IEC TS 60721-4-3:2023

Classification of environmental conditions - Part 4-3: Guidance for the correlation and transformation of environmental condition classes of IEC 60721-3 to the environmental tests of IEC 60068 - Stationary use at weatherprotected locations

IEC TS 60721-4-3:2023 This part of IEC 60721 deals with the correlation and transformation of the conditions given in IEC 60721-3-3 to the environmental test procedures defined in IEC 60068-2.
This document provides test procedures and test severities for electrotechnical equipment operated at stationary weatherprotected locations for the product classes set out in IEC 60721-3-3.
This first edition cancels and replaces IEC TR 60721-4-3:2001 and IEC TR 60721-4-3:2001/AMD1:2003. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to IEC TR 60721-4-3:2001 and IEC TR 60721-4-3:2001/AMD1:2003:
a) the document has been totally reworked;
b) all figures have been removed, except in Annex A;
c) severities have been aligned with those of IEC 60721-3-3:2019.

General Information

• Status: Published
• Publication Date: 26-Jul-2023
• ICS: 19.040 - Environmental testing
• Technical Committee: TC 104 - Environmental conditions, classification and methods of test
• Drafting Committee: WG 14 - TC 104/WG 14
• Current Stage: PPUB - Publication issued
• Start Date: 01-Aug-2023
• Completion Date: 27-Jul-2023

Relations

• Revises: IEC TR 60721-4-3:2001/AMD1:2003 - Amendment 1 - Classification of environmental conditions - Part 4-3: Guidance for the correlation and transformation of environmental condition classes of IEC 60721-3 to the environmental tests of IEC 60068 - Stationary use at weatherprotected locations
• Effective Date: 05-Sep-2023
• Revises: IEC TR 60721-4-3:2001 - Classification of environmental conditions - Part 4-3: Guidance for the correlation and transformation of environmental condition classes of IEC 60721-3 to the environmental tests of IEC 60068 - Stationary use at weatherprotected locations
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TS 60721-4-3 ®
Edition 1.0 2023-07
TECHNICAL
SPECIFICATION
Classification of environmental conditions –
Part 4-3: Guidance for the correlation and transformation of environmental
condition classes of IEC 60721-3 to the environmental tests of IEC 60068 –
Stationary use at weatherprotected locations

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IEC TS 60721-4-3 ®
Edition 1.0 2023-07
TECHNICAL
SPECIFICATION
Classification of environmental conditions –

Part 4-3: Guidance for the correlation and transformation of environmental

condition classes of IEC 60721-3 to the environmental tests of IEC 60068 –

Stationary use at weatherprotected locations

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS  19.040 ISBN 978-2-8322-7300-5

− 2 − IEC TS 60721-4-3:2023  IEC 2023
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 General . 7
4.1 General remarks concerning IEC 60721-3-3 . 7
4.2 General remarks concerning the IEC 60068-2 series . 7
4.3 Recommended test procedures and severities . 7
4.4 Environmental tests for in-use classes . 7
4.5 Test durations . 8
4.6 Ambient . 8
5 Climate conditions, classes 3K20 to 3K24 from IEC 60721-3-3 . 8
5.1 Class 3K20 (fully air-conditioned enclosed locations) . 8
5.2 Class 3K21 (continuously temperature-controlled enclosed locations) . 8
5.3 Class 3K22 (temperature-controlled enclosed locations) . 10
5.4 Class 3K23 (enclosed locations having no temperature or humidity control) . 12
5.5 Class 3K24 (enclosed locations having neither temperature nor humidity
control) . 14
6 Special climate conditions, classes 3Z12 to 3Z14 from IEC 60721-3-3 . 16
7 Biological conditions, classes 3B1 to 3B3 from IEC 60721-3-3 . 16
8 Mechanical conditions, classes 3M10 to 3M12 from IEC 60721-3-3 . 17
Annex A (informative) Interdependence of air temperature, relative air humidity, and
absolute air humidity . 18
Bibliography . 19

Figure A.1 – Climatogram of interdependence of air temperature, relative air humidity,
and absolute air humidity . 18

Table 1 – Class 3K21 (continuously temperature-controlled enclosed locations) . 8
Table 2 – Class 3K22 (temperature-controlled enclosed locations) . 10
Table 3 – Class 3K23 (enclosed locations having no temperature or humidity control) . 12
Table 4 – Class 3K24 (enclosed locations having neither temperature nor humidity
control) . 14
Table 5 – Class 3Z12 to 3Z14 . 16
Table 6 – Class 3B1 to 3B3 . 16
Table 7 – Class 3M10 to 3M12 . 17

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CLASSIFICATION OF ENVIRONMENTAL CONDITIONS –

Part 4-3: Guidance for the correlation and transformation of
environmental condition classes of IEC 60721-3 to the environmental tests
of IEC 60068 – Stationary use at weatherprotected locations

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
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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IEC TS 60721-4-3 has been prepared by IEC technical committee 104: Environmental
conditions, classification, and methods of test. It is a Technical Specification.
This first edition cancels and replaces IEC TR 60721-4-3:2001 and IEC TR 60721-4-
3:2001/AMD1:2003. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to
IEC TR 60721-4-3:2001 and IEC TR 60721-4-3:2001/AMD1:2003:
a) the document has been totally reworked;
b) all figures have been removed, except in Annex A;

− 4 − IEC TS 60721-4-3:2023  IEC 2023
c) severities have been aligned with those of IEC 60721-3-3:2019.
The text of this Technical Specification is based on the following documents:
Draft Report on voting
104/977/DTS 104/1014/RVDTS
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 Technical Specification 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, availa-
ble at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 60721 series, published under the general title Classification of
environmental conditions, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
INTRODUCTION
It is essential to emphasize the guidance nature of this document since it is virtually
impossible to specify mandatory requirements for worldwide use. However, for those cases
which require different tests from those recommended in this document, the guidance given
should establish principles and methodology to determine alternative tests.
The reasons for correlation are provided to enable specification writers to modify a test if their
application warrants it.
− 6 − IEC TS 60721-4-3:2023  IEC 2023
CLASSIFICATION OF ENVIRONMENTAL CONDITIONS –

Part 4-3: Guidance for the correlation and transformation of
environmental condition classes of IEC 60721-3 to the environmental tests
of IEC 60068 – Stationary use at weatherprotected locations

1 Scope
This part of IEC 60721 deals with the correlation and transformation of the conditions given in
IEC 60721-3-3 to the environmental test procedures defined in IEC 60068-2.
This document provides test procedures and test severities for electrotechnical equipment
operated at stationary weatherprotected locations for the product classes set out in
IEC 60721-3-3.
An environment can consist of several environmental conditions such as dynamic, climatic,
and
...