IEC TS 62915:2018

Photovoltaic (PV) modules - Type approval, design and safety qualification - Retesting

IEC TS 62915:2018(E) sets forth a uniform approach to maintain type approval, design and safety qualification of terrestrial PV modules that have undergone, or will undergo modification from their originally assessed design. Changes in material selection, components and manufacturing process can impact electrical performance, reliability and safety of the modified product. This document lists typical modifications and the resulting requirements for retesting based on the different test standards. This document is closely related to the IEC 61215 and IEC 61730 series of standards.

General Information

• Status: Published
• Publication Date: 06-May-2018
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: WG 2 - TC 82/WG 2
• Current Stage: DELPUB - Deleted Publication
• Start Date: 15-Sep-2023
• Completion Date: 04-Sep-2020

Relations

• Revised: IEC TS 62915:2023 - Photovoltaic (PV) modules - Type approval, design and safety qualification - Retesting
• Effective Date: 05-Sep-2023

Overview

IEC TS 62915:2018 defines a uniform, engineering‑based approach for retesting terrestrial photovoltaic (PV) modules after design, material, component or manufacturing changes. The Technical Specification helps maintain type approval, design qualification and safety qualification for PV modules whose originally assessed design has been modified. It lists typical modifications, identifies which tests are required to detect adverse impacts on electrical performance, reliability and safety, and points to the pass/fail criteria and sample sizes given in the referenced standards.

Key topics and requirements

• Scope of retesting: Applies to changes in materials, components, processing, module size, output power, electrical terminations, frames, edge sealing, bypass diodes, interconnects, and more. Organized separately for crystalline silicon and thin‑film PV technologies.
• Test selection principle: Retests are chosen to reveal adverse effects of the modification; materials in direct contact must be evaluated in all applicable combinations.
• Reference to pass criteria: Number of samples and pass/fail criteria are taken from the relevant clauses of IEC 61215 (design qualification/type approval) and IEC 61730 (module safety).
• Annexed guidance: Annex A provides tabular overviews of required retests for crystalline and thin‑film modules, combined IEC 61215/61730 test flows, and a procedure for testing new material combinations.
• Limitations: Does not address tests required solely because of updates between different editions of IEC 61215 or IEC 61730 - those are handled separately.

Practical applications

Who uses IEC TS 62915:2018 and why:

• PV manufacturers - to determine which qualification tests are required when modifying product design, materials or processes and to maintain product certification.
• Independent test laboratories - to design retest programs and interpret which IEC test sequences apply for specific modifications.
• Certification bodies - to assess continued compliance of a module family after design changes.
• System designers and asset owners - to understand risk implications of modified modules on long‑term reliability and safety.

Benefits:

• Reduces uncertainty when implementing design or material changes.
• Helps avoid unnecessary full requalification while ensuring safety and performance.
• Provides consistent, repeatable retest procedures aligned to IEC test suites.

Related standards

• IEC 61215 (all parts) - Terrestrial PV modules: design qualification and type approval (test requirements and procedures)
• IEC 61730 (all parts) - PV module safety qualification (requirements for construction)
• IEC TS 61836, IEC 62790 - referenced for terms, definitions and junction box testing

Keywords: IEC TS 62915:2018, PV modules retesting, type approval, design qualification, safety qualification, IEC 61215, IEC 61730, crystalline silicon, thin‑film, material changes, retest program.

Standards Content (Sample)

IEC TS 62915 ®
Edition 1.0 2018-05
TECHNICAL
SPECIFICATION
colour
inside
Photovoltaic (PV) modules – Type approval, design and safety qualification –
Retesting
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IEC TS 62915 ®
Edition 1.0 2018-05
TECHNICAL
SPECIFICATION
colour
inside
Photovoltaic (PV) modules – Type approval, design and safety qualification –

