IEC 62631-3-3:2015

IEC 62631-3-3 ®
Edition 1.0 2015-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dielectric and resistive properties of solid insulating materials –
Part 3-3: Determination of resistive properties (DC methods) – Insulation
resistance
Propriétés diélectriques et résistives des matériaux isolants solides –
Partie 3-3: Détermination des propriétés résistives (méthodes en courant
continu) – Résistance d'isolement

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IEC 62631-3-3 ®
Edition 1.0 2015-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dielectric and resistive properties of solid insulating materials –

Part 3-3: Determination of resistive properties (DC methods) – Insulation

resistance
Propriétés diélectriques et résistives des matériaux isolants solides –

Partie 3-3: Détermination des propriétés résistives (méthodes en courant

continu) – Résistance d'isolement

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.99; 29.035.01 ISBN 978-2-8322-3024-4

– 2 – IEC 62631-3-3:2015 © IEC 2015
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Significance . 8
5 Method of test . 9
5.1 General . 9
5.2 Test conditions . 9
5.2.1 Voltage . 9
5.2.2 Electrode material . 9
5.3 Equipment . 10
5.3.1 General . 10
5.3.2 Accuracy . 10
5.3.3 Voltage source . 10
5.4 Calibration . 10
5.5 Test specimen . 11
5.5.1 Dimensions of test specimen . 11
5.5.2 Test specimen for insulating resistance between tapered pin electrodes . 11
5.5.3 Test specimen for insulating resistance between bar electrodes . 11
5.5.4 Manufacturing of test specimen . 11
5.5.5 Number of test specimen . 12
5.5.6 Conditioning and pre-treatment of test specimen . 12
5.6 Electrode application . 12
5.6.1 Application of tapered pin electrodes . 12
5.6.2 Application of bar electrodes . 13
5.7 Test procedure . 14
5.8 Evaluation . 14
5.8.1 Insulating resistance between tapered pin electrodes . 14
5.8.2 Insulating resistance between bar electrodes . 14
6 Test report . 14
7 Repeatability and reproducibility . 15
Bibliography . 16

Figure 1 – Pin electrode arrangements . 6
Figure 2 – Bar electrode arrangement . 7
Figure 3 – Specimen for measurement of the insulation resistance R between plugs . 13
I
Table 1 – Composition of electrode steel . 10

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIELECTRIC AND RESISTIVE PROPERTIES
OF SOLID INSULATING MATERIALS –

Part 3-3: Determination of resistive properties (DC methods) –
Insulation resistance
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
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62631-3-3 has been prepared by IEC technical committee 112:
Evaluation and qualification of electrical insulating materials and systems.
This first edition cancels and replaces the first edition of IEC 60167, published in 1964, and
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the first
edition of IEC 60167:
a) IEC 60167 has been completely revised, both editorially and technically, and incorporated
into the new IEC 62631 series;
b) test methods have been updated to current day state of the art.

– 4 – IEC 62631-3-3:2015 © IEC 2015
The text of this standard is based on the following documents:
FDIS Report on voting
112/341/FDIS 112/352/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62631 series, published under the general title Dielectric and
resistive properties of solid insulating materials, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
DIELECTRIC AND RESISTIVE PROPERTIES
OF SOLID INSULATING MATERIALS –

Part 3-3: Determination of resistive properties (DC methods) –
Insulation resistance
1 Scope
This part of IEC 62631 covers methods of test for the determination of the insulation
resistance of electrical insulating materials or insulating systems by applying DC voltage.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60212, Standard conditions for use prior to and during the testing of solid electrical
insulating materials
IEC 60216-4-1, Electrical insulating materials − Thermal endurance properties – Part 4-1:
− Single-chamber ovens
Ageing ovens
ISO 2339, Taper pins, unhardened
ISO 3465, Hand taper pin reamers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
electrode arrangement
arrangement of two electrically conductive bodies in contact with the surface and the bulk
volume of a test specimen
3.1.1
tapered pin electrodes
electrode arrangement using tapered pin electrodes
Note 1 to entry: See Figure 1.
3.1.2
bar electrodes
electrode arrangement using bar electrodes
Note 1 to entry: See Figure 2.

