EN 62788-1-6:2017

Measurement procedures for materials used in photovoltaic modules - Part 1-6: Encapsulants - Test methods for determining the degree of cure in Ethylene-Vinyl Acetate

IEC 62788-1-6:2017 defines the terminology, test equipment, test environment, specimen preparation, test procedures, and test report for measuring the degree of cure of Ethylene-Vinyl Acetate (EVA) encapsulation sheet used in photovoltaic (PV) modules. The differential scanning calorimetry (both residual enthalpy and melt/freeze protocols) and gel content methods are included herein. This procedure can be used by material- or module-manufacturers to verify that the cross-linking additive is present and is active. The procedure can also be used to verify the module manufacturing (lamination) process for the purposes of quality- and process-control. The procedure can also be used to assess the uniformity of the EVA formulation within a roll as well as to compare variation of the EVA formulation from roll to roll.

Messverfahren für Werkstoffe, die in Photovoltaik-Modulen verwendet werden - Teil 1-6: Verkapselungsstoffe - Prüfverfahren zur Bestimmung des Aushärtungsgrads der Ethylen-Vinyl-Acetat-Verkapselung

Procédures de mesure des matériaux utilisés dans les modules photovoltaïques - Partie 1-6: Encapsulants - Méthodes d'essai pour déterminer le degré de durcissement dans l'éthylène-acétate de vinyle

L’IEC 62788-1-6:2017 définit la terminologie, l'équipement d'essai, l'environnement d'essai, la préparation des éprouvettes, les procédures d'essai et le rapport d'essai pour le mesurage du degré de durcissement de la couche d'encapsulation en éthylène-acétate de vinyle (EVA) utilisée dans les modules photovoltaïques (PV). Les méthodes de l'analyse calorimétrique différentielle à balayage (protocoles d'enthalpie résiduelle et de fusion/gel) et du taux de gel sont incluses dans le présent document. Cette procédure peut être utilisée par les fabricants de matériaux ou de modules pour s'assurer que l'additif de réticulation est présent et actif. La procédure peut également être utilisée pour vérifier le procédé de fabrication (stratification) du module à des fins de contrôle de la qualité et des processus. Elle peut en outre être utilisée pour évaluer l'uniformité de la formulation d’EVA dans un rouleau et comparer les différences de formulation d’EVA d'un rouleau à l'autre.

Merilni postopki za materiale, uporabljene v fotonapetostnih modulih - 1-6. del: Enkapsulanti - Preskusne metode za določanje stopnje strjevanja v etilen-vinilnih acetatnih enkapsulantih

Ta del standarda IEC 62788 določa terminologijo, opremo za preskušanje, preskusno okolje, pripravo vzorcev, preskusne postopke in poročila o preskusih za merjenje stopnje strjevanja v etilen-vinilnih acetatnih (EVA) enkapsulantih, ki se uporabljajo v fotonapetostnih (PV) modulih. V tem delu so vključene metode diferenčne dinamične kalorimetrije (residualna entalpija ter protokoli taljenja/zamrzovanja) in ugotavljanja deleža gela. S pomočjo tega postopka lahko proizvajalci materiala ali modulov preverijo, ali je aditiv za prečno povezovanje prisoten in aktiven. S tem postopkom se lahko preveri tudi postopek proizvodnje modulov (laminacija) za namene nadzora kakovosti in procesov.
Postopek se lahko uporabi tudi za ocenjevanje enotnosti sestave etilen-vinilnih acetatnih enkapsulantov v zvitku in tudi za primerjavo spreminjanje sestave etilen-vinilnih acetatnih enkapsulantov med zavitki. Ta postopek se lahko uporablja pri nestrjenih ali nedavno strjenih ploščah etilen-vinilnih acetatnih enkapsulantov in pri nestrjenih ali nedavno strjenih etilen-vinilnih acetatnih enkapsulantih v fotonapetostnih modulih.
Ta preskusni postopek se lahko uporablja pri drugih etilenskih kopolimerih za prečno povezovanje.
Temperature, določene za merjenje s kalorimetrom pri tem postopku, so optimizirane za etilen-vinilne acetatne enkapsulante. Če se preskusni postopek uporablja pri drugih materialih za enkapsulacijo, je morda treba prilagoditi temperaturna območja pri preskusu na podlagi aktivne temperature strjevalnega sredstva in/ali temperature taljenja/zamrzovanja osnovnega materiala.

