3.3 Varistor voltage (V ) . 17
V
8.3.4 Capacitance (C ) . 18
V
8.3.5 Rated energy . 18
8.4 Varistor Rating Assurance Testing . 18
8.5 ESD test . 19
9 Nominal discharge current and limited current temporary overvoltage. 19
9.1 Thermally protected varistors – Sequence of tests . 19
9.2 Temperature and humidity cycle conditioning . 19
9.3 Nominal discharge current (I ) test description . 20
n
9.3.1 General . 20
9.3.2 Pass/fail criteria . 22
9.4 Limited current temporary overvoltage test description and procedure for
thermally protected varistors . 22
9.4.1 General . 22
9.4.2 Sample preparation . 23
9.4.3 Test conditions . 23
9.4.4 Pass/fail criteria . 23
9.5 Dielectric testing . 24
9.5.1 Test conditions for thermally protected MOV . 24
9.5.2 Setup from foil to leads . 25
9.5.3 Pass criteria . 25
9.6 Insulation Resistance . 25
Annex A (informative) MOV testing according to the IEC 61643-11:2011 Surge
protective devices for the Class I, II and III . 26
A.1 General . 26
A.2 MOV selection . 26
A.3 Cross reference list of abbreviations, descriptions and definitions . 26
A.4 Operating duty test . 27
A.4.1 General . 27
A.4.2 Class I and II operating duty tests (8.4.4.3) . 32
A.4.3 Additional dut
...
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