IEC 62788-1-7:2020

Measurement procedures for materials used in photovoltaic modules - Part 1-7: Encapsulants - Test procedure of optical durability

IEC 62788-1-7:2020 is designed as a more rigorous qualification test, using accelerated UV exposure at elevated temperature to determine whether polymeric encapsulants can suffer loss of optical transmittance. IEC 61215-2 already includes a UV preconditioning test (MQT 10), however, the parameters for that test only represent a limited level of exposure (~weeks of UV dose). This test procedure is intended for representative coupon specimens, applying stress at a greater intensity (designed relative to Phoenix, AZ), using a radiation spectrum that is more similar to the terrestrial solar spectrum, and using a duration of exposure that is more relevant to the PV application (i.e., equivalent to several years of outdoor exposure). This test quantifies the degradation rate of encapsulants so that the risk of the materials losing optical transmittance during operation in the terrestrial environments can be managed. The quantitative correlation between climate (or location of use), a specific application (utility installation, residential-installation, roof-mount, rack-mount, use of a tracker, the system electrical configuration and its operation), and the test can be established for each specific encapsulant material, but is beyond the scope of this document.

Procédures de mesure des matériaux utilisés dans les modules photovoltaïques - Part 1-7: Encapsulants - Procédure d’essai de la durabilité optique

l’IEC 62788-1-7:2020 est conçue comme un essai de qualification plus rigoureux, qui utilise une exposition aux UV accélérée à température élevée destinée à déterminer si les encapsulants polymérisés peuvent présenter une perte de facteur de transmission optique. L’IEC 61215-2 comprend déjà un essai de préconditionnement aux UV (MQT 10), toutefois, les paramètres de cet essai ne représentent qu’un niveau limité d’exposition (~semaines de dose d’UV). La présente procédure d'essai concerne les éprouvettes de coupon représentatives et applique des contraintes d’une plus grande intensité (conçues par rapport à Phoenix, AZ), en utilisant un spectre de rayonnement qui est plus proche du spectre lumineux solaire terrestre et une durée d'exposition plus pertinente pour l’application PV (c’est à dire équivalente à plusieurs années d'exposition en extérieur). Cet essai quantifie la vitesse de dégradation des encapsulants de manière à pouvoir gérer le risque de perte de facteur de transmission optique des matériaux au cours du fonctionnement dans l’environnement terrestre. La corrélation quantitative entre le climat (ou le lieu d'utilisation), une application spécifique (installation de service public, installation résidentielle, montage sur toit, montage sur châssis, utilisation d'un traqueur, configuration électrique du système et son fonctionnement) et l’essai peut être établie pour chaque matériau d’encapsulation spécifique mais n’entre pas dans le domaine d’application du présent document.

General Information

• Status: Published
• Publication Date: 20-Apr-2020
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: WG 2 - TC 82/WG 2
• Current Stage: PPUB - Publication issued
• Start Date: 21-Apr-2020
• Completion Date: 17-Apr-2020

Standards Content (Sample)

IEC 62788-1-7 ®
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Measurement procedures for materials used in photovoltaic modules –
Part 1-7: Encapsulants – Test procedure of optical durability

Procédures de mesure des matériaux utilisés dans les modules
photovoltaïques –
Partie 1-7: Encapsulants – Procédure d’essai de la durabilité optique

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IEC 62788-1-7 ®
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Measurement procedures for materials used in photovoltaic modules –

Part 1-7: Encapsulants – Test procedure of optical durability

Procédures de mesure des matériaux utilisés dans les modules

photovoltaïques –
Partie 1-7: Encapsulants – Procédure d’essai de la durabilité optique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-8035-5

– 2 – IEC 62788-1-7:2020 © IEC 2020
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Principle . 7
5 Apparatus . 7
5.1 Spectrophotometer for transmittance measurements . 7
5.2 Environmental chamber for weathering . 7
6 Test specimens . 8
6.1 Specimen components and general considerations for all material types . 8
6.2 Test specimens for datasheet reporting . 8
6.3 Use of alternate superstrate and substrate materials . 8
6.4 Witness specimens and experimental control . 9
7 Measurement procedure . 9
8 Artificial accelerated weathering . 9
9 Calculation and expression of results . 9
10 Test procedure . 10
11 Pass/fail criteria . 10
12 Test report . 11
Bibliography . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEASUREMENT PROCEDURES FOR
MATERIALS USED IN PHOTOVOLTAIC MODULES –

Part 1-7: Encapsulants –
Test procedure of optical durability

FOREWORD
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International Standard IEC 62788-1-7 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
The text of this International Standard is based on the following documents:
FDIS Report on voting
82/1669/FDIS 82/1704/RVD
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62788 series, published under the general title Measurement
procedures for materials used in photovoltaic modules, can be found on the IEC website.