General Information

• Status: Published
• Publication Date: 04-May-2017
• Withdrawal Date: 02-Mar-2020
• ICS: 27.160 - Solar energy engineering
• Technical Committee: CLC/TC 82 - Solar photovoltaic energy systems
• Drafting Committee: IEC/TC 82 - IEC_TC_82
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 05-May-2017
• Completion Date: 05-May-2017
• Ref Project: SIST EN 62788-1-6:2017 - Measurement procedures for materials used in photovoltaic modules - Part 1-6: Encapsulants - Test methods for determining the degree of cure in Ethylene-Vinyl Acetate

Relations

• Amended By: EN 62788-1-6:2017/A1:2020 - Measurement procedures for materials used in photovoltaic modules - Part 1-6: Encapsulants - Test methods for determining the degree of cure in Ethylene-Vinyl Acetate
• Effective Date: 27-Feb-2018

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2017
0HULOQLSRVWRSNL]DPDWHULDOHXSRUDEOMHQHYIRWRQDSHWRVWQLKPRGXOLKGHO
(QNDSVXODQWL3UHVNXVQHPHWRGH]DGRORþDQMHVWRSQMHVWUMHYDQMDYHWLOHQYLQLOQLK
DFHWDWQLKHQNDSVXODQWLK
Measurement procedures for materials used in photovoltaic modules - Part 1-6:
Encapsulants - Test methods for determining the degree of cure in Ethylene-Vinyl
Acetate
Werkstoffe, die in photovoltaischen Modulen verwendet werden – Messverfahren - Teil 1
-6: Verkapselungsstoffe – Prüfverfahren zur Bestimmung des Aushärtungsgrads der
Ethylen-Vinyl-Acetat-Verkapselung
Procédures de mesure des matériaux utilisés dans les modules photovoltaïques - Partie
1-6: Encapsulants - Méthodes d'essai pour déterminer le degré de durcissement dans
l'éthylène-acétate de vinyle
Ta slovenski standard je istoveten z: EN 62788-1-6:2017
ICS:
27.160 6RQþQDHQHUJLMD Solar energy engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 62788-1-6

NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2017
ICS 27.160
English Version
Measurement procedures for materials used in photovoltaic
modules - Part 1-6: Encapsulants - Test methods for determining
the degree of cure in Ethylene-Vinyl Acetate
(IEC 62788-1-6:2017)
Procédures de mesure des matériaux utilisés dans les Werkstoffe, die in photovoltaischen Modulen verwendet
modules photovoltaïques - Partie 1-6: Encapsulants - werden - Messverfahren - Teil 1-6: Verkapselungsstoffe -
Méthodes d'essai pour déterminer le degré de Prüfverfahren zur Bestimmung des Aushärtungsgrads der
durcissement dans l'éthylène-acétate de vinyle Ethylen-Vinyl-Acetat-Verkapselung
(IEC 62788-1-6:2017) (IEC 62788-1-6:2017)
This European Standard was approved by CENELEC on 2017-03-03. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 62788-1-6:2017 E
European foreword
The text of document 82/1197/FDIS, future edition 1 of IEC 62788-1-6, prepared by IEC/TC 82 “Solar
photovoltaic energy systems" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 62788-1-6:2017.
The following dates are fixed:
(dop) 2017-12-03
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-03-03
standards conflicting with the
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 62788-1-6:2017 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 61215 (series) NOTE Harmonized as EN 61215 (series).
ISO 11357-2 NOTE Harmonized as EN ISO 11357-2.
ISO 11357-3 NOTE Harmonized as EN ISO 11357-3.

