IEC 61051-1:2007

Varistors for use in electronic equipment - Part 1: Generic specification

IEC 61051-1:2007 is applicable to varistors with symmetrical voltage current characteristics for use in electronic equipment. This second edition cancels and replaces the first edition published in 1991 and constitutes a minor revision related to tables, figures and references.

Varistances utilisées dans les équipements électroniques - Partie 1: Spécification générique

La CEI 61051-1:2007 est applicable aux varistances à caractéristique tension-courant symétrique utilisées dans les équipements électroniques. Cette deuxième édition annule et remplace la première édition publiée en 1991 et constitue une révision mineure qui porte sur des tableaux, des figures et des références.

General Information

• Status: Published
• Publication Date: 10-Apr-2007
• ICS: 31.040.99 - Other resistors
• Technical Committee: TC 40 - Capacitors and resistors for electronic equipment
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 29-Oct-2018

Relations

• Revised: IEC 61051-1:2018 - Varistors for use in electronic equipment - Part 1: Generic specification
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 61051-1
QC 420000
Second edition
2007-04
Varistors for use in electronic equipment –
Part 1:
Generic specification
Reference number
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
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please contact the address below or your local IEC member National Committee for further information.

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About the IEC
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International Standards for all electrical, electronic and related technologies.

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INTERNATIONAL IEC
STANDARD 61051-1
QC 420000
Second edition
2007-04
Varistors for use in electronic equipment –
Part 1:
Generic specification
PRICE CODE
Commission Electrotechnique Internationale V
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 61051-1 © IEC:2007(E)
CONTENTS
FOREWORD.5

1 General .7

1.1 Scope.7

1.2 Object .7

1.3 Normative references .7

2 Technical data.8

2.1 Units, symbols and terminology .8
2.2 Terms and definitions .9
2.3 Preferred values and characteristics.13
2.4 Marking .13
2.4.1 General .13
2.4.2 Coding.14
3 Quality assessment procedures.14
3.1 Qualification approval/quality assessment systems .14
3.2 Primary stage of manufacture.14
3.3 Structurally similar components.14
3.4 Qualification approval procedures .15
3.5 Quality conformance inspection.15
3.5.1 Certified records of released lots .15
3.5.2 Delayed delivery.15
3.5.3 Release for delivery before the completion of Group B tests .16
3.6 Alternative test methods .16
3.7 Unchecked parameters.16
4 Test and measurement procedures.16
4.1 General .16
4.2 Standard atmospheric conditions.16
4.2.1 Standard atmospheric conditions for testing .16
4.2.2 Recovery conditions .17
4.2.3 Referee conditions .17
4.2.4 Reference conditions.17
4.3 Drying and recovery .17
4.4 Visual examination and check of dimensions.18

4.4.1 Visual examination .18
4.4.2 Marking .18
4.4.3 Dimensions (gauging).18
4.4.4 Dimensions (detail).18
4.5 Nominal varistor voltage or leakage current (not applicable to pulse
measurements) .
4.5.1 Test procedure .18
4.5.2 Measurement and requirements.18
4.6 Pulse current.18
4.6.1 Standard pulse currents.19
4.6.2 Tolerances .19
4.6.3 Measurement of the pulse current .19
4.7 Voltage under pulse condition .19
4.8 Capacitance .20

61051-1 © IEC:2007(E) – 3 –
4.9 Voltage proof (for insulated varistors only) .20

4.9.1 V-block method .20

4.9.2 Metal ball method .20

4.9.3 Foil method .21

4.10 Insulation resistance (for insulated varistors only) .21

4.10.1 Test procedure .21

4.10.2 Measurement and requirements.21

4.11 Robustness of terminations .22

4.11.1 General .22

4.11.2 Test Ua – Tensile .22

4.11.3 Test Ub – Bending (half of the number of terminations) .22
4.11.4 Test Uc – Torsion (other half of the number of terminations).22
4.11.5 Test Ud – Torque (for terminations with threaded studs or screws
and for integral mounting devices) .22
4.11.6 Visual examination .22
4.11.7 Final measurement .22
4.12 Resistance to soldering heat .23
4.12.1 Preconditioning.23
4.12.2 Test procedure .23
4.12.3 Recovery .23
4.12.4 Final inspection, measurement and requirements .23
4.13 Solderability .23
4.13.1 Test procedure .23
4.13.2 Final inspection, measurements and requirements .24
4.14 Rapid change of temperature .24
4.14.1 Initial measurement .24
4.14.2 Test procedure .24
4.14.3 Final inspection, measurement and requirements .24
4.15 Bump .25
4.15.1 Initial measurement .25
4.15.2 Test procedure .25
4.15.3 Final inspection, measurement and requirements .25
4.16 Shock.25
4.16.1 Initial measurement .25
4.16.2 Test procedure .25