– 4 – IEC 62788-1-7:2020 © IEC 2020
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://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
IEC 61215-2 (covering module design qualification and type approval) specifies a UV
-2 -2
preconditioning of 54 MJ⋅m (15 kWh⋅m ), which would be encountered after ~40 ideal sunny
days of exposure to the AM1.5G UV spectrum in IEC 60904-3. IEC 61730-2 presently specifies
4x the same UV exposure, i.e., 5 months UV dose. The International PV Quality Assurance
Task Force (PVQAT) leads global efforts to craft quality and reliability standards for solar
energy technologies. These standards will allow stakeholders to quickly assess a solar
photovoltaic (PV) module's performance and ability to withstand weather stresses, thereby
reducing risk and adding confidence for those developing products, designing incentive
programs, and determining private investments. As developed in conjunction with PVQAT, this
part of IEC 62788-1 is intended to supplement module qualification, which typically covers
reliability issues related to infant mortality, i.e., the first months of field use. This part of
IEC 62788-1 may also facilitate the pre-qualification of encapsulation materials using coupon
specimens, because long term weathering is not practical for larger module specimens. This
part of IEC 62788-1 also importantly uses high fidelity UV irradiation (relative to the terrestrial
solar spectrum), which is not practical to apply to module specimens (due to the lack of available
commercial equipment and the anticipated cost of operation).This part of IEC 62788-1 is not
presently specified for pre-qualification purposes in other standards, but may be used for that
purpose by module manufacturers.
The optical performance (transmittance) of polymeric frontsheets and backsheets is not covered
in this part of IEC 62788-1. These components are addressed in the IEC TS 62788-2.