– 6 – IEC 62631-3-3:2015 © IEC 2015
Dimensions in millimetres
25 min. 25±1 25 min.
IEC
Figure 1a – Test specimen arrangement for plates
Dimensions in millimetres
60 min. 20 min.
IEC
Figure 1b – Test specimen arrangement for pipes and rods
Figure 1 – Pin electrode arrangements
25 min.
Dimensions in millimetres
Metal electrodes
25±0,5
Screws
with nuts
Test
specimen
Insulating
material
Guarded metal
support
Metal electrodes
Test specimen
25±0,5 10
IEC
Figure 2 – Bar electrode arrangement
– 8 – IEC 62631-3-3:2015 © IEC 2015
3.2
measured resistance
ratio of DC voltage applied to an electrode arrangement in contact with a test specimen to the
current between them measured with sufficient precision
Note 1 to entry: A Wheatstone bridge may also be used to compare the measured resistor with a standard
resistor. However, Wheatstone bridges are not commonly used anymore.
Note 2 to entry: According to IEC 60050-121[1] : Electromagnetism, “conductivity” is defined as “scalar or tensor
quantity the product of which by the electric field strength in a medium is equal to the electric current density” and
“resistivity” as “the inverse of the conductivity when this inverse exists”. Measured in this way, the insulating
resistance is an average of the integrated resistivity over possible heterogeneities in the volume incorporated in
the measurement; it includes the effect of possible polarization phenomena at the electrodes.
3.3
insulation resistance
R
I
measured resistance between any electrode arrangement defined by this standard
Note 1 to entry: Dependent on the electrode arrangement used it is designated as R or R , with insulation
IT IR
resistance, R expressed by the unit Ω.
I
3.3.1
R
IT
insulation resistance between tapered pin electrodes
measured resistance using the tapered pin electrode arrangement in contact with a test
specimen defined by this standard
Note 1 to entry: Tapered pin electrodes are mainly in contact with the bulk volume of the test specimen but the
surface also contributes to the measured insulation resistance.
3.3.2
R
IB
insulation resistance between bar electrodes
measured resistance using the bar electrode arrangement in contact with a test specimen
defined by this standard
Note 1 to entry: Bar electrodes are mainly in contact with the surface of the test specimen but the bulk volume
also contributes to the measured insulation resistance.
4 Significance
Insulating materials are used in general to electrically isolate components of an electrical
system from each other and from earth. Solid insulating materials can also provide
mechanical support. For these purposes it is generally desirable to have the insulation
resistance as high as possible, consistent with acceptable mechanical, chemical and heat
resistance properties.
Insulation resistance R is defined in this standard in two distinct ways: between tapered pin
I
electrodes R and between bar electrodes R .
IT’ IB
NOTE 1 Determination of R and R on one and the same insulating material does not lead to comparable
IT IB
results.
Both are to be regarded as technical useful quantities, characterizing the overall resistive
properties of an electrical insulating material or a product made from it. Insulation resistance
contains both, volume resistance (see IEC 62631-3-1[2]) and surface resistance (see
IEC 62631-3-2[3]) in differing portions, dependent on the specimen under test and its
condition.
___________
Numbers in square brackets refer to the Bibliography.