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 61215-1 -  Terrestrial photovoltaic (PV) modules - EN 61215-1 -
Design qualification and type approval -
Part 1: Test requirements
ISO 291 2008 Plastics - Standard atmospheres for EN ISO 291 2008
conditioning and testing
ISO 6427 2013 Plastics - Determination of matter EN ISO 6427 2014
extractable by organic solvents
(conventional methods)
ISO 10147 -  Pipes and fittings made of crosslinked EN ISO 10147 2012
polyethylene (PE-X) - Estimation of the
degree of crosslinking by determination of
the gel content
ISO 11357-1 2009 Plastics - Differential scanning calorimetry - -
(DSC) - Part 1: General principles
ISO/IEC 17025 2005 General requirements for the competence EN ISO/IEC 17025 2005
of testing and calibration laboratories
ASTM D2765-11 -  Standard Test Methods for Determination - -
of Gel Content and Swell Ratio of
Crosslinked Ethylene Plastics
IEC 62788-1-6 ®
Edition 1.0 2017-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Measurement procedures for materials used in photovoltaic modules –

Part 1-6: Encapsulants – Test methods for determining the degree of cure in

Ethylene-Vinyl Acetate
Procédures de mesure des matériaux utilisés dans les modules

photovoltaïques –
Partie 1-6: Encapsulants – Méthodes d'essai pour déterminer le degré de

durcissement dans l'éthylène-acétate de vinyle

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-3857-8

– 2 – IEC 62788-1-6:2017 © IEC 2017
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Principle . 7
5 DSC secondary method . 8
5.1 Instrument and equipment for the secondary method . 8
5.1.1 General . 8
5.1.2 Electronic balance . 8
5.1.3 Differential scanning calorimeter . 8
5.1.4 Instrument calibration . 8
5.2 Specimen preparation for the secondary method. 9
5.2.1 Sampling and storage . 9
5.2.2 Preparation procedures . 9
5.3 Test requirements for the secondary method . 9
5.3.1 Environment requirements . 9
5.3.2 Parameter settings (residual enthalpy method) . 10
5.3.3 Parameter settings (melt/freeze method) . 10
5.3.4 Parameter settings (combined enthalpy and melt/freeze method) . 10
5.4 Test procedure for the secondary method . 11
5.5 Calculation and expression of the results for the secondary method . 11
5.5.1 Enthalpy method . 11
5.5.2 Melt/freeze method . 12
5.6 Uncertainty of measurements for the secondary method . 16
6 The primary method . 16
6.1 Principle for the primary method . 16
6.2 Instrument and equipment for the primary method . 17
6.2.1 Electronic balance . 17
6.2.2 Soxhlet extractor . 17
6.2.3 Thimble . 17
6.2.4 Heating apparatus . 17
6.2.5 Handling apparatus. 18
6.2.6 Solvent . 18
6.3 Specimen preparation for the primary method . 18
6.3.1 Sampling and storage . 18
6.3.2 Preparation procedures . 18
6.4 Test requirements for the primary method – Environment requirements . 19
6.5 Test procedure for the primary method . 19
6.6 Calculation and expression of the results for the primary method . 19
7 Test report . 19
Annex A (informative) Limitations of the primary and secondary measurement methods
...................................................................................................................................... 21
Bibliography . 23

Figure 1 – Example result for the DSC residual enthalpy method . 12

IEC 62788-1-6:2017 © IEC 2017 – 3 –
Figure 2 – Location of temperatures and temperature ranges used in the melt/freeze DSC
method . 13
Figure 3 – Example of the temperature bounds applied for an automated software
integration algorithm . 14
Figure 4 – Representation of the measurement profile for an EVA test specimen . 16

Table 1 – Summary of the results for the example measurements shown in Figure 2 . 14

– 4 – IEC 62788-1-6:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEASUREMENT PROCEDURES FOR MATERIALS USED
IN PHOTOVOLTAIC MODULES –
Part 1-6: Encapsulants – Test methods for determining
the degree of cure in Ethylene-Vinyl Acetate

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 international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in
addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations lia
...