– 6 – IEC 62788-1-7:2020 © IEC 2020
MEASUREMENT PROCEDURES FOR
MATERIALS USED IN PHOTOVOLTAIC MODULES –

Part 1-7: Encapsulants –
Test procedure of optical durability

1 Scope
IEC 61215-2 provides a set of qualification tests that indicate that a PV module design is likely
to be free of flaws that will result in early failure. However, IEC 61215-2 does not address the
long term wear-out of PV modules. This part of IEC 62788-1 is designed as a more rigorous
qualification test, using accelerated UV exposure at elevated temperature to determine whether
polymeric encapsulants can suffer loss of optical transmittance. IEC 61215-2 already includes
a UV preconditioning test (MQT 10), however, the parameters for that test only represent a
limited level of exposure (~weeks of UV dose). This test procedure is intended for
representative coupon specimens, applying stress at a greater intensity (designed relative to
Phoenix, AZ), using a radiation spectrum that is more similar to the terrestrial solar spectrum,
and using a duration of exposure that is more relevant to the PV application (i.e., equivalent to
several years of outdoor exposure). This test quantifies the degradation rate of encapsulants
so that the risk of the materials losing optical transmittance during operation in the terrestrial
environments can be managed. The quantitative correlation between climate (or location of use),
a specific application (utility-installation, residential-installation, roof-mount, rack-mount, use of
a tracker, the system electrical configuration and its operation), and the test can be established
for each specific encapsulant material, but is beyond the scope of this document.
The method herein is intended to qualify encapsulants for use in a PV module. This document
is intended to apply to encapsulants used in PV modules deployed under temperature
conditions of normal use, as defined in IEC TS 63126. The use of this method for encapsulants
in modules deployed under conditions of higher temperature is specified elsewhere, for example
IEC TS 63126. The method here is intended to be used to examine a particular encapsulant
and does not cover incompatibilities between the encapsulant and other packaging materials.
This document covers PV technology constructed using a transparent incident
surface/encapsulant/photovoltaic device construction, the relevance to other geometries where
the encapsulant layer is located behind the photovoltaic device layer, is outside the scope of
this document. In the case of bifacial cell technology, the module can accept light from its front
and back surfaces – the transmittance of a frontsheet (if used), encapsulant, and transparent
backsheet (if used) is relevant for both active surfaces. The optical durability of frontsheets and
backsheets, however, is addressed separately in the IEC TS 62788-2. Thin coatings that might
be added for antireflection or anti-soiling purposes are outside the scope of this document. The
method in this document can be used for other purposes (e.g., research and development);
many details of alternate uses of the method (e.g., alternate test durations or measurement
increments) are not described here.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61215-2, Terrestrial photovoltaic (PV) modules – Design qualification and type approval –
Part 2: Test procedures
IEC 61730-1, Photovoltaic (PV) module safety qualification – Part 1: Requirements for
construction
IEC TS 61836, Solar photovoltaic energy systems – Terms, definitions and symbols
IEC 62788-1-4, Measurement procedures for materials used in photovoltaic modules. Part 1-4:
Encapsulants – Measurement of optical transmittance and calculation of the solar-weighted
photon transmittance, yellowness index, and UV cut-off wavelength
IEC TS 62788-7-2, Measurement procedures for materials used in photovoltaic modules –
Part 7-2: Environmental exposures – Accelerated weathering tests of polymeric materials
IEC TS 62915, Photovoltaic (PV) modules – Type approval, design and safety qualification –
Retesting
IEC TS 63126 , Guidelines for qualifying PV modules, components, and materials for operation
at high temperatures
ISO 291, Plastics – Standard atmospheres for conditioning and testing
ASTM G7, Standard practice for atmospheric environmental exposure testing of nonmetallic
materials
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC TS 61836 and
IEC 61730-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Principle
The total spectral transmittance shall be quantified using a spectrophotometer equipped with
an integrating sphere (IEC 62788-1-4). Artificial weathering shall be performed at stable
specified irradiance, temperature, and relative humidity conditions using an environmental
chamber (IEC TS 62788-7-2). The changes in transmittance resulting from weathering shall be
quantified using subsequent spectrophotometer measurement(s). The results of this artificial
weathering test may be benchmarked against natural weathering, for example ASTM G7.
5 Apparatus
5.1 Spectrophotometer for transmittance measurements
A double beam or single beam spectrophotometer equipped with an integrating sphere and
conforming to the requirements of IEC 62788-1-4 shall be used.
5.2 Environmental chamber for weathering
An artificial weathering apparatus shall be used, as specified in IEC TS 62788-7-2. The
weathering apparatus shall meet the requirements of the artificial accelerated weathering
method specified, for example IEC TS 62788-7-2, method A3.
___________
Under preparation. Stage at the time of publication: IEC/DTS 63126:2019.