NOTE 2 In the past, resistance measured between specified line electrodes had also been designated as
insulating resistance. This kind of resistance can be found as surface resistance between line electrodes R in
SD
IEC 62631-3-2.
To achieve comparable results, insulating resistance shall be measured under fixed
geometrical conditions, as stipulated in this standard. Under these conditions, it may be used
to compare different insulating materials or products, considering that this approach only
permits a simplified classification.
NOTE 3 Insulating resistance R defined by this standard is not identical with the resistances between conducting
I
bodies within electric equipment, separated by electrical insulating materials. However, it can be useful for basic
design considerations.
5 Method of test
5.1 General
The measurement of insulation resistances shall be carried out carefully and with due
consideration for the electric properties of the measuring circuit as well as the specific electric
properties of the material.
To carry out the test, in most cases the use of high voltages is necessary. Care shall be
taken, to prevent from electric shock.
Polarization effects may influence the measurement. Therefore it is not acceptable to achieve
the measured resistance twice in two consecutive experiments without a sufficient space of
time in between.
NOTE For materials with an insulating resistance of not more than 10 Ω, a period of 1 h after voltage application
might be sufficient.
5.2 Test conditions
5.2.1 Voltage
The measuring voltage shall preferably be
10 V, 100 V, 500 V, 1 000 V, 10 000 V.
Other voltages may be applicable. If not otherwise stipulated, a voltage of 100 V shall be
used.
NOTE 1 Partial discharges can lead to erroneous measurements when a specific inception voltage is exceeded.
In air, below 340 V no partial discharges will occur.
-5
NOTE 2 The ripple of the voltage source is important. A typical value for 100 V is <5 × 10 peak to peak.
5.2.2 Electrode material
Stainless steel with the composition as given in Table 1, shall be used as the electrode
material. Other materials are acceptable if their equivalence has been proven.

– 10 – IEC 62631-3-3:2015 © IEC 2015
Table 1 – Composition of electrode steel
Chemical elements Content
%
C Max. 0,07
Si Max. 1,00
Mn Max. 2,00
P Max. 0,045
S Max. 0,015
N Max. 0,11
Cr 17,00 to 19,50
NOTE This steel is known as X5CrNi18-10, as stipulated in EN 10088-2[4].The grade is also known as material
number 1.4301. A similar grade with slightly other composition is known as AISI 304. For further information see [5]
and [6].
When using bar electrodes for the determination of insulating resistance, in case of rigid test
specimen, a tin foil (99 % tin) shall be used to provide proper contact.
5.3 Equipment
5.3.1 General
Care should be taken that the insulating resistance is not negatively influenced by parasitic
resistances parallel to the electrode arrangement, such as the resistance of test supports or
cable isolation.
To prevent measuring errors for measured resistances higher than 10 Ω, shielded cables
and shielded measuring cabinets shall be used.
5.3.2 Accuracy
Any suitable equipment may be used. The measuring device should be capable of
determining the unknown resistance with an overall accuracy of at least:
• ±10 % for resistance below 10 Ω,
10 14
• ±20 % for resistance between 10 Ω and 10 Ω,
• ±50 % for values higher than 10 Ω.
5.3.3 Voltage source
A source of very steady direct voltage is required. This can be provided either by batteries or
by rectified and stabilized power supply. The degree of stability required is such that the
change in current due to any change in voltage is negligible compared with the current to be
measured.
5.4 Calibration
The equipment shall be calibrated in the magnitude of the volume resistance measured.
NOTE Calibration resistors in the range up to 100 TΩ are commercially available.