4.16.3 Final inspection, measurement and requirements .25
4.17 Vibration.25
4.17.1 Initial measurement .25
4.17.2 Test procedure .26
4.17.3 Final inspection, measurement and requirements .26
4.18 Climatic sequence .26
4.18.1 Initial measurement .26
4.18.2 Dry heat .26
4.18.3 Damp heat, cyclic, Test Db, first cycle .26
4.18.4 Cold .26
4.18.5 Low air pressure.26
4.18.6 Damp heat, cyclic, Test Db, remaining cycles .26
4.18.7 Final inspection, measurement and requirements .27
4.19 Damp heat, steady state.27

– 4 – 61051-1 © IEC:2007(E)
4.19.1 Initial measurement .27

4.19.2 Test procedure .27

4.19.3 Final inspection, measurement and requirements .27

4.20 Fire hazard.28

4.21 Endurance at upper category temperature.28

4.22 Solvent resistance of marking.29

4.22.1 Test procedure .29

4.22.2 Requirements .29

4.23 Component solvent resistance.29

4.23.1 Initial measurements .29

4.23.2 Test procedure .
...

IEC 61051-1 ®
Edition 2.0 2007-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Varistors for use in electronic equipment –
Part 1: Generic specification
Varistances utilisées dans les équipements électroniques –
Partie 1: Spécification générique

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.

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utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et les

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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
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latest edition, a corrigenda or an amendment might have been published.

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IEC 61051-1 ®
Edition 2.0 2007-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Varistors for use in electronic equipment –

Part 1: Generic specification
Varistances utilisées dans les équipements électroniques –

Partie 1: Spécification générique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX V
ICS 31.040.99 ISBN 978-2-83220-138-1

– 2 – 61051-1  IEC:2007
CONTENTS
FOREWORD . 5

1 General . 7

1.1 Scope . 7

1.2 Object . 7

1.3 Normative references . 7

2 Technical data . 8

2.1 Units, symbols and terminology . 8
2.2 Terms and definitions . 9
2.3 Preferred values and characteristics . 13
2.4 Marking . 13
2.4.1 General . 13
2.4.2 Coding . 14
3 Quality assessment procedures . 14
3.1 Qualification approval/quality assessment systems . 14
3.2 Primary stage of manufacture . 14
3.3 Structurally similar components . 14
3.4 Qualification approval procedures . 15
3.5 Quality conformance inspection . 15
3.5.1 Certified records of released lots . 15
3.5.2 Delayed delivery . 15
3.5.3 Release for delivery before the completion of Group B tests . 16
3.6 Alternative test methods . 16
3.7 Unchecked parameters . 16
4 Test and measurement procedures . 16
4.1 General . 16
4.2 Standard atmospheric conditions . 16
4.2.1 Standard atmospheric conditions for testing . 16
4.2.2 Recovery conditions . 17
4.2.3 Referee conditions . 17
4.2.4 Reference conditions . 17
4.3 Drying and recovery . 17
4.4 Visual examination and check of dimensions . 18

4.4.1 Visual examination . 18
4.4.2 Marking . 18
4.4.3 Dimensions (gauging) . 18
4.4.4 Dimensions (detail) . 18
4.5 Nominal varistor voltage or leakage current (not applicable to pulse
measurements) . 18
4.5.1 Test procedure . 18
4.5.2 Measurement and requirements. 18
4.6 Pulse current . 18
4.6.1 Standard pulse currents . 19
4.6.2 Tolerances . 19
4.6.3 Measurement of the pulse current . 19
4.7 Voltage under pulse condition . 19
4.8 Capacitance . 20

61051-1  IEC:2007 – 3 –
4.9 Voltage proof (for insulated varistors only) . 20

4.9.1 V-block method . 20

4.9.2 Metal ball method . 20

4.9.3 Foil method . 21

4.10 Insulation resistance (for insulated varistors only) . 21

4.10.1 Test procedure . 21

4.10.2 Measurement and requirements. 21

4.11 Robustness of terminations . 22

4.11.1 General . 22

4.11.2 Test Ua – Tensile . 22

4.11.3 Test Ub – Bending (half of the number of terminations) . 22
4.11.4 Test Uc – Torsion (other half of the number of terminations) . 22
4.11.5 Test Ud – Torque (for terminations with threaded studs or screws
and for integral mounting devices) . 22
4.11.6 Visual examination . 22
4.11.7 Final measurement . 22
4.12 Resistance to soldering heat . 23
4.12.1 Preconditioning. 23
4.12.2 Test procedure . 23
4.12.3 Recovery . 23
4.12.4 Final inspection, measurement and requirements . 23
4.13 Solderability . 23
4.13.1 Test procedure . 23
4.13.2 Final inspection, measurements and requirements . 24
4.14 Rapid change of temperature . 24
4.14.1 Initial measurement . 24
4.14.2 Test procedure . 24
4.14.3 Final inspection, measurement and requirements . 24
4.15 Bump . 25
4.15.1 Initial measurement . 25
4.15.2 Test procedure . 25
4.15.3 Final inspection, measurement and requirements . 25
4.16 Shock . 25
4.16.1 Initial me
...