– 8 – IEC 62788-1-7:2020 © IEC 2020
6 Test specimens
6.1 Specimen components and general considerations for all material types
Specimens shall be constructed according to the geometry, methodology, and number of
replicates for weathering test specimens as specified in IEC 62788-1-4.
Silica glass shall be used for the encapsulant specimens to standardize the results for the
purpose of datasheet reporting of the durability. Silica glass may be used to achieve the worst-
case weathering results, i.e., the most accelerated, because it is fully UV transmitting. The silica
shall fulfill the requirements of IEC 62788-1-4.
To limit the propagation of localized weathering damage through the specimens, the indicated
specimens should be marked (with a serial number or other identifier) on the side that is not
facing the incident radiation. Because of the aggressive nature of the combined stress factors
applied during artificial weathering, it is recommended to mark by physically scribing the
substrate.
All specimens shall be laminated or processed in a manner similar to that used to fabricate PV
modules.
6.2 Test specimens for datasheet reporting
Encapsulant specimens shall consist of glass/encapsulant/glass coupons as specified in
IEC 62788-1-4.
Some module geometries are constructed using separate front encapsulant (that is UV
transparent) and back encapsulant (that is not UV transparent). The durability of each
encapsulant material shall be examined separately using separate coupons containing each
specific material.
6.3 Use of alternate superstrate and substrate materials
For the purpose of research and development, other materials including photovoltaic glass and
UV attenuating encapsulant may be used in coupon specimens. The test may reveal material
specific degradation, particularly when product glass and/or encapsulants are used.
Photovoltaic glass may be used to achieve weathering that is more representative of that
encountered in a PV module. Photovoltaic glass, however, shall not be used for the purpose of
datasheet reporting. If a superstrate glass other than silica is used, its transmittance should be
similar to the manufactured superstrate. In the case of module representative specimens, the
glass used in weathering shall have a solar weighted transmittance that is equal to or greater
than that of the glass used in PV modules between the UV cut-off wavelength and 400 nm. The
representative glass used in weathering shall also have an initial UV cut-off wavelength within
±2,5 nm that of the glass in used in PV modules, for example the same glass from the same
manufacturer. If the manufacturer’s tolerances for UV cut-off wavelength and solar weighted
transmittance are available for fabricated lots of photovoltaic glass used for test specimens,
then those should be used in place of the aforementioned limits.
In the case of modules using a polymeric frontsheet or superstrate that is not composed of
glass, that superstrate material may be used in the encapsulant coupons for weathering in the
place of glass. It is recommended to verify that the solar weighted transmittance of the
superstrate is equal to or greater than that of the superstrate used in PV modules between the
UV cut-off wavelength and 400 nm. The superstrate used in weathering shall also have an initial
UV cut-off wavelength within ±2,5 nm the superstrate used in PV modules, for example the
same superstrate material from the same manufacturer. If the manufacturer’s tolerances for UV
cut-off wavelength and solar weighted transmittance are available for fabricated lots of
superstrate material used for specimens, then those should be used in place of the
aforementioned limits.
Because the optical characteristics of a glass or a polymeric superstrate can be affected by
weathering (e.g., solarization of glass [1] or discoloration of polymeric materials), it is
suggested to include reference specimens of the glass or superstrate material for weathering,
if the stability of the superstrate material is unknown. For superstrate or substrate materials
that are known to solarize, it is suggested to artificially solarize those materials before
constructing test specimens.
6.4 Witness specimens and experimental control
Measurement of witness specimens, as described in IEC 62788-1-4, shall be used to verify the
measurements within each measurement session. Control measurements shall be performed
at the start and end of each measurement session. Control measurements may also be
performed intermediately, during the measurement session. The control measurements should
be compared to quantify and correct for drift of the spectrophotometer through the weathering.
7 Measurement procedure
Transmittance measurements shall be performed as specified in IEC 62788-1-4, including the
equilibration of the spectrophotometer lamp(s), baselining of the instrument, and use of witness
specimen(s). Specimens with an impermeable superstrate (e.g., glass) shall be conditioned
prior to optical measurements as specified in ISO 291 class 2, for example (23 ± 2) °C, (50 ±
10) % RH for at least 15 min to allow thermal equilibration. Specimens with a permeable
superstrate (e.g., polymeric frontsheet) shall be conditioned prior to optical measurements as
specified in ISO 291 class 2, for example (23 ± 2) °C, (50 ± 10) % RH for at least 24 h to
facilitate moisture equilibration. Because the transmittance at short wavelengths may be used
to diagnose the effects of weathering, it is recommended to measure the transmittance from
200 nm to 2 500 nm.
8 Artificial accelerated weathering
For encapsulants used in PV modules deployed under temperature conditions of normal use,
artificial accelerated weathering shall be performed in conformance with IEC TS 62788-7-2,
method A3. For encapsulants in modules deployed under conditions of higher temperature,
weathering shall be performed according to IEC TS 63126.
NOTE The details of the test conditions in IEC TS 62788-7-2, including: irradiance; chamber air temperature; black
panel temperature; and chamber relative humidity, are specified for reference here as IEC 62788-1-7 is developed.
Details including the intent of the test conditions are also provided here to facilitate the development of IEC 62788-
1-7. All of these details, however, will be removed in the final version of IEC 62788-1-7 because having them solely
located in IEC TS 62788-7-2 will prevent confusion as both documents are revised in the future.
-2 -1
IEC TS 62788-7-2, method A3: irradiance of 0,8 W⋅m ⋅nm , controlled at 340 nm; 65 °C
chamber air temperature with a 90 °C black panel temperature; and chamber relative humidity
of 20 %.
Specimens shall be conditioned prior to weathering as specified in IEC TS 62788-7-2.
9 Calculation and expression of results
Results and their corresponding uncertainty shall be calculated from the transmittance
measurements, including the solar-weighted transmittance, representative solar-weighted
transmittance (solar-weighted transmittance of photon irradiance transmitted throughout the
range of the spectrum utilized by a representative PV device, as defined in IEC 62788-1-4),
yellowness index, and UV cut-off wavelength, as specified in IEC 62788-1-4. The initial values
___________
Numbers in square brackets refer to the Bibliography.

