EN 62925:2017

Concentrator photovoltaic (CPV) modules - Thermal cycling test to differentiate increased thermal fatigue durability

IEC 62108:2016 defines a test sequence that will quickly uncover CPV module failures that have been associated with field exposure to thermal cycling for many years. This document was specifically developed to relate to thermal fatigue failure of the HCPV die-attach, however, it also applies, to some extent, to all thermal fatigue related failure mechanisms for the assemblies submitted to test.

Konzentrator-Photovoltaik (CPV)-Module - Temperaturwechselprüfung für CPV-Module zur Bewertung erhöhter Temperaturwechselbeständigkeit

Modules photovoltaïques à concentration (CPV) - Essai de cycles thermiques pour la détermination de la durabilité renforcée à la fatigue thermique

L'IEC 62108:2016 définit une séquence d’essais permettant de détecter rapidement les défaillances du module CPV associées à une exposition aux cycles thermiques sur le terrain pendant de nombreuses années. Le présent document a été conçu dans le but spécifique de traiter des défaillances de fatigue thermique de la fixation de puce photovoltaïque à haute concentration (HCPV : high concentrator photovoltaic). Cependant, il s'applique également, dans une certaine mesure, à tous les mécanismes de défaillance liés à la fatigue thermique des ensembles soumis à l'essai.

Koncentratorski fotonapetostni moduli (CPV) - Ciklični temperaturni preskus razvrstitve glede na povečano odpornost proti temperaturni utrujenosti

Ta dokument določa preskusno zaporedje, ki bo hitro odkrilo okvare koncentratorskih fotonapetostnih modulov zaradi večletne izpostavljenosti cikličnim temperaturam na terenu. Ta dokument je bil razvit posebej za okvare zaradi temperaturne utrujenosti vezij HCPV, vendar se lahko v določeni meri uporablja tudi za vse mehanizme odpovedi v zvezi s temperaturno utrujenostjo pri preskušanih sestavih.
Preskus ugotavljanja primernosti koncentratorskih fotonapetostnih modulov iz standarda IEC 62108 že vključuje pospešeno ciklično temperaturno zaporedje v enem delu preskušanja, vendar pa parametri tega preskusa označujejo samo kvalifikacijsko raven izpostavljenosti. Ta preskusni postopek uporablja večjo obremenitev in omogoča primerjalno preskušanje za razvrščanje koncentratorskih fotonapetostnih modulov glede na povečano odpornost proti cikličnim temperaturam in povezanim mehanskim obremenitvam.

General Information

• Status: Published
• Publication Date: 04-May-2017
• Withdrawal Date: 04-May-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 62925:2017 - Concentrator photovoltaic (CPV) modules - Thermal cycling test to differentiate increased thermal fatigue durability

Overview

EN 62925:2017 (identical to IEC 62925:2016) specifies a thermal cycling test for concentrator photovoltaic (CPV) modules to differentiate increased thermal fatigue durability. Developed as a supplement to IEC 62108, this standard targets failure modes linked to repeated temperature cycling in field-deployed CPV systems - most notably thermal fatigue of high-concentration PV (HCPV) die-attach - but is applicable to other thermal-fatigue-related failure mechanisms in module and receiver assemblies.

Key topics and requirements

• Scope & purpose: Defines an accelerated test sequence designed to quickly uncover CPV module failures caused by thermal cycling and to provide a comparative route for modules with improved durability.
• Sampling: For non-field-adjustable-focus CPV modules, submissions should include modules containing at least 20 separate PV cells (more encouraged). Test failure is based on failure of 5% of submitted cells.
• Test sequence: Structured into distinct phases - cell evaluation, thermal cycling (accelerated and more severe than IEC 62108 qualification levels), and subsequent outdoor exposure to validate post-test behavior.
• Test procedure elements: Guidance on disassembly/reassembly of receivers to reduce thermal mass, temperature cycling parameters (ramp rates and number of cycles), and requirements for reassembly before outdoor exposure.
• Marking & reporting: Requirements for clear, indelible markings (manufacturer, type/model, serial number, polarity, maximum system voltage) and standardized reporting of results, rating, and any modifications.
• Objective metrics: The standard provides pass/fail criteria tied to cell failures and calls for documented test reports and ratings to enable comparison between products.

Practical applications and users

EN 62925:2017 is used to:

• Help manufacturers validate design changes aimed at improving thermal fatigue resistance (especially die-attach designs).
• Allow test laboratories to perform comparative durability testing to support product claims.
• Support procurement teams and project developers in selecting CPV modules with demonstrable resistance to thermal cycling.
• Guide R&D teams and reliability engineers in failure analysis and design optimization for long-term field performance.
• Complement qualification programs and inform asset owners about module durability in harsh thermal environments.

Related standards

• IEC 62925:2016 - International edition (identical content)
• IEC 62108:2016 / EN 62108:2016 - Design qualification and type approval for CPV modules; EN 62925 is intended as a supplemental, more rigorous thermal-fatigue differentiation test.

