IEC 62631-3-2:2015

IEC 62631-3-2 ®
Edition 1.0 2015-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dielectric and resistive properties of solid insulating materials –
Part 3-2: Determination of resistive properties (DC methods) – Surface
resistance and surface resistivity

Propriétés diélectriques et résistives des matériaux isolants solides –
Partie 3-2: Détermination des propriétés résistives (méthodes en courant
continu) – Résistance superficielle et résistivité superficielle

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IEC 62631-3-2 ®
Edition 1.0 2015-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dielectric and resistive properties of solid insulating materials –

Part 3-2: Determination of resistive properties (DC methods) – Surface

resistance and surface resistivity

Propriétés diélectriques et résistives des matériaux isolants solides –

Partie 3-2: Détermination des propriétés résistives (méthodes en courant

continu) – Résistance superficielle et résistivité superficielle

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.99; 29.035.01 ISBN 978-2-8322-3025-1

– 2 – IEC 62631-3-2:2015  IEC:2015
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Significance . 7
5 Method of test . 7
5.1 General . 7
5.2 Voltage . 8
5.3 Equipment . 8
5.3.1 General . 8
5.3.2 Accuracy . 8
5.3.3 Voltage source . 8
5.3.4 Electrode arrangement A – Spring loaded electrodes . 8
5.3.5 Electrode arrangement B – Small line electrodes . 9
5.3.6 Electrode arrangement C – Annular electrodes . 10
5.3.7 Electrode arrangement D – Line electrodes . 11
5.3.8 Electrode arrangement E – Line electrodes for small plates . 11
5.4 Test circuit . 11
5.5 Calibration . 12
5.6 Test specimen . 12
5.6.1 Recommended dimensions of test specimen and electrode
arrangements . 12
5.6.2 Manufacturing of test specimen . 12
5.6.3 Number of test specimen . 13
5.6.4 Application of electrodes. 13
5.6.5 Conditioning and pre-treatment of test specimen . 13
5.7 Test procedure . 13
6 Evaluation . 13
6.1 For electrode arrangements A, B, D, and E . 13
6.2 For electrode arrangement C . 14
7 Test report . 14
8 Repeatability and reproducibility . 15
Annex A (informative) Specimen dimensions and electrode arrangement . 16
Bibliography . 17

Figure 1 – Electrode arrangement A (example) . 9
Figure 2 – Collector electrode for electrode arrangement B. 10
Figure 3 – Electrode arrangement C . 10
Figure 4 – Connection diagram of measurement with two- and three-terminal electrode
arrangements. 12

Table 1 – Typical electrode dimensions for electrode arrangement C . 11
Table A.1 – Recommended test specimen dimensions and electrode arrangements for
specific products . 16

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

Part 3-2: Determination of resistive properties (DC methods) –
Surface resistance and surface resistivity

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 62631-3-2 has been prepared by IEC technical committee 112:
Evaluation and qualification of electrical insulating materials and systems.
This first edition cancels and replaces the second edition of IEC 60093, published in 1980,
and constitutes a technical revision.
This edition includes the following significant technical changes with respect to the second
edition of IEC 60093:
a) IEC 60093 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;
c) volume and surface resistance and resistivity are now separated into IEC 62631-3-1 and
IEC 62631-3-2, respectively.
– 4 – IEC 62631-3-2:2015  IEC:2015
The text of this standard is based on the following documents:
FDIS Report on voting
112/340FDIS 112/351/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 3-2: Determination of resistive properties (DC methods) –
Surface resistance and surface resistivity