– 10 – IEC 62788-1-7:2020 © IEC 2020
for the characteristics and the change in their performance following UV weathering shall be
reported.
10 Test procedure
The following test sequence shall be applied:
a) Specimen fabrication and preparation (as in IEC 62788-1-4).
b) Visual inspection (IEC 61215-2, MQT 01).
c) Specimen conditioning for measurement (as in IEC 62788-1-4 or ISO 291 class 2).
d) Initial transmittance measurement of the specimens (as in IEC 62788-1-4).
e) Transmittance measurement of the superstrate material coupon (as in IEC 62788-1-4).
At least one measurement shall be made on one coupon to verify the optical performance of
the superstrate material. The requirements of silica used for datasheet reporting are specified
in IEC 62788-1-4. For alternate materials used for alternate purposes, the performance of the
superstrate material may also be measured after weathering is complete.
f) Specimen conditioning for weathering (as in IEC TS 62788-7-2, if applicable).
g) Weathering (as in IEC TS 62788-7-2) including up to 2 000 cumulative hours.
h) Specimen conditioning for measurement (as in IEC 62788-1-4 or ISO 291 class 2).
i) Transmittance measurement of weathered specimens (as in IEC 62788-1-4).
j) Visual inspection (IEC 61215-2, MQT 01).
k) Weathering (as in IEC TS 62788-7-2) including up to 4 000 cumulative hours.
l) Specimen conditioning for measurement (as in IEC 62788-1-4 or ISO 291 class 2).
m) Transmittance measurement of weathered specimens (as in IEC 62788-1-4).
n) Visual inspection (IEC 61215-2, MQT 01).
o) Analysis and reporting of results (as in IEC 62788-1-4).
For datasheet reporting or qualification, weathering shall be performed for 2 000 and 4 000
cumulative hours. This weathering may be performed continuously or in multiple intermittent
weathering intervals up to the cumulative duration of 4 000 h.
11 Pass/fail criteria
The encapsulant fulfills the requirements of this document when each test sample meets all the
following criteria:
a) the change in the representative solar photon weighted transmittance does not exceed 5 %;
b) no evidence of major defects are observed after visual inspection in accordance with
MQT 01 in IEC 61215-2. Major defects include, but are not limited to, delamination or other
applicable defects, as defined in the visual inspection test. The size of major defects may
not exceed 5,2 mm.
If any of the test specimens do not meet these test criteria, the material shall be deemed not to
have met the requirements of this document.
A test report shall be issued by the test lab to the material manufacturer. The test report shall
document the results of the test, including the qualification (pass/fail) of the test material. The
material manufacturer shall include the result of the qualification test in datasheet reporting and
should make the qualification test result available to module manufacturers.

The test report shall apply to an encapsulant product, where no retesting is required, according
to IEC TS 62915.
NOTE Specimens that do not fulfil the pass/failure criteria prior to 4 000 cumulative h of weathering can be
discontinued from the test upon the agreement of the test lab and the material manufacturer. In the event of failure
prior to 4 000 cumulative h, the material does not qualify for use in a PV module (fail). The measured results will be
included in the test report, along with the cumulative duration used for examination.
12 Test report
A test report shall be prepared by the test agency; it shall contain the detail specification of the
test specimens and shall include at least the following minimum information:
a) a title;
b) name and address of the test laboratory and location where the tests were carried out;
c) unique identification of the report and of each page;
d) name and address of client, where appropriate;
e) description and identification of the item tested, including: specimen type; specimen
thickness (and its range of variation); specimen size (length and width); the type of
superstrate, encapsulant, and substrate material(s) used and their characteristics, including
UV cutoff wavelength;
f) characterization and condition of the test item, including the method and details of specimen
preparation (including curing, lamination, or similar processing if applicable), conditioning
used, and weathering;
g) date of receipt of test item and date(s) of test, where appropriate;
h) identification of test method used; including the make and model of the spectrophotometer
and the integrating sphere, and the make and model of the environmental chamber;
i) reference to sampling procedure, where relevant, including the batch number, position
within the roll, processing conditions, and equipment used to make the specimens;
j) any deviations from, additions to, or exclusions from, the test method and any other
information relevant to a specific test, such as environmental conditions; and the
procedure(s) and condition(s) used for weathering and any conditioning conducted prior to
measurements;
k) measurements, examinations and derived results supported by tables, graphs, sketches
and photographs as appropriate including the complete set of the tabulated average
transmittance values and the corresponding range of the averaged values; the estimated
uncertainty of the transmittance measurement (instrument); the averaged solar-weighted
transmittance of photon irradiance and the corresponding range of the averaged values; the
averaged representative solar-weighted transmittance of photon irradiance and the
corresponding range of the averaged values (as well as the wavelength range considered);
the UV cut-off wavelength and its uncertainty; and any failures observed;
l) the change in transmittance, yellowness index, and UV cut-off wavelength resulting from
weathering as well as an assessment of the change relative to the pass/failure criteria; the
results of visual inspection, relative to the pass/fail criteria;
m) the yellowness index and its uncertainty (which should be determined after weathering in
addition to its original value);
n) the tabulated average transmittance values and corresponding characteristics and its
uncertainty (averaged solar-weighted transmittance of photon irradiance, yellowness index,
and UV cut-off wavelength) of the superstrate, in its unaged and weathered condition;
o) a statement of the estimated uncertainty of the test results (where relevant); the
measurement of the witness specimen (if utilized) and its deviation from its witness values.
When applicable, the details of the witness specimen (such as its preparation, composition,
and thickness) shall be specified;
p) a statement describing the results of the visual inspection;