5.5 Test specimen
5.5.1 Dimensions of test specimen
As insulation resistance combines volume and surface properties of an insulating material, the
dimensions of a test specimen will influence the results, because the ratio between volume
and surface may differ.
In case of doubt, the dimension shall be agreed with the customer. Unless otherwise
stipulated in the relevant product standard, the following dimensions for test specimen are
recommended.
5.5.2 Test specimen for insulating resistance between tapered pin electrodes
5.5.2.1 Sheet materials
The sheet materials shall measure ≥ 60 mm × ≥ 15 mm × sheet thickness (see Figure 1 and
Figure 3).
5.5.2.2 Pipes, bars and rods
These shall comprise ≥ 60 mm long sections from the cross-section of the product (see
Figure 1).
In the case of pipes, at larger outer diameters than 110 mm, subsections
≥ 60 mm × ≥ 15 mm × wall thickness may be cut from the pipe. In case of doubt, the
measurement should be carried out on the complete pipe.
5.5.2.3 Any other shapes
Specimen shall be taken as appropriate.
5.5.3 Test specimen for insulating resistance between bar electrodes
5.5.3.1 Tapes, strips and thin rods
These shall comprise ≥ 50 mm long sections, ≤ 25,5 mm in width, cut from the product.
5.5.3.2 Any other shapes
Specimen shall be taken as appropriate.
5.5.4 Manufacturing of test specimen
The removal, production and shape of the test specimen shall be determined by the relevant
standards for the material. During removal and production of the specimen the condition of
the material shall not be changed and the specimen removed shall not be damaged.
If the surface of the test specimen is machined at the contact areas of the electrodes, the type
of machining shall be specified in the test report. The test specimen shall have a
geometrically simple shape (plate with parallel measuring areas, cylinder etc.).
In case of insulating resistance between tapered pin electrodes, the necessary holes shall be
drilled with a diameter of 5 mm of the driller. For reinforced materials a driller made from
− 0,1
sintered metal may be useful.
Specimen from products shall be prepared with the product thickness, if possible

– 12 – IEC 62631-3-3:2015 © IEC 2015
5.5.5 Number of test specimen
The number of specimen to be tested shall be determined by the relevant product standards.
If no such data is available, at least three specimen shall be tested.
5.5.6 Conditioning and pre-treatment of test specimen
Conditioning and any other pre-treatment of the test specimen shall be carried out according
to the relevant product standard.
If no product standard exists, conditioning shall be realised for at least 4 days at 23 °C and
50 % RH according to IEC 60212 (standard climate B).
In case of tapered pin electrodes the conditioning shall be done without inserted plugs.
If not otherwise stipulated, no cleaning of the test specimen shall be done. Any additional
contamination shall be avoided.
5.6 Electrode application
5.6.1 Application of tapered pin electrodes
5.6.1.1 General
Two metal taper pins of Type A − 5 × 50 (diameter of 5 mm and taper 1:50), according to
ISO 2339, arranged in parallel, shall be used as plug electrodes.
Unless otherwise specified, two continuous holes with a diameter of 5 mm and (25 ± 1) mm
between the centres shall be drilled in the test specimen at right angles to the surface to
receive the plug electrodes.
If it is not ensured that the tapered pins fit tightly in the holes, two holes with a diameter of
5 mm and (25 ±1) mm between the centres should be drilled at right angles to the surface to a
depth of about two-thirds of the thickness of the material, but at least to a depth of 10 mm.
These holes should be coated with graphite or conductive silver paint.
The holes can also be processed into moulded specimen. Both holes shall be reamed in the
opposite direction with a taper pin reamer according to ISO 3465 with a nominal diameter of
5 mm and the pins inserted with a tight fit.
After conditioning or any other pre-treatment the tapered pins shall be inserted with a tight fit
in the holes.
5.6.1.2 Sheet materials
The holes shall be drilled on the longitudinal centre line of the specimen area, i.e. symmetrical
with the centre of the longitudinal centre line (see Figure 1 and Figure 3).
5.6.1.3 Pipes, bars and rods
The holes shall be drilled on the longitudinal centre line on the sections, i.e. symmetrically
with the longitudinal centre line (see Figure 1 and Figure 3, where appropriate).
5.6.1.4 Any other shapes
The holes shall be drilled at a point where the specified distance between the hole centres
can be observed on a straight line.