Retesting
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-5615-2

– 2 – IEC TS 62915:2018 © IEC 2018
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Retesting . 7
4.1 General . 7
4.2 Test programs for crystalline silicon PV modules . 8
4.2.1 Modification to frontsheet . 8
4.2.2 Modification to encapsulation system . 9
4.2.3 Modification to cell technology . 10
4.2.4 Modification to cell and string interconnect material or technique . 10
4.2.5 Modification to backsheet . 11
4.2.6 Modification to electrical termination . 12
4.2.7 Modification to bypass diode . 12
4.2.8 Modification to electrical circuitry . 13
4.2.9 Modification to edge sealing . 13
4.2.10 Modification to frame and/or mounting structure . 14
4.2.11 Change in PV module size . 14
4.2.12 Higher or lower output power (by 10 % or more) with the identical
design and size and using the identical cell process . 15
4.2.13 Increase of over-current protection rating . 15
4.2.14 Increase of system voltage . 15
4.2.15 Change in cell fixing tape . 15
4.3 Test programs for thin-film PV modules . 15
4.3.1 Modification to frontsheet . 16
4.3.2 Modification to encapsulation system . 16
4.3.3 Modification to front contact (e. g. TCO) . 17
4.3.4 Modification to cell technology . 17
4.3.5 Modification to cell layout . 18
4.3.6 Modification to back contact . 18
4.3.7 Modification to edge deletion . 19
4.3.8 Modification to interconnect material or technique . 19
4.3.9 Modification to backsheet . 19
4.3.10 Modification to electrical termination . 20
4.3.11 Modification to bypass diode . 21
4.3.12 Modification to edge sealing . 22
4.3.13 Modification to frame and/or mounting structure . 22
4.3.14 Change in PV module size . 23
4.3.15 Higher or lower output power (by 10 % or more) with the identical
design and size . 23
4.3.16 Increase of over-current protection rating . 23
4.3.17 Increase of system voltage . 23
Annex A (informative) . 25
A.1 Required retests for crystalline silicon PV modules, tabular overview . 25
A.2 Required retests for thin-film PV modules, tabular overview . 27
A.3 Combined test flow IEC 61215 and IEC 61730 (see Figure A.1 and Table A.3) . 29
A.4 Tests for new combinations of material in direct contact with each other . 31

Figure A.1 – Combined test flow IEC 61215 and IEC 61730 . 29
Figure A.2 – Illustration of example for required tests for new material combinations . 33

Table A.1 – Required retests for crystalline silicon PV modules . 25
Table A.2 – Required retests for thin-film silicon PV modules . 27
Table A.3 – IEC identifiers for test sequences . 30
Table A.4 – Example for required tests for new material combinations . 32

– 4 – IEC TS 62915:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOVOLTAIC (PV) MODULES – TYPE APPROVAL,
DESIGN AND SAFETY QUALIFICATION – RETESTING

FOREWORD
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Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC TS 62915, which is a technical specification, has been prepared by IEC technical
committee 82: Solar photovoltaic energy systems.

The text of this technical specification is based on the following documents:
Enquiry draft Reports on voting
82/1331/DTS 82/1378A/RVDTS
Full information on the voting for the approval of this technical specification 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.
The committee has decided that the contents of this publication will remain unchanged until
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– 6 – IEC TS 62915:2018 © IEC 2018
PHOTOVOLTAIC (PV) MODULES – TYPE APPROVAL,
DESIGN AND SAFETY QUALIFICATION – RETESTING

1 Scope
This document sets forth a uniform approach to maintain type approval, design and safety
qualification of terrestrial PV modules that have undergone, or will undergo modification from
their originally assessed design.
Changes in material selection, components and manufacturing process can impact electrical
performance, reliability and safety of the modified product. This document lists typical
modifications and the resulting requirements for retesting based on the different test
standards. It provides assistance; at some level engineering judgement may be needed.
The test sequences are selected to identify adverse changes to the modified product.
Those products successfully following the herein defined test sequences are considered to be
compliant with the standard against which they have originally been assessed in a full
qualification.
The number of samples to be included in the retesting program and the pass/fail criteria are
listed in the referenced standards IEC 61215 and IEC 61730.
Tests required by changes from previous to new standard editions of IEC 61215 and
IEC 61730 are not covered by this document and are evaluated separately.
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 (all parts), Terrestrial photovoltaic (PV) modules – Design qualification and type
approval
IEC 61215-1:2016, Terrestrial photovoltaic (PV) modules – Design qualification and type
approval – Part 1: Test requirements
IEC 61215-2:2016, Terrestrial photovoltaic (PV) modules – Design qualification and type
approval – Part 2: Test procedures
IEC 61730 (all parts), Photovoltaic (PV) module safety qualification
IEC 61730-1:2016, Photovoltaic (PV) module safety qualification – Part 1: Requirements for
construction
IEC TS 61836, Solar photovoltaic energy systems – Terms, definitions and symbols
IEC 62790, Junction boxes for photovoltaic modules – Safety requirements and tests