1 Scope
This part of IEC 62631 covers methods of test for the determination of surface resistance and
surface resistivity of electrical insulation materials 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 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 – General method
IEC 62631-3-3, Dielectric and resistive properties of solid insulating materials – Part 3-3:
Determination of resistive properties (DC Methods) – Insulation resistance
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
electrode arrangement
electrical conductive bodies on the surface of a test specimen
Note 1 to entry: The arrangement of electrodes should include procedures to ascertain sufficient contact to the
surface (e.g. by means of conducting paint) and/or the use of an adequate mechanical system applying the
necessary contact force to the test specimen’s surface.
3.1.1
spring loaded electrodes
line electrode system using two parallel lines of conducting spring tongues with sharp edges,
separated by a gap
3.1.2
line electrodes
electrode arrangement provided by two parallel lines, separated by a gap, applied to the test
specimen’s surface using a conductive material
___________
To be published.
– 6 – IEC 62631-3-2:2015  IEC:2015
3.1.3
annular electrodes
central circular planar electrode with a surrounding ring electrode separated by a gap
Note 1 to entry: Guarded electrode systems as described in IEC 62631-3-1 are of similar shape. In the case of
surface resistance, the ring electrode does not have the function of a guard; guard functionality, however, is
provided by the opposite electrode.
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 three terminal electrode arrangement may be used to exclude undesired volume currents from
the determination of the measured resistance.
Note 2 to entry: A Wheatstone bridge may also be used to compare the measured resistance with a standard
resistor. However, Wheatstone bridges are not commonly used anymore.
Note 3 to entry: According to IEC 60050-121: 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 surface
resistivity is an average of the resistivity over possible heterogeneities in the volume incorporated in the
measurement; it includes the effect of possible polarization phenomena at the electrodes.
3.3
surface resistance
R
S
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 , R , R , R or R with
SA SB SC SD SE
surface resistance, R expressed by the unit Ω.
S
Note 2 to entry: An indeterminable part of the resistance inside the material is also included in surface resistance
during measurement of this resistance.
3.4
surface resistance between spring loaded electrodes
R
SA
measured resistance between spring loaded electrodes
3.5
surface resistance between small line electrodes
R
SB
measured resistance between small line electrodes
3.6
surface resistance between annular electrodes
R
SC
measured resistance between the inner circular area of an annular electrode system and the
outer circular ring electrode.
3.7
surface resistance between line electrodes
R
SD
measured resistance between line electrodes
3.8
surface resistance between line electrodes for small plates
R
SE
measured resistance between line electrodes for small plates

3.9
surface resistivity
σ
surface resistance R , R , R R or R referred to a square, expressed as σ , σ , σ , σ
SA SB SC, SD SE A B C D
and σ respectively
E
Note 1 to entry: Surface resistivity σ , σ and σ is expressed by the unit Ω.
C D E
Note 2 to entry: Surface resistivity is often also expressed by the non-standardized unit Ω per square, to show
that the electrode dimension has been taken into account by calculating the specific value.
Note 3 to entry: It can be compared for materials only if identical dimensions of the electrodes are used.
Recommended dimensions are given in 5.3.
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.
Surface resistance is, as volume resistance, a part of the insulating resistance.
Insulating resistance shall be determined according to IEC 62631-3-3 and volume resistance
according to IEC 62631-3-1.
Surface resistance supplies information on the electrical resistances on the surface of
materials and products. The surface resistance also permits monitoring of changes in the
resistance by external effects. Surface resistance, however, for its major part is not a material
property. Surface resistance depends mainly on processing parameters, environmental
conditions, surface ageing phenomena and pollution, etc.
Dependent on the specific application, different electrode arrangements can be preferable.
5 Method of test
5.1 General
This general method describes common values for general measurements. If a method for a
specific type of material is described in this standard, the specific method shall be used.
Different types of electrodes can be used, dependent on the specific measurement or product
demands. For instance, on surfaces with a curved shape, a small line electrode can be
advantageous. Spring loaded electrodes provide measurements with low effort on products
and are optimal for materials which have to be conditioned before the test. If not already
stipulated by a product standard, the choice of the electrode arrangement shall be made
considering the typical application.
If test specimen are made from materials (e.g. soft rubber) changing their dimensions
significantly when applying force by electrodes on them, these electrodes are not applicable
and an alternative arrangement shall be used.
If no information about the application is available, small line electrodes (R ) are
SB
recommended.
– 8 – IEC 62631-3-2:2015  IEC:2015
5.2 Voltage
The measuring voltage shall preferably be
10 V, 100 V, 500 V, 1 000 V and 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.
5.3 Equipment
5.3.1 General
Care should be taken that the surface 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.
For the determination of surface resistance and surface resistivity different electrode
arrangements can be used. The evaluation of surface resistivity is dependent on the selected
electrode arrangement.
5.3.2 Accuracy
Any suitable equipment can be used. The measuring device shall be capable of determining
the unknown resistance with an overall accuracy of at least
Ω,
• ±10 % for resistances below 10
10 14
• ±20 % for resistances 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.
5.3.4 Electrode arrangement A – Spring loaded electrodes
The electrode arrangement A shall consist of two flexible metal knife-edges with a length of
100 mm and a gap distance of 10 mm apart as shown in Figure 1.
No guard electrode is used. The metal knife-edges shall consist of individual spring tongues
arranged next to each other about 0,3 mm apart and each with a length not exceeding 5 mm
and 0,3 mm thick. The contact force shall be high enough so that all tongues or segments rest
against the surface of the test specimen, but without damaging the surface.
A piece of metal exerting the contact force should be applied with high-grade insulation where
in contact with the specimen.
1 2 3 1
10±0,1
IEC
Key
1 guide bar (detachable)
2 metal knife-edges
3 specimen
Figure 1 – Electrode arrangement A (example)
5.3.5 Electrode arrangement B – Small line electrodes
Electrode arrangement B shall consist of two adhering line electrodes. No guard electrode is
used. For this purpose, two 1,5 mm wide lines with a length of 25 mm and a gap distance of
2 mm apart shall be applied, e.g. with conductive silver. They shall be applied before the
conditioning. The lines shall be contacted using a two terminal collector electrode
arrangement with conductive blades in attach to them (see Figure 2).
2 10
100±0,5
– 10 – IEC 62631-3-2:2015  IEC:2015