Dimensions in millimetres
60 min.
Sheet thickness
15 min.
IEC
Figure 3 – Specimen for measurement of
the insulation resistance R between plugs
I
5.6.2 Application of bar electrodes
5.6.2.1 General
The bar electrodes form like two clamps 10 mm × 10 mm × 50 mm, which are fixed by screws
and nuts (see Figure 2). They are to be fixed in a distance of 25 mm between their inner
edges on the test specimen.
It is recommended to use a guarded metal support for the electrodes. This support shall be
connected to the electrodes by means of a insulating material with a volume resistance larger
than 10 Ωm. The guarding of the metal support shall provide that no current flowing in
parallel to the test specimen will influence the measurement (see 5.3).
If no guarded metal support is used, the test specimen shall be placed on an insulating plate
with a volume resistance lager than 10 Ωm.
NOTE Insulating materials such as polytetrafluoroethylene can be useful.
5.6.2.2 Tapes, strips and thin rods
A smooth contact shall be provided, comprising the complete surface area in touch with the
bar electrodes. In the case of rigid specimen, a tin foil (see 5.2.2) shall be placed between the
bar electrodes and the specimen's surface. The tin foil, however, shall not protrude out of the
bar electrodes.
After conditioning or any other pre-treatment of the specimen, it shall be placed in between
the bar electrode arrangement. The screws shall be tightened carefully in a diagonal
sequence to avoid damage of the test specimen, but with sufficient torque to provide a proper
contact. In case of doubt, comparison tests shall be carried out.

– 14 – IEC 62631-3-3:2015 © IEC 2015
5.6.2.3 Any other shapes
To be agreed with the customer.
5.7 Test procedure
Unless otherwise agreed, the measurement shall be conducted in normal air at 23 °C and
50 % RH according to IEC 60212 (standard climate B).
If the temperature-dependence of the insulation resistance is to be determined, the
measurements on the test specimen shall be conducted in a heating cabinet according to
IEC 60216-4-1.
The specimen shall be conditioned and pre-treated according to 5.5.6. Immediately after the
treatment, the electrodes shall be applied.
The test specimen shall be placed on an insulating underlay.
Subsequently, but no more than 2 min after finishing the conditioning or pre-treatment, the
insulating resistance R shall be determined between the electrodes. If not otherwise
I
stipulatetd, it shall be measured 1 min after voltage application.
5.8 Evaluation
5.8.1 Insulating resistance between tapered pin electrodes
R = R
IT I (1)
The insulating resistance between tapered pin electrodes R shall be specified in Ω.
IT
5.8.2 Insulating resistance between bar electrodes
R = R
IB I (2)
The insulating resistance between bar electrodes R shall be specified in Ω.
IB
6 Test report
The report shall include the following:
• complete identification and description of the material tested, including source and
manufacturer’s code;
• shape and thickness of test specimen (if the sample was cut out from a larger product
such as a pipe);
• test voltage;
• accuracy of the instrument and calibration method, depending on the measured values of
resistance;
• curing conditions of the material and any pre-treatment;
• conditioning of samples and climatic conditions under test;
• description of test set-up and instrument used for the test;
• number of samples;
• date of test;
• electrode system (tapered pin or bar electrodes);

• each single value and the median of the insulating resistance between tapered pin
electrodes or bar electrodes respectively;
• ambient conditions during testing;
• any other important observations, if applicable.
7 Repeatability and reproducibility
Measurements of insulation resistance are dependent on numerous aspects. Experiences
have shown that the reproducibility is in the range of >50 %. (of the measured value).
The repeatability is between 20 % and 50 %.

– 16 – IEC 62631-3-3:2015 © IEC 2015
Bibliography
[1] IEC 60050-121, International electrotechnical vocabulary – Part 121:
Electromagnetism
[2] IEC 62631-3-1, Dielectric and resistive properties of solid insulating materials – Part
3-1: Determination of resistive properties (DC methods) – Volume resistance and
volume resistivity
[3] IEC 62631-3-2, Dielectric and resistive properties of solid insulating materials – Part
3-2: Determination of resistive properties (DC methods) – Surface resistance and
surface resistivity
[4] EN 10088-2, Stainless steels – Part 2: Technical delivery conditions for sheet/plate
and strip of corrosion resisting steels for general purposes
[5] BRINGAS, John E., Handbook of comparative world steel standards, 4th ed.
ASTM data series DS67C. ISBN 978-0-8031-6223-5
[6] Stahlschlüssel-Taschenbuch 2013: Wissenswertes über Stähle, ISBN: 3922599281

