SIST EN 62788-1-6:2017/A1:2020

• Status: Published
• Publication Date: 08-Sep-2020
• ICS: 27.160 - Solar energy engineering
• Technical Committee: PVS - Solar photovoltaic energy systems
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 07-Sep-2020
• Due Date: 12-Nov-2020
• Completion Date: 09-Sep-2020
• Ref Project: 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

• Refers: SIST EN ISO 14577-1:2026 - Metallic materials - Instrumented indentation test for hardness and materials parameters - Part 1: Test method (ISO 14577-1:2026)
• Effective Date: 01-Jul-2026
• Refers: SIST EN ISO 14577-1:2015 - Metallic materials - Instrumented indentation test for hardness and materials parameters - Part 1: Test method (ISO 14577-1:2015)
• Effective Date: 09-Feb-2026
• Refers: SIST EN ISO 6721-1:2019 - Plastics - Determination of dynamic mechanical properties - Part 1: General principles (ISO 6721-1:2019)
• Effective Date: 09-Feb-2026
• Amends: 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
• Effective Date: 01-Oct-2020

Overview

SIST EN 62788-1-6:2017/A1:2020 provides standardized measurement procedures for materials used in photovoltaic modules, specifically focusing on encapsulants. This amendment outlines test methods for determining the degree of cure in Ethylene-Vinyl Acetate (EVA), a widely used encapsulant material in the solar industry. Accurate assessment of EVA curing is essential for ensuring the long-term performance, reliability, and durability of photovoltaic (PV) modules. The standard aligns with international requirements, supporting quality assurance in solar panel manufacturing.

Key Topics

• Degree of Cure in EVA: Central to the standard is the determination of the curing or cross-linking level of EVA materials. This is vital for the mechanical stability and protection of PV modules.
• Test Methods: Guidance is provided on several test methods, including the widely used gel content method and a secondary indentation method, to assess the degree of cure.
• Indentation Method: The amendment introduces a secondary, non-destructive indentation technique to measure viscoelastic properties of EVA. This method is designed for in-line or production quality control and draws on instrumented indentation tests following ISO and EN standards.
• Sampling and Reporting: The standard formalizes sampling procedures, specimen handling, test setup, and comprehensive reporting requirements, ensuring data consistency and traceability.
• Correlation and Calibration: Procedures are described for establishing empirical correlations between different measurement methods (e.g., gel content and indentation), as well as requirements for regular calibration and validation of testing equipment.

Applications

SIST EN 62788-1-6:2017/A1:2020 is relevant to:

• PV Module Manufacturing: Manufacturers utilize these procedures to verify and control EVA curing during production, improving module reliability.
• Quality Control Laboratories: Accredited labs employ the specified test methods for batch verification and ensuring product compliance with industry standards.
• Material Suppliers: Suppliers of EVA and other encapsulant materials rely on these measurement protocols to qualify their products for use in PV modules.
• Research and Development: R&D teams use the defined test methods to evaluate new encapsulant formulations, ensuring optimal curing profiles and enhanced module performance.
• Process Optimization: The non-destructive indentation method enables continuous in-line monitoring, allowing for real-time process adjustments to optimize curing parameters and material utilization.

Related Standards

For comprehensive quality assurance and harmonization, this standard references and aligns with:

• IEC 62788-1-6: Base international standard for test methods on encapsulants in PV modules.
• ISO 6721-1: Plastics - Determination of dynamic mechanical properties - General principles, underpinning analysis of viscoelastic behavior.
• ISO 14577-1 / EN ISO 14577-1: Instrumented indentation test for hardness and materials parameters, applicable for the secondary indentation method.
• Other Photovoltaic Standards: This standard is part of a broader set for PV module component testing, often used alongside standards related to performance, durability, and safety of solar modules.

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Adoption of SIST EN 62788-1-6:2017/A1:2020 ensures that manufacturers and testing laboratories in the solar energy sector apply reliable, traceable, and internationally recognized methods for evaluating EVA encapsulant curing. This contributes to improved PV module durability, performance, and market acceptance, supporting broader solar energy deployment.