3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61215-1,
IEC 61215-2, IEC 61730-1 and IEC TS 61836, as well as the following 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
3.1
different material
material that differs in its chemical composition, type designation, or specification from the
material it replaces
3.2
nominal value
value of a quantity used to designate and identify a component, device, equipment, or system
[SOURCE IEC 60050-151:2001, 151-16-09]
3.3
tolerance
permitted deviation of declared nominal value
4 Retesting
4.1 General
This clause is separated into one subclause each for crystalline silicon and for thin-film
technologies. The document is organized by major modification headings with specific
supporting examples and parenthetical reference to the specific clauses of the relevant IEC
standards.
Any change in the design, materials, components, material combinations, manufacturers or
processing of the PV module type family from the last tested version may require a repetition
of some or all of the qualification tests according to the clauses that follow in order to
maintain type and safety approval. For any change in material specification, including, e.g.,
electrical, optical, mechanical properties, the nominal values and tolerances shall be
considered. For any assessment of a new thickness or dimension, the initially tested
thickness or dimension shall be used as reference. Any variation of a parameter may be
assessed as change if the new value is out of the tolerance from the nominal value of this
parameter.
Materials in direct contact with each other shall be tested in all applicable combinations. The
required test items shall be selected only from those tests which are applicable for change of
both materials. An example for an assessment procedure is given in Annex A, Clause A.4.
The number of samples to be included in the retesting program and the pass criteria are to be
taken from the relevant clause/subclause of the referenced standards (‘pass criteria’).
Each PV module delivered for retesting shall be subjected to electrical stabilisation (MQT 19),
as applicable by the relevant type approval standard.
All initial measurements as listed in the referenced standards shall be performed before the
specific tests, e.g. tests MQT 01 / 03 / 06.1 / 15 / 19 for an IEC 61215 retest program.

– 8 – IEC TS 62915:2018 © IEC 2018
Any scenario including a change in the optical path or electric circuitry that requires retesting
as defined hereinafter shall include an STC output power measurement (MQT 06.1). The
measured stabilized power, open-circuit voltage and short-circuit current shall be assessed
against the rating (Gate No. 1), and the relative change in output power shall be assessed
(Gate No. 2) according to the pass criteria laid down in the standard (see IEC 61215-1:2016,
7.2).
Final diagnostic measurements are listed in the referenced test procedure; as a minimum the
same tests as performed initially shall be performed.
The Durability of markings (MST 05) and the Sharp edge test (MST 06) need to be considered
in general for all design changes which may impact the results of these tests.
If multiple tests from a test sequence are required, they shall be done in the sequence
prescribed by the referenced standard.
Changes in the PV module design might require assessment against IEC 61730-1
(requirements for construction) besides the indicated test programs.
Required tests in this Clause 4 are written for combined IEC 61215 (all parts) and IEC 61730
(all parts) evaluations. For simplification, the term “all parts” is omitted in the following. For
single IEC 61730 evaluations, care has to be taken that tests listed herein for IEC 61215 may
also be referenced and required by IEC 61730 to ensure compliance.
4.2 Test programs for crystalline silicon PV modules
NOTE See Table A.1 for a summary of the retest requirements for crystalline silicon PV modules.
4.2.1 Modification to frontsheet
A change from glass to non-glass or vice-versa requires a full qualification.
For the following modifications:
• Different material, i.e. any change in specification of the material or any of its layers
• Glass: reduction of thickness by more than 10 %; non-glass: change of thickness by more
than 20 % of any one of the individual layers (while maintaining the required minimum
distance through insulation)
• For glass, if there is a reduction in the strengthening process (for example retest if change
is from tempered glass to heat strengthened or annealed)
• Different surface treatment, e.g. any coating on frontsheet (inside or outside)
• Change of amount of adhesives, primers or other additives
• Addition or removal of adhesives, primers or additives
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09) if change in material, heat strengthening process or if
thickness is reduced
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12) / Retention of junction box on mounting surface (MQT 14.1) (can be
omitted for glass with identical UV cut-off)
• Damp heat test (MQT 13) if non-glass or if surface treatment is added/changed (inside or
outside)
• Static mechanical load test (MQT 16) (can be omitted for different inside and outside
surface treatments that do not impair mechanical strength)
• Hail test (MQT 17) (can be omitted for different surface treatment on the inside)