___________
___________
To be published.
– 18 – IEC 62631-3-3:2015 © IEC 2015
SOMMAIRE
AVANT-PROPOS . 19
1 Domaine d'application . 21
2 Références normatives . 21
3 Termes et définitions . 21
4 Signification . 24
5 Méthode d’essai . 25
5.1 Généralités . 25
5.2 Conditions d’essai . 25
5.2.1 Tension . 25
5.2.2 Matériau des électrodes . 25
5.3 Appareillage . 26
5.3.1 Généralités . 26
5.3.2 Précision . 26
5.3.3 Source de tension . 26
5.4 Étalonnage . 26
5.5 Spécimens d'essai . 27
5.5.1 Dimensions des spécimens d'essai . 27
5.5.2 Spécimens d'essai pour la résistance d'isolement entre des électrodes
en forme de broches coniques . 27
5.5.3 Spécimens d'essai pour la résistance d'isolement entre des électrodes
en forme de barrettes . 27
5.5.4 Fabrication des spécimens d'essai. 27
5.5.5 Nombre de spécimens d'essai . 28
5.5.6 Conditionnement et prétraitement des spécimens d'essai . 28
5.6 Application d'électrodes . 28
5.6.1 Application d'électrodes en forme de broches coniques . 28
5.6.2 Application d'électrodes en forme de barrettes . 29
5.7 Procédure d'essai . 30
5.8 Evaluation . 30
5.8.1 Résistance d'isolement entre des électrodes en forme de broches
coniques . 30
5.8.2 Résistance d'isolement entre des électrodes en forme de barrettes . 30
6 Rapport d’essai . 30
7 Répétabilité et reproductibilité . 31
Bibliographie . 32

Figure 1 – Arrangements d'électrodes en forme de broches . 22
Figure 2 – Arrangement d'électrodes en forme de barrettes . 23

Tableau 1 – Composition de l'acier des électrodes . 26

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
PROPRIÉTÉS DIÉLECTRIQUES ET RÉSISTIVES
DES MATÉRIAUX ISOLANTS SOLIDES –

Partie 3-3: Détermination des propriétés résistives
(méthodes en courant continu) – Résistance d'isolement

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l’IEC). L’IEC a pour
objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines
de l'électricité et de l'électronique. A cet effet, l’IEC – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de l’IEC"). Leur élaboration est confiée à des
comités d'études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec l’IEC, participent
également aux travaux. L’IEC collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de l’IEC concernant les questions techniques représentent, dans la mesure
du possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de l’IEC
intéressés sont représentés dans chaque comité d’études.
3) Les Publications de l’IEC se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de l’IEC. Tous les efforts raisonnables sont entrepris afin que l’IEC
s'assure de l'exactitude du contenu technique de ses publications; l’IEC ne peut pas être tenue responsable de
l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
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mesure possible, à appliquer de façon transparente les Publications de l’IEC dans leurs publications nationales
et régionales. Toutes divergences entre toutes Publications de l’IEC et toutes publications nationales ou
régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) L’IEC elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d'évaluation de conformité et, dans certains secteurs, accèdent aux marques de
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6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
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mandataires, y compris ses experts particuliers et les membres de ses comités d'études et des Comités
nationaux de l’IEC, pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre
dommage de quelque nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais
de justice) et les dépenses découlant de la publication ou de l'utilisation de cette Publication de l’IEC ou de
toute autre Publication de l’IEC, ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de l’IEC peuvent faire
l’objet de droits de brevet. L’IEC ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits
de brevets et de ne pas avoir signalé leur existence.
La Norme internationale IEC 62631-3-3 a été établie par le comité d'études
...