IEC
Figure 2 – Collector electrode for electrode arrangement B
5.3.6 Electrode arrangement C – Annular electrodes
Electrode arrangement C is a three terminal electrode system, as shown in Figure 3. On one
side of the test specimen, annular electrodes are applied. The opposite surface of the test
specimen is to be covered by a guard electrode, not smaller than the area covered by the
corresponding electrodes. Adhesive electrodes can be applied before the conditioning (see
5.6.3).
Key
1 specimen
2 electrode 1
3 measuring area
4 electrode 2
5 electrode 3 (guard electrode)

d
d
d
m
d
IEC
Figure 3 – Electrode arrangement C
Any electrode dimension can be used, unless otherwise stipulated. Typical electrode
dimensions are given by Table 1. For comparison tests, electrode arrangement C1 is
recommended.
a
Table 1 – Typical electrode dimensions for electrode arrangement C
d in mm d in mm d in mm
1 2 3
C1 50 60 80
C2 76 88 100
C3 25 38 50
With electrode arrangement C, the surface resistance between electrode 1 and electrode 2
shall be measured. Electrode 3 shall be earthed.
In the case of materials with limited conductivity and also occasionally with films ≤ 10 µm, it
shall be noted that the input resistance of the ammeter is significantly smaller than the volume
resistance of the test specimen.
5.3.7 Electrode arrangement D – Line electrodes
Electrode arrangement D shall consist of two adhering line electrodes. No guard electrode is
used. The electrode dimensions are correspondent to electrode arrangement A with regard to
the electrode length and distance between electrodes. No guard electrode is used.
For this purpose, two parallel 1,5 mm wide lines with a length of (100 ± 1) mm and a gap
distance of (10 ± 0,5) mm apart shall be applied, e.g. with conductive silver. They can be
applied before the treatment. The lines shall be contacted using a two terminal collector
electrode arrangement with conductive blades attached to them (see Figure 2).
5.3.8 Electrode arrangement E – Line electrodes for small plates
Electrode arrangement E is a three terminal line electrode system. For this purpose, two
parallel 1 mm to 2 mm wide lines with a length of (50 ± 1) mm and a gap distance of
(5 ± 0,5) mm apart shall be applied, e.g. with conductive silver.
The opposite surface of the test specimen is to be covered by a guard electrode not smaller
than the area covered by the corresponding electrodes. The electrodes can be applied before
conditioning of the test specimen. The lines shall be contacted using a three terminal collector
electrode arrangement (see Figure 4b).
NOTE Electrode arrangement E is preferable when small plates (≥ 60 mm × ≥ 60 mm) according to ISO 10350 are
in use.
5.4 Test circuit
Dependent on the electrode arrangement selected, two- or three-terminal measurements shall
be carried out (see Figure 4).
For annular electrodes (electrode arrangement C) and line electrode arrangement E a three-
terminal test circuit is necessary as a grounded protective electrode is mandatory.
For any other line electrode arrangement (A, B and D), a two-terminal test circuit shall be
used.
– 12 – IEC 62631-3-2:2015  IEC:2015
g
d
f
e
2 g
d
e
A) Guarded annular 2
a b c
electrode
g
V A
C) Unprotected line
electrode
d
f
e
B) Protected line
electrode
IEC
Key
a) voltage source
b) voltmeter
c) ammeter
d) electrode 1
e) electrode 2 (shielded electrode)
f) electrode 3 (protective electrode)
g) specimen
Figure 4 – Connection diagram of measurement with
two- and three-terminal electrode arrangements
5.5 Calibration
The equipment shall be calibrated in the magnitude of the surface resistance measured.
NOTE Calibration resistors in a range of up to 100 TΩ are commercially available.
5.6 Test specimen
5.6.1 Recommended dimensions of test specimen and electrode arrangements
The specimen’s dimensions need be sufficient to apply the selected electrode arrangement.
Recommendations for products are given in Annex A.
5.6.2 Manufacturing of test specimen
The 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.).
Specimen from products shall be prepared with the product thickness, if possible.
5.6.3 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.
5.6.4 Application of electrodes
When using adhesive electrodes (electrode arrangements B, C, D and E), care shall be taken,
that a proper contact is provided over the whole area covered by the electrode. The electrode
material used shall – after an appropriate time of conditioning – not influence the measured
values for surface resistance.
NOTE Conductive silver paint and suspensions of graphite have been found appropriate.
5.6.5 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).
If not otherwise stipulated, no cleaning of the test specimen shall be done. Any additional
contamination shall be avoided.
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).
The specimen shall be conditioned and pre-treated according to 5.6.5. Immediately after the
treatment, the electrodes shall be connected with the measuring device.
Subsequently, but no more than 2 min after finishing the conditioning or pre-treatment, the
shall be determined between the electrodes. If not otherwise stipulated,
surface resistance R
S
it shall be measured 1 min after voltage application.
6 Evaluation
6.1 For electrode arrangements A, B, D, and E
for the respective surface resistance R , R , R and R between
The measured value R
S SA SB SD SE
electrodes 1 and 2 shall be specified in Ω.
For electrode arrangements A, B, D and E, surface resistivity σ can be calculated in Ω
according to Equation (1) from the measured resistance R and electrode dimensions.
S
It is also possible to calculate surface resistivity even with dimensions deviating from those
defined in 5.3.4, 5.3.5, 5.3.7 and 5.3.8.