Keywords: EN 62925:2017, IEC 62925, CPV modules, concentrator photovoltaic, thermal cycling test, thermal fatigue, die-attach, HCPV, durability, IEC 62108.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2017
.RQFHQWUDWRUVNLIRWRQDSHWRVWQLPRGXOL&39&LNOLþQLWHPSHUDWXUQLSUHVNXV
UD]YUVWLWYHJOHGHQDSRYHþDQRRGSRUQRVWSURWLWHPSHUDWXUQLXWUXMHQRVWL
Concentrator photovoltaic (CPV) modules - Thermal cycling test to differentiate
increased thermal fatigue durability
CPV-Module - Temperaturwechselprüfung für CPV-Module zur Bewertung erhöhter
Temperaturwechselbeständigkeit
Modules photovoltaïques à concentration (CPV) - Essai de cycles thermiques pour la
détermination de la durabilité renforcée à la fatigue thermique
Ta slovenski standard je istoveten z: EN 62925:2017
ICS:
27.160 6RQþQDHQHUJLMD Solar energy engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 62925
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2017
ICS 27.160
English Version
Concentrator photovoltaic (CPV) modules - Thermal cycling test
to differentiate increased thermal fatigue durability
(IEC 62925:2016)
Modules photovoltaïques à concentration (CPV) - Essai de CPV-Module - Temperaturwechselprüfung für CPV-Module
cycles thermiques pour la détermination de la durabilité zur Bewertung erhöhter Temperaturwechselbeständigkeit
renforcée à la fatigue thermique (IEC 62925:2016)
(IEC 62925:2016)
This European Standard was approved by CENELEC on 2017-01-18. 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 62925:2017 E
European foreword
The text of document 82/1185/FDIS, future edition 1 of IEC 62925, prepared by IEC/TC 82 "Solar
photovoltaic energy systems" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 62925:2017.
The following dates are fixed:
(dop) 2017-11-05
• latest date by which the document has to be implemented at
national level by publication of an identical national
standard or by endorsement
(dow) 2020-05-05
• latest date by which the national 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 62925:2016 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, 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 62108 2016 Concentrator photovoltaic (CPV) EN 62108 2016
modules and assemblies - Design
qualification and type approval

IEC 62925 ®
Edition 1.0 2016-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Concentrator photovoltaic (CPV) modules – Thermal cycling test to differentiate

increased thermal fatigue durability

Modules photovoltaïques à concentration (CPV) – Essai de cycles thermiques

pour la détermination de la durabilité renforcée à la fatigue thermique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-3725-0

– 2 – IEC 62925:2016 © IEC 2016
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Sampling . 7
5 Marking . 7
6 Testing . 8
7 Rating. 8
8 Report . 8
9 Modifications . 9
10 Test procedure . 9
10.1 General . 9
10.2 Cell evaluation . 9
10.2.1 Purpose . 9
10.2.2 Procedure . 10
10.2.3 Requirements . 10
10.3 Thermal cycling. 10
10.3.1 Purpose . 10
10.3.2 Test sample . 10
10.3.3 Procedure . 10
10.4 Outdoor exposure test . 12
10.4.1 Purpose . 12
10.4.2 Procedure . 12
Bibliography . 13

Figure 1 – Number of required cycles as a function of average temperature ramp rate
in order to complete an equivalent test . 11
Figure 2 – Overall test time as a function of temperature ramp rate . 12

IEC 62925:2016 © IEC 2016 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONCENTRATOR PHOTOVOLTAIC (CPV) MODULES –
THERMAL CYCLING TEST TO DIFFERENTIATE
INCREASED THERMAL FATIGUE DURABILITY

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
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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 62925 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
The text of this standard is based on the following documents:
FDIS Report on voting
82/1185/FDIS 82/1210/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.

– 4 – IEC 62925:2016 © IEC 2016
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.
IEC 62925:2016 © IEC 2016 – 5 –
INTRODUCTION
IEC 62108 defines IEC requirements for the design qualification of concentrator modules for
long-term operation in general open-air climates. This standard, IEC 62925, is not compulsory
with but will supplement IEC 62108 by providing tests that differentiate thermal fatigue
durability of concentrator modules for deployment in a larger range of applications and
climates.
– 6 – IEC 62925:2016 © IEC 2016
CONCENTRATOR PHOTOVOLTAIC (CPV) MODULES –
THERMAL CYCLING TEST TO DIFFERENTIATE
INCREASED THERMAL FATIGUE DURABILITY

1 Scope
This document defines a test sequence that will quickly uncover CPV module failures that
have been associated with field exposure to thermal cycling for many years. This document
was specifically developed to relate to thermal fatigue failure of the HCPV die-attach, however,
it also applies, to some extent, to all thermal fatigue related failure mechanisms for the
assemblies submitted to test.
IEC 62108, the CPV module qualification test already includes an accelerated thermal cycle
sequence in one leg of the testing, however, the parameters of that test only represent a
qualification level of exposure. This test procedure applies more stress and will provide a
route for comparative testing to differentiate CPV modules with improved durability to thermal
cycling and the associated mechanical stresses.
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 62108:2016, Concentrator photovoltaic (CPV) modules and assemblies – Design
qualification and type approval
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
...