Repeat for IEC 61730:
• Insulation thickness test (MST 04) if non-glass
• Cut susceptibility test (MST 12) if non-glass
• Impulse voltage test (MST 14) if reduced thickness or if change in material
• Temperature test (MST 21) if non-glass and change in material
• Ignitability test (MST 24) if non-glass
• Module breakage test (MST 32) (can be omitted for different surface treatments that do
not impair mechanical strength)
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes cemented joint
(not for reduction of thickness, not for different outer surface treatment and not for change
in glass strengthening process)
• Materials creep test (MST 37) (not for reduction of thickness and not for different outside
surface treatment)
• Sequence B if non-glass
• Sequence B1 if design qualified for pollution degree 1 (not for reduction of thickness, not
for different surface treatment and not for change in glass strengthening process)
For increased thickness, the Materials creep test (MST 37) is required.
4.2.2 Modification to encapsulation system
For the following modifications:
• Different material
• Different type or change in amount of additive or different chemical composition of
encapsulant
• Different manufacturer of encapsulant
• Different encapsulation process (e.g. curing degree, temperature/pressure profile)
• Reduction in thickness of total encapsulation by more than 20 % prior to processing
)
(thickness can also be expressed in density, e.g. in g/cm
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12)
• Damp heat test (MQT 13)
• Hail test (MQT 17) if frontsheet is polymeric
Repeat for IEC 61730:
• Cut susceptibility test (MST 12) if frontsheet or backsheet is polymeric
• Impulse voltage test (MST 14) if reduced thickness or if change in material
• Module breakage test (MST 32) if material composition changes
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes encapsulant as
a part of a qualified cemented joint
• Materials creep test (MST 37)
• Sequence B (only for different material or reduction in thickness)
• Sequence B1 if design qualified for pollution degree 1

– 10 – IEC TS 62915:2018 © IEC 2018
4.2.3 Modification to cell technology
For the following modifications:
• Metallization material composition (e.g. paste)
• Change in busbar metallization area by more than 20 %
• Change in number of busbars
• Change in anti-reflective coating
• Semiconductor layer material
• Change in crystallization process (e.g. mono- vs. poly-crystalline)
• Change of manufacturing site of the solar cells not under the same quality management
system
• Use of cells from a different manufacturer
• Change in nominal cell thickness greater than 10 %
• Different size of cell or use of cut cells (e.g. halved)
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• Thermal cycling test, 200 cycles (MQT 11)
• Damp heat test (MQT 13) (may be omitted if outer surface of cell is chemically identical
(metallization and AR coating))
• Static mechanical load test (MQT 16) for reduction of cell thickness only
Repeat for IEC 61730:
• Temperature test (MST 21)
• Reverse current overload test (MST 26)
4.2.4 Modification to cell and string interconnect material or technique
For the following modifications:
• Different material (e.g. alloy, chemistry and core)
• Change in mechanical properties by more than 10 % of tensile strength, yield strength and
elongation
• Change in thickness by more than 10 %
• Change in (total) cross-section of interconnect material (e.g., more busbars / more
busbars with less width)
• Different bonding technique
• Change in the number of interconnect or bonding points or decrease in bonding area per
contact point
• Different length of interconnect material between last bond on one cell and first bond on
the adjacent cell
• Different solder material, flux or conductive adhesive
• Change in insulation tape (thickness, material, manufacturer)
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09) for changes in bonding technique, interconnect
material, solder material, flux or conductive adhesive
• Thermal cycling test, 200 cycles (MQT 11)