– 14 – IEC 62631-3-2:2015  IEC:2015
l
σ = ⋅ R (1)
SY
Y
g
where
l is the length of line electrodes
g is the distance between the lines (gap)
and
Y reading A, B, D or E.
As the individual surface resistances are dependent on the electrode and are therefore not
comparable with each other, the type of electrode arrangement shall be specified with the
measured value to permit a statement.
6.2 For electrode arrangement C
The surface resistance R between electrodes 1 and 2 with earthed electrode 3 shall be
SC
specified in Ω.
The surface resistivity σ can be calculated in Ω according to Equation (2) from the measured
C
resistance R and electrode dimensions (see Figure 3).
SC
d + d
2 1
σ = ⋅π ⋅ R (2)
C SC
d − d
2 1
where
d is the outer diameter of the inner electrode
d is the inner diameter of the ring electrode
7 Test report
The report shall include the following:
• electrode arrangement and electrode dimensions;
• complete identification and description of the material tested, including source and
manufacturer’s code;
• shape and thickness of test specimen;
• test voltage;
• accuracy of the instrument and calibration method, depending on the measured values of
resistance, if necessary;
• 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;
• each single value and the median of surface resistance and surface resistivity,
respectively;
• ambient conditions during testing;
• any other important observations if applicable.

8 Repeatability and reproducibility
Measurements of surface resistance and surface resistivity 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 62631-3-2:2015  IEC:2015
Annex A
(informative)
Specimen dimensions and electrode arrangement
Specimen dimensions and electrode arrangement are given in Table A.1.
For materials which are not available in flat sheets the electrode arrangement should be
agreed between supplier and customer.
Table A.1 – Recommended test specimen dimensions
and electrode arrangements for specific products
Type of product Recommended Remarks Recommended
electrode dimensions of test
arrangement specimen
Thermoplastic moulding E, C See ISO 10350-1
≥ 60 mm × ≥ 60 mm
compounds
Thermosetting moulding A, E, C See ISO 14526,
≥ 60 mm × ≥ 60 mm
compounds ISO 14527, ISO 14528,
≥100 mm × ≥ 100 mm
ISO 14529, ISO 14530,
ISO 15252
Long fibre, reinforced A, C EN 14598
≥100 mm × ≥ 100 mm
polyester and vinyl ester
ISO 10350-2
moulding compounds
(SMC BMC)
Epoxy based sheets and A, C IEC 60893-2
laminates
Pipes, bars and rods B, D IEC 61212-2
IEC 62011-2
Elastomeric materials B
Bibliography
IEC 60050-121, International Electrotechnical Vocabulary – Part 121: Electromagnetism
IEC 60893-2, Industrial rigid laminated sheets based on thermosetting resins for electrical
purposes – Part 2: Methods of test
IEC 61212-2, Insulating materials - Industrial rigid round laminated tubes and rods based on
