IEC 60721-3-9:2024
(Main)Classification of environmental conditions - Part 3-9: Classification of groups of environmental parameters and their severities - Microclimates inside products
Classification of environmental conditions - Part 3-9: Classification of groups of environmental parameters and their severities - Microclimates inside products
IEC 60721-3-9:2024 classifies groups of microclimatic conditions, to which components (basic parts, assemblies, built-in units) can be subjected inside products, which are used under the climatic conditions as classified in IEC 60721-3-3 and IEC 60721-3-4.
This second edition cancels and replaces the first edition published in 1993, Amendment 1:1994 and Corrigendum 1:1995. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) Clause 2 has been updated;
b) Clause 4 has been re-edited and simplified;
c) Annex A has been revised and updated;
d) a new Annex B has been added and gives the origin of the constitutional diagram for humid air, which is the basis of drawing the climatogram for a microclimate.
Classification des conditions d'environnement - Partie 3-9: Classification des groupements des agents d'environnement et de leurs sévérités - Microclimats à l'intérieur des produits
L'IEC 60721-3-9:2024 classifie les groupements des conditions microclimatiques auxquelles les composants (parties élémentaires, assemblées, encastrées) peuvent être soumis à l'intérieur des produits, lorsqu'ils sont utilisés dans les conditions climatiques classifiées dans l'IEC 60721-3-3 et l'IEC 60721-3-4.
Cette deuxième édition annule et remplace la première édition parue en 1993, l’Amendement 1:1994 et le Corrigendum 1:1995. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) l’Article 2 a été mis à jour;
b) l’Article 4 a été reformulé et simplifié;
c) l’Annexe A a été révisée et mise à jour;
d) une nouvelle Annexe B a été ajoutée et fournit l'origine du diagramme constitutionnel pour l'humidité de l'air, qui sert de base à l'établissement du climatogramme d'un microclimat.
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IEC 60721-3-9 ®
Edition 2.0 2024-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions –
Part 3-9: Classification of groups of environmental parameters and their
severities – Microclimates inside products
Classification des conditions d'environnement –
Partie 3-9: Classification des groupements des agents d'environnement et de
leurs sévérités – Microclimats à l'intérieur des produits
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IEC 60721-3-9 ®
Edition 2.0 2024-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions –
Part 3-9: Classification of groups of environmental parameters and their
severities – Microclimates inside products
Classification des conditions d'environnement –
Partie 3-9: Classification des groupements des agents d'environnement et de
leurs sévérités – Microclimats à l'intérieur des produits
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 19.040 ISBN 978-2-8322-8626-5
– 2 – IEC 60721-3-9:2024 © IEC 2024
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 General . 6
5 Classification of microclimatic conditions . 6
6 Types and marking of microclimatic classes . 7
Annex A (informative) Graphical representation and preferred microclimatic classes . 8
A.1 Graphical representation of the microclimatic classes . 8
A.2 Tables of preferred microclimatic classes . 9
Annex B (informative) Constitutional diagram for humid air . 14
B.1 General . 14
B.2 Application . 14
B.3 Description . 14
Bibliography . 17
Figure A.1 – Example of a climatogram for a microclimate: Microclimatic class
3K22/X2/Y1 . 9
Figure B.1 – Constitutional diagram for humid air . 16
Table 1 – Classification of microclimatic conditions . 7
Table A.1 – Characteristic parameters and severities of microclimatic classes –
Weatherprotected locations: Corner points A’, B’, C’, D’, E’ and F’ . 10
Table A.2 – Characteristic parameters and severities of microclimatic classes –
Weatherprotected locations: Corner points B to B and C to C . 11
Y1 Y4 Y1 Y4
Table A.3 – Characteristic parameters and severities of microclimatic classes –
Non-weatherprotected locations: Corner points A’, B’, C’, D’, E’ and F’ . 12
Table A.4 – Characteristic parameters and severities of microclimatic classes –
Non-weatherprotected locations: Corner points B to B and C to C . 13
Y1 Y4 Y1 Y4
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CLASSIFICATION OF ENVIRONMENTAL CONDITIONS –
Part 3-9: Classification of groups of environmental parameters
and their severities – Microclimates inside products
FOREWORD
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IEC 60721-3-9 has been prepared by IEC technical committee 104: Environmental conditions,
classification and methods of test. It is an International Standard.
This second edition cancels and replaces the first edition published in 1993, Amendment 1:1994
and Corrigendum 1:1995. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Clause 2 has been updated;
b) Clause 4 has been re-edited and simplified;
c) Annex A has been revised and updated;
– 4 – IEC 60721-3-9:2024 © IEC 2024
d) a new Annex B has been added and gives the origin of the constitutional diagram for humid
air, which is the basis of drawing the climatogram for a microclimate.
The text of this International Standard is based on the following documents:
Draft Report on voting
104/1041/FDIS 104/1050/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detai
...
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