IEC 60664-3:2016

Insulation coordination for equipment within low-voltage systems - Part 3: Use of coating, potting or moulding for protection against pollution

IEC 60664-3:2016 applies to assemblies protected against pollution by the use of coating, potting or moulding, thus allowing a reduction of clearance and creepage distances as described in IEC 60664-1. This document describes the requirements and test procedures for two methods of protection:
- type 1 protection improves the microenvironment of the parts under the protection;
- type 2 protection is considered to be similar to solid insulation. This edition includes the following significant technical changes with respect to the previous edition:
a) information added concerning interpolation;
b) provided scratch test is only for type 2 protection;
c) renumbered the scratch test to follow the visual examination test, since it makes more sense there;
d) separated the tables under what is now called Annex A, to make them clearer.

Coordination de l'isolement des matériels dans les systèmes (réseaux) à basse tension - Partie 3: Utilisation de revêtement, d'empotage ou de moulage pour la protection contre la pollution

L'IEC 60664-3:2016 est applicable aux ensembles protégés contre la pollution au moyen de revêtement, d'empotage ou de moulage, permettant ainsi une réduction des distances d'isolement et des lignes de fuite décrites dans l'IEC 60664-1. Le présent document décrit les exigences et procédures d'essai pour deux méthodes de protection:
- la protection de type 1 améliore le microenvironnement des parties sous protection;
- la protection de type 2 est considérée comme similaire à l'isolation solide. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) des informations concernant l'interpolation ont été ajoutées;
b) l'essai de résistance aux éraflures est destiné uniquement aux protections de type 2;
c) l'essai de résistance aux éraflures a été renuméroté et placé à la suite de l'essai d'examen visuel, ce qui est plus pertinent;
d) le tableau de l'annexe désormais désignée comme l'Annexe A a été divisé en plusieurs tableaux, pour plus de clarté.

General Information

• Status: Published
• Publication Date: 03-Nov-2016
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.080.30 - Insulation systems
• Technical Committee: TC 109 - Insulation co-ordination for low-voltage equipment
• Drafting Committee: MT 2 - TC 109/MT 2
• Current Stage: PPUB - Publication issued
• Start Date: 30-Nov-2016
• Completion Date: 04-Nov-2016

Relations

• Revises: IEC 60664-3:2003 - Insulation coordination for equipment within low-voltage systems - Part 3: Use of coating, potting or moulding for protection against pollution
• Effective Date: 05-Sep-2023
• Revises: IEC 60664-3:2003/AMD1:2010 - Amendment 1 - Insulation coordination for equipment within low-voltage systems - Part 3: Use of coating, potting or moulding for protection against pollution
• Effective Date: 05-Sep-2023
• Revises: IEC 60664-3:2003/AMD1:2010/COR1:2010 - Corrigendum 1 to amendment 1 - Insulation coordination for equipment within low-voltage systems - Part 3: Use of coating, potting or moulding for protection against pollution
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60664-3 ®
Edition 3.0 2016-11
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
BASIC SAFETY PUBLICATION
Insulation coordination for equipment within low-voltage systems –
Part 3: Use of coating, potting or moulding for protection against pollution

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.: [phone]
3, rue de Varembé Fax: [phone]
CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
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
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IEC 60664-3 ®
Edition 3.0 2016-11
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
BASIC SAFETY PUBLICATION
Insulation coordination for equipment within low-voltage systems –

Part 3: Use of coating, potting or moulding for protection against pollution

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.080.30 ISBN 978-2-8322-3738-0

– 2 – IEC 60664-3:2016 RLV © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Design requirements . 10
4.1 Principles . 10
4.2 Application range regarding with regards to the environment . 10
4.3 Requirements for the types of protection . 10
4.4 Dimensioning procedures . 10
5 Tests . 11
5.1 General . 11
5.2 Specimens for testing coatings . 12
5.3 Specimens for testing mouldings and potting . 12
5.4 Preparation of test specimens . 12
5.5 Visual examination . 12
5.6 Scratch-resistance test . 12
5.7 Conditioning of the test specimens . 13
5.7.1 General . 13
5.7.2 Cold conditioning . 13
5.7.3 Dry-heat conditioning . 14
5.7.4 Rapid change of temperature . 14
5.7.5 Damp heat, steady-state with polarizing voltage . 15
5.8 Mechanical and electrical tests after conditioning and electromigration . 15
5.8.1 General test conditions . 15
5.8.2 Adhesion of coating . 16
5.8.3 Insulation resistance between conductors . 16
5.8.4 AC withstand Voltage test . 16
5.8.5 Partial discharge extinction voltage . 17
5.9 Additional tests . 17
5.9.1 General . 17
5.9.2 Resistance to soldering heat . 17
5.9.3 Flammability . 17
5.9.4 Solvent resistance . 17
Annex A (normative) Test sequences . 18
Annex B (normative) Decisions to be taken by the technical committees’ decisions . 21
B.1 General . 21
B.2 Decisions required by technical committees . 21
B.3 Optional test conditions. 21
Annex C (normative) Printed wiring board for testing coatings . 22
C.1 General . 22
C.2 Specification of the printed wiring board. 22
C.3 Arrangement of the conductors . 22
C.4 Arrangement of lands . 23
C.5 Connections for the tests . 23