thermosetting resins for electrical purposes – Part 2: Methods of test
IEC 62011-2, Insulating materials - Industrial, rigid, moulded, laminated tubes and rods of
rectangular and hexagonal cross-section, based on thermosetting resins for electrical
purposes – Part 2: Methods of test
ISO 10350 (all parts), Plastics – Acquisition and presentation of comparable single-point data
ISO 10350-1, Plastics – Acquisition and presentation of comparable single-point data –
Part 1: Moulding materials
ISO 10350-2, Plastics – Acquisition and presentation of comparable single-point data –
Part 2: Long-fibre-reinforced plastics
ISO 14526 (all parts), Plastics – Phenolic powder moulding compounds (PF-PMCs)
ISO 14527 (all parts), Plastics – Urea-formaldehyde and urea/melamine-formaldehyde powder
moulding compounds (UF- and UF/MF-PMCs)
ISO 14528 (all parts), Plastics – Melamine-formaldehyde powder moulding compounds (MF-
PMCs)
ISO 14529 (all parts), Plastics – Melamine/phenolic powder moulding compounds (MP-PMCs)
ISO 14530 (all parts), Plastics – Unsaturated-polyester powder moulding compounds (UP-
PMCs)
ISO 15252 (all parts), Plastics – Epoxy powder moulding compounds (EP-PMCs)
EN 14598 (all parts), Reinforced thermosetting moulding compounds – Specification for Sheet
Moulding Compound (SMC) and Bulk Moulding Compound (BMC)

____________
– 18 – IEC 62631-3-2:2015  IEC:2015
SOMMAIRE
AVANT-PROPOS . 19
1 Domaine d'application . 21
2 Références normatives . 21
3 Termes et définitions . 21
4 Signification . 23
5 Méthode d’essai . 23
5.1 Généralités . 23
5.2 Tension . 24
5.3 Appareillage . 24
5.3.1 Généralités . 24
5.3.2 Précision . 24
5.3.3 Source de tension . 24
5.3.4 Arrangement d'électrodes A – Electrodes à ressort . 25
5.3.5 Arrangement d'électrodes B – Electrodes en forme de petites lignes . 26
5.3.6 Arrangement d'électrodes C – Electrodes annulaires . 26
5.3.7 Arrangement d'électrodes D – Electrodes en forme de lignes . 27
5.3.8 Arrangement d'électrodes E – Electrodes en forme de lignes pour
petites plaques . 28
5.4 Circuit d'essai . 28
5.5 Étalonnage . 29
5.6 Spécimens d'essai . 29
5.6.1 Dimensions recommandées pour les spécimens d'essai et les
arrangements d'électrodes . 29
5.6.2 Fabrication des spécimens d'essai. 29
5.6.3 Nombre de spécimens d'essai . 30
5.6.4 Application d'électrodes . 30
5.6.5 Conditionnement et prétraitement des spécimens d'essai . 30
5.7 Procédure d'essai . 30
6 Evaluation . 30
6.1 Pour les arrangements d'électrodes A, B, D et E . 30
6.2 Pour l'arrangement d'électrodes C . 31
7 Rapport d’essai . 31
8 Répétabilité et reproductibilité . 32
Annexe A (informative) Dimensions des spécimens et arrangement d'électrodes . 33
Bibliographie . 34

Figure 1 – Arrangement d'électrode A (exemple) . 25
Figure 2 – Electrode collectrice pour l'arrangement d'électrodes B . 26
Figure 3 – Arrangement d'électrodes C . 27
Figure 4 – Schéma de co
...