– 12 – IEC 62788-1-7:2020 © IEC 2020
q) a statement describing any additional visual observations, including the color, size, location,
and uniformity of discoloration of weathered specimens;
r) a signature and title, or equivalent identification of the person(s) accepting responsibility for
the content of the report, and the date of issue;
s) where relevant, a statement to the effect that the results relate only to the items tested;
t) a statement that the report shall not be reproduced except in full, without the written
approval of the laboratory;
u) other information as agreed to between the test laboratory and the customer.

Bibliography
[1] W. Thiemsorn, K. Keowkamnerd, S. Phanichphant, P. Suwannathada, H. Hessenkemper,
Influence of glass basicity on redox interactions of iron-manganese-copper ion pairs in
soda-lime-silica glass, Glass Phys. Chem., 34 (2008), 19-29
IEC 60904-3, Photovoltaic devices – Part 3: Measurement principles for terrestrial photovoltaic
(PV) solar devices with reference spectral irradiance data
IEC 61730-2, Photovoltaic (PV) module safety qualification – Part 2: Requirements for testing
IEC 62788-2 (all parts), Measurement procedures for materials used in photovoltaic modules

____________
– 14 – IEC 62788-1-7:2020 © IEC 2020
SOMMAIRE
AVANT-PROPOS . 15
INTRODUCTION . 17
1 Domaine d’application . 18
2 Références normatives . 19
3 Termes et définitions . 19
4 Principe . 19
5 Appareillage . 20
5.1 Spectrophotomètre pour le mesurage du facteur de transmission. 20
5.2 Chambre climatique pour l’exposition aux intempéries . 20
6 Éprouvettes d'essai . 20
6.1 Composants des éprouvettes et considérations générales pour tous les
types de matériaux. 20
6.2 Eprouvettes d’essai pour la consignation des informations dans les fiches
techniques . 20
6.3 Utilisation de matériaux alternatifs pour substrat et substrat inversé . 21
6.4 Éprouvettes témoins et contrôle expérimental . 21
7 Procédure de mesure . 22
8 Exposition aux intempéries artificielles accélérées . 22
9 Calcul et expression des résultats . 22
10 Procédure d’essai . 22
11 Critères de réussite/échec . 23
12 Rapport d’essai . 24
Bibliographie . 26

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
PROCÉDURES DE MESURE DES MATÉRIAUX UTILISÉS
DANS LES MODULES PHOTOVOLTAÏQUES –

Part 1-7: Encapsulants –
Procédure d’essai de la durabilité optique

AVANT-PROPOS
1) La Commission Électrotechnique 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. À 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 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.
4) Dans le but d'encourager l'uniformité internationale, les Comités nationaux de l’IEC s'engagent, dans toute la
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
conformité de l’IEC. L’IEC n'est responsable d'aucun des services effectués par les organismes de certification
indépendants.
6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à l'IEC, à ses administrateurs, employés, auxiliaires ou 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 62788-1-7 a été établie par le comité d’études 82 de l’IEC:
Systèmes de conversion photovoltaïque de l’énergie solaire.
Le texte de cette Norme internationale est issu des doc
...