Bibliography . 26

Figure 1 – Scratch-resistance test for protecting layers . 13
Figure C.1 – Configuration of the test specimen . 24
Figure C.2 – Configuration of lands and adjacent conductors . 25

Table 1 – Minimum spacings for type 2 protection . 11
Table 2 – Dry-heat conditioning . 14
Table 3 – Degrees of severities for rapid change of temperature . 15
Table A.1 – Test sequence 1 . 18
Table A.2 – Test sequence 2 additional conditioning with respect to electromigration . 19
Table A.3 – Additional tests . 20

– 4 – IEC 60664-3:2016 RLV © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INSULATION COORDINATION FOR EQUIPMENT
WITHIN LOW-VOLTAGE SYSTEMS –
Part 3: Use of coating, potting or moulding
for protection against pollution

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,
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International Standard IEC 60664-3 has been prepared by IEC technical committee TC 109:
Insulation co-ordination for low-voltage equipment.
It has the status of a basic safety publication in accordance with IEC Guide 104.
This third edition cancels and replaces the second edition published in 2003 and Amendment
1:2010. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) information added concer
...

IEC 60664-3 ®
Edition 3.0 2016-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Insulation coordination for equipment within low-voltage systems –
Part 3: Use of coating, potting or moulding for protection against pollution

Coordination de l'isolement des matériels dans les systèmes (réseaux) à basse
tension –
Partie 3: Utilisation de revêtement, d'empotage ou de moulage pour la protection
contre la pollution
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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Switzerland www.iec.ch
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 corrigenda or an amendment might have been published.

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documents. Available for PC, Mac OS, Android Tablets and languages. Also known as the International Electrotechnical
iPad. Vocabulary (IEV) online.

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The advanced search enables to find IEC publications by a 65 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of
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and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

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IEC 60664-3 ®
Edition 3.0 2016-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ

Insulation coordination for equipment within low-voltage systems –

Part 3: Use of coating, potting or moulding for protection against pollution

Coordination de l'isolement des matériels dans les systèmes (réseaux) à basse

tension –
Partie 3: Utilisation de revêtement, d'empotage ou de moulage pour la protection

contre la pollution
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.080.30 ISBN 978-2-8322-3693-2

– 2 – IEC 60664-3:2016 © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Design requirements . 9
4.1 Principles . 9
4.2 Application range with regards to the environment . 9
4.3 Requirements for the types of protection . 10
4.4 Dimensioning procedures . 10
5 Tests . 11
5.1 General . 11
5.2 Specimens for testing coatings . 11
5.3 Specimens for testing mouldings and potting . 12
5.4 Preparation of test specimens . 12
5.5 Visual examination . 12
5.6 Scratch-resistance test . 12
5.7 Conditioning of the test specimens . 13
5.7.1 General . 13
5.7.2 Cold conditioning . 13
5.7.3 Dry-heat conditioning . 13
5.7.4 Rapid change of temperature . 14
5.7.5 Damp heat, steady-state with polarizing voltage . 15
5.8 Mechanical and electrical tests after conditioning and electromigration . 15
5.8.1 General test conditions . 15
5.8.2 Adhesion of coating . 15
5.8.3 Insulation resistance between conductors . 16
5.8.4 Voltage test . 16
5.8.5 Partial discharge extinction voltage . 16
5.9 Additional tests . 16
5.9.1 General . 16
5.9.2 Resistance to soldering heat . 17
5.9.3 Flammability . 17
5.9.4 Solvent resistance . 17
Annex A (normative) Test sequences . 18
Annex B (normative) Decisions to be taken by the technical committees . 20
B.1 General . 20
B.2 Decisions required by technical committees . 20
B.3 Optional test conditions. 20
Annex C (normative) Printed wiring board for testing coatings . 21
C.1 General . 21
C.2 Specification of the printed wiring board. 21
C.3 Arrangement of the conductors . 21
C.4 Arrangement of lands . 22
C.5 Connections for the tests . 22
Bibliography . 25

Figure 1 – Scratch-resistance test for protecting layers . 13
Figure C.1 – Configuration of the test specimen . 23
Figure C.2 – Configuration of lands and adjacent conductors . 24

Table 1 – Minimum spacings for type 2 protection . 10
Table 2 – Dry-heat conditioning . 14
Table 3 – Degrees of severities for rapid change of temperature . 14
Table A.1 – Test sequence 1 . 18
Table A.2 – Test sequence 2 additional conditioning with respect to electromigration . 19
Table A.3 – Additional tests . 19

– 4 – IEC 60664-3:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INSULATION COORDINATION FOR EQUIPMENT
WITHIN LOW-VOLTAGE SYSTEMS –
Part 3: Use of coating, potting or moulding
for protection against pollution

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
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non
...