SLOVENSKI STANDARD
01-oktober-2020
Merilni postopki za materiale, uporabljene v fotonapetostnih modulih - 1-6. del:
Enkapsulanti - Preskusne metode za določanje stopnje strjevanja v etilen-vinilnih
acetatnih enkapsulantih - Dopolnilo A1
Measurement procedures for materials used in photovoltaic modules - Part 1-6:
Encapsulants - Test methods for determining the degree of cure in Ethylene-Vinyl
Acetate
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
Ta slovenski standard je istoveten z: EN 62788-1-6:2017/A1:2020
ICS:
27.160 Sončna energija Solar energy engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 62788-1-6:2017/A1

NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2020
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/A1:2020)
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/A1:2020) (IEC 62788-1-6:2017/A1:2020)
This amendment A1 modifies the European Standard EN 62788-1-6:2017; it was approved by CENELEC on 2020-06-30. CENELEC
members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this amendment 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 amendment 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, 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: Rue de la Science 23, B-1040 Brussels
© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 62788-1-6:2017/A1:2020 E

European foreword
The text of document 82/1691/FDIS, future IEC 62788-1-6/A1, 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/A1:2020.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2021-03-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2023-06-30
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 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/A1:2020 was approved by CENELEC as a
European Standard without any modification.

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where 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.
Add the following references:
Publication Year Title EN/HD Year
ISO 6721-1 - Plastics - Determination of dynamic mechanical EN ISO 6721-1 -
properties - Part 1: General principles
ISO 14577-1 - Metallic materials - Instrumented indentation EN ISO 14577-1 -
test for hardness and materials parameters -
Part 1: Test method
IEC 62788-1-6 ®
Edition 1.0 2020-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 1
AM ENDEMENT 1
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 vinyl

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-8209-0

– 2 – IEC 62788-1-6:2017/AMD1:2020
© IEC 2020
FOREWORD
This amendment has been prepared by IEC technical committee 82:Solar photovoltaic energy
systems.
The text of this amendment is based on the following documents:
FDIS Report on voting
82/1691/FDIS 82/1720/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base 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.
_____________
2 Normative references
Add the following new references:
ISO 6721-1, Plastics – Determination of dynamic mechanical properties – Part 1: General
principles
ISO 14577-1, Metallic materials – Instrumented indentation test for hardness and materials
parameters – Part 1: Test method
3 Terms and definitions
Add the following new term:
3.6
degree of cure
G
i
parameter that correlates with the extent of cross-linking within the EVA
using the indentation method
Note 1 to entry: Unit: dimensionless.
5.2.1 Sampling and storage
Replace the existing subclause 5.2.1.1 with the following:

IEC 62788-1-6:2017/AMD1:2020 – 3 –
© IEC 2020
5.2.1.1
Because the results for the secondary method may depend on the make of EVA, test results
may only be directly compared for the same formulation of EVA. Therefore, test specimens
should come from the same manufacturer(s) for the same fabrication lay-up configuration
(backsheet/EVA combination). Changes in the encapsulant that affect the curing process,
including but not limited to a change of the material supplier, would require validating the
correlation between G and the degree of cure. For example, if the percentage vinyl acetate
%
and the degree of cure (from
content in the EVA resin changes, a new correlation between G
%
a secondary method) should be obtained because the percentage vinyl acetate content is
known to significantly affect the viscoelastic-dependent cure characteristics of the
encapsulant.
7 Test report
Replace the existing item h) with the following:
h) identification of test method used and test instrument and other equipment used, including
the laminator and the temperature, pressure, and time settings used, when applicable. In
the case of the indentation secondary method (per correlation or usual use of method), the
test temperature, tip material, tip geometry, and tip size, maximum indentation load,
maximum indentation depth, and frequency of modulation (if applicable) shall also be
reported;
Replace the existing item i) with the following:
i) reference to sampling procedure, where relevant, including the number of tests per
specimen;
Replace the existing item k) with the following:
k) measurements (associated and their uncertainty), examinations and derived results
supported by tables, graphs, sketches and photographs as appropriate including degree of
cure, specimen mass, measured enthalpy, graphs of the enthalpy/temperature data,
graphs of the crystallization peaks, and gel content;
Add the following new clause:
8 Indentation secondary method
8.1 General
An alternative secondary method, using indentation to characterize the degree of cu
...