• Damp heat test (MQT 13) for changes in material
Repeat for IEC 61730:
• Reverse current overload test (MST 26)
4.2.5 Modification to backsheet
A change from glass to non-glass or vice-versa requires a full qualification.
For the following modifications:
• Different material, i.e. any change in specification of the material or any of its layers
• Glass: reduction of thickness by more than 10 %; non-glass: change of thickness by more
than 20 % of any one of the individual layers (while maintaining the required minimum
distance through insulation)
• For glass, if there is a reduction in the strengthening process (e.g. retest if change is from
tempered to heat strengthened or annealed glass)
• Different surface treatments (inside or outside)
• Change of amount of adhesives, primers or other additives
• Addition or removal of adhesives, primers or additives
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09) for glass if change in heat strengthening process or if
thickness is reduced
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12) / Retention of junction box on mounting surface (MQT 14.1) (can be
omitted for glass with identical UV cut-off; not for glass change). MQT 14.1 can be omitted
if junction box is mounted on frontsheet.
• Damp heat test (MQT 13) if non-glass or if surface treatment is added/changed (inside or
outside).
• Static mechanical load test (MQT 16) if glass (including change in manufacturer) or if
mounting depends on adhesion to backsheet
• Hail test (MQT 17) if rigidity depends on backsheet
Repeat for IEC 61730:
• Insulation thickness test (MST 04) if non-glass
• Cut susceptibility test (MST 12) if non-glass
• Impulse voltage test (MST 14) if reduced thickness or if change in material
• Temperature test (MST 21) if non-glass and if change in material
• Ignitability test (MST 24) if non-glass
• Module breakage test (MST 32) if glass (can be omitted for different surface treatments
that do not impair mechanical strength)
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes cemented joint
and if backsheet is part of it
• Materials creep test (MST 37) (not for reduction of thickness and not for different outside
surface treatment)
• Sequence B if non-glass
• Sequence B1 if design qualified for pollution degree 1
For increased thickness, the Materials creep test (MST 37) is required.

– 12 – IEC TS 62915:2018 © IEC 2018
Additionally, in case of colour change of backsheet potentially resulting in higher PV module
operating temperatures, consider repetition of the Temperature test (MST 21), if applicable.
4.2.6 Modification to electrical termination
Components for electrical terminations such as junction box, cables and connectors shall
meet the relevant IEC standards referenced in IEC 61730-1. Their combination with other
components and materials shall be tested either on PV module level or on component level. A
change in component combination may result in the following PV module tests in addition to
tests listed in the relevant component standards.
For the following modifications:
• Different material
• Different design (e.g., different dimensions, changed positions, number of junction boxes)
• Different potting material
• Different method of mechanical attachment / securement (e.g. adhesive change)
• Different method of electrical attachment (e.g. solder, crimping, brazing, etc.)
Repeat for IEC 61215:
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12) / Robustness of terminations test (MQT 14.1 and 14.2) (UV
preconditioning test can be omitted for change in potting material or in case junction box is
not directly exposed to sunlight; Test of cord anchorage (MQT 14.2) can be omitted for
change in mechanical attachment of junction box; Retention of junction box on mounting
surface (MQT 14.1) can be omitted for change in electrical attachment of cables)
• Thermal cycling test, 200 cycles (MQT 11) only for change in electrical attachment
• Damp heat test (MQT 13)
• Bypass diode thermal test (MQT 18) (not required for change of any attachment)
Repeat for IEC 61730:
• Accessibility test (MST 11)
• Temperature test (MST 21) if change in potting material or adhesive
• Ignitability test (MST 24) only for change of adhesive
• Reverse current overload test (MST 26) (not for change of adhesive)
• Screw connections test (MST 33) if applicable
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes cemented joint
(only for mechanical attachment of junction box)
• Materials creep test (MST 37) only for change of adhesive or for increased weight of
electrical termination
• Sequence B only for change of adhesive
• Sequence B1 if design qualified for pollution degree 1
4.2.7 Modification to bypass diode
For bypass diodes mounted within the junction box, requirements of IEC 62790 need to be
fulfilled.
For bypass diodes not mounted within the junction box, the following applies:
For the following modifications:

• Lower rating of diode current or diode junction temperature
• Different number of bypass diodes per PV module
• Different type of bypass diode
• Different manufacturer of bypass diode
• Different mounting method (physical configuration, soldering material, bonding process,
soldering temperature or process)
Repeat for IEC 61215:
• Thermal cycling test, 200 cycles (MQT 11) only for different mounting method
• Bypass diode thermal test (MQT 18)
Repeat for IEC 61730:
• Reverse current overload test (MST 26) only for different mounting method
4.2.8 Modification to electrical circuitry
For the following modifications:
• Modifications to the interconnection circuitry (e.g. more cells per bypass diode or rerouting
of output leads)
• Reconfiguration of PV module operating voltage/current (e.g. serial/parallel connection of
cells)
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09) only if more cells per bypass diode
• Thermal cycling test, 200 cycles (MQT 11) if there are internal conductors behind the cells
• Bypass diode thermal test (MQT 18) if the short circuit current increases by >10 %
Repeat for IEC 61730:
• Insulation thickness test (MST 04) for rerouting of output leads
• Reverse current overload test (MST 26) (only for increase in PV module operating
voltage/current by 10 % or more)
4.2.9 Modification to edge sealing
For the following modifications:
• Different material
• Different thickness or width
Repeat for IEC 61215:
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12) if edge sealing is outer enclosure
• Damp heat test (MQT 13)
Repeat for IEC 61730:
• Impulse voltage test (MST 14)
• Ignitability test (MST 24) (not for different thickness or width)
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes cemented joint
• Sequence B (not for different thickness or width)

– 14 – IEC TS 62915:2018 © IEC 2018
• Sequence B1 if design qualified for pollution degree 1
4.2.10 Modification to frame and/or mounting structure
For the following modifications:
• Shape and/or cross-section of frame
• Reduction of surface area in contact between laminate and frame per linear dimension
• Different material including adhesive or mounting material
• Different mounting method (as defined in installation manual)
• Change in frame corner design
• Change in frame adhesive
• Change from framed to frameless PV module or vice versa
Repeat for IEC 61215:
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12) if mounting relies on adhesive or polymeric framing material
• Thermal cycling test, 200 cycles (MQT 11) if mounting relies on adhesive or polymeric
framing material
• Damp heat test (MQT 13) if mounting relies on adhesive or polymeric framing material or if
change from framed to frameless PV module or vice versa
• Static mechanical load test (MQT 16)
• Hail test (MQT 17) if polymeric frame / frontsheet or if change from framed to frameless
PV module
Repeat for IEC 61730:
• Continuity test of equipotential bonding (MST 13) if change in method of assembly (can be
omitted if change in adhesive)
• Ignitability test (MST 24) for polymeric frames
• Module breakage test (MST 32)
• Screw connections test (MST 33) if applicable
• Material creep test (MST 37) if creep is not prevented by frame or other support anymore
• Sequence B for polymeric frames
In case of change of frame manufacturer or mounting system manufacturer (same material
specifications and design) no tests are required.
4.2.11 Change in PV module size
For increase by more than 20 % of length, width or area
Repeat for IEC 61215:
• Thermal cycling test, 200 cycles (MQT 11)
• Damp heat test (MQT 13)
• Static mechanical load test (MQT 16)
• Hail test (MQT 17) if non-tempered glass or if non-glass
Repeat for IEC 61730:
• Module breakage test (MST 32)

4.2.12 Higher or lower output power (by 10 % or more) with the identical design and
size and using the identical cell process
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• Thermal cycling test, 200 cycles (MQT 11) if short-circuit current is increased by more
than 10 %
• Bypass diode thermal test (MQT 18) if short-circuit current is increased by more than 10 %
For performance at STC (MQT 06.1) see 4.1.
Repeat for IEC 61730:
• Reverse current overload test (MST 26)
4.2.13 Increase of over-current protection rating
Repeat for IEC 61730:
• Continuity test of equipotential bonding (MST 13)
• Reverse current overload test (MST 26)
4.2.14 Increase of system voltage
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12)
• Thermal cycling test, 200 cycles (MQT 11)
• Damp heat test (MQT 13)
Repeat for IEC 61730:
• Insulation thickness test (MST 04)
• Accessibility test (MST 11)
• Cut susceptibility test (MST 12) if non-glass
• Continuity test of equipotential bonding (MST 13)
• Impulse voltage test (MST 14)
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes cemented joint
• Sequence B
4.2.15 Change in cell fixing tape
For the following modifications:
• Different material
• Different manufacturer
Repeat for IEC 61215:
• Humidity freeze test (MQT 12)
4.3 Test programs for thin-film PV modules
NOTE See Table A.2 for a summary of the retest requirements for thin-film PV modules.

– 16 – IEC TS 62915:2018 © IEC 2018
4.3.1 Modification to frontsheet
A change from glass to non-glass or vice-versa requires a full qualification.
For the following modifications:
• Different material, i.e. any change in specification of the material or any of its layers
• Glass: reduction of thickness by more than 10 %; non-glass: change of thickness by more
than 20 % of any one of the individual layers (while maintaining the required minimum
distance through insulation)
• For glass, if there is a reduction in the strengthening process (for example retest if change
is from tempered glass to heat strengthened or annealed)
• Different surface treatment, e.g. any coating on frontsheet (inside or outside)
• Change of amount of adhesives, primers or other additives
• Addition or removal of adhesives, primers or additives
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09) if change in material, heat strengthening process or if
thickness is reduced
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12) / Retention of junction box on mounting surface (MQT 14.1) (can be
omitted for glass with identical UV cut-off)
• Damp heat test (MQT 13) if non-glass or if cell material is deposited on glass or if surface
treatment is added/changed (inside or outside)
• Static mechanical load test (MQT 16) (can be omitted for different inside and outside
surface treatment that do not impair mechanical strength)
• Hail test (MQT 17) (can be omitted for different surface treatment on the inside)
Repeat for IEC 61730:
• Insulation thickness test (MST 04) if non-glass
• Cut susceptibility test (MST 12) if non-glass
• Impulse voltage test (MST 14) if reduced thickness or if change in material
• Temperature test (MST 21) if non-glass and change in material
• Ignitability test (MST 24) if non-glass
• Module breakage test (MST 32) (can be omitted for different surface treatments that do
not impair mechanical strength)
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes cemented joint
(not for reduction of thickness, not for different outer surface treatment and not for change
in glass strengthening process)
• Materials creep test (MST 37) (not for reduction of thickness and not for different outside
surface treatment)
• Sequence B if non-glass
• Sequence B1 if design qualified for pollution degree 1 (not for reduction of thickness, not
for different surface treatment and not for change in glass strengthening process)
For increased thickness, the Materials creep test (MST 37) is required.
4.3.2 Modification to encapsulation system
For the following modifications:

• Different material
• Different type or change in amount of additive or different chemical composition of
encapsulant
• Different manufacturer of encapsulant
• Different encapsulation process (e.g. curing degree, temperature/pressure profile)
• Reduction in thickness of total encapsulation by more than 20 % prior to processing
(thickness can also be expressed in density, e.g. in g/cm )
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12)
• Damp heat test (MQT 13)
• Hail test (MQT 17) if frontsheet is polymeric
Repeat for IEC 61730:
• Cut susceptibility test (MST 12) if frontsheet or backsheet is polymeric
• Impulse voltage test (MST 14) if reduced thickness or if change in material
• Module breakage test (MST 32) if material composition changes
• Peel test (MST 35) or Lap shear strength test (MST 36) if design includes encapsulant as
a part of a qualified cemented joint
• Materials creep test (MST 37)
• Sequence B (only for different material or reduction in thickness)
• Sequence B1 if design qualified for pollution degree 1
4.3.3 Modification to front contact (e. g. TCO)
For the following modifications:
• Different manufacturer
• Different material, reduction in material purity
• Change in production process
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• UV preconditioning test (MQT 10) / Thermal cycling test, 50 cycles (MQT 11) / Humidity
freeze test (MQT 12)
• Damp heat test (MQT 13)
Repeat for IEC 61730:
• Impulse voltage test (MST 14)
• Reverse current overload test (MST 26)
The use of process gases or targets from different suppliers, but same minimum purities does
not require retesting.
4.3.4 Modification to cell technology
For the following modifications:

– 18 – IEC TS 62915:2018 © IEC 2018
• Change in cell structure (modification of any layer / additional layer / change of overall cell
thickness > 10 %)
• Reduction in process gas purity (including mixing ratios)
• Change in source or target material or reduction in target purity
• Change in doping material composition
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• Damp heat test (MQT 13)
Repeat for IEC 61730:
• Temperature test (MST 21)
• Reverse current overload test (MST 26)
A change in the semiconductor material/technology requires a full qualification.
4.3.5 Modification to cell layout
For the following modifications:
• Change in number of cells (given that the output power increases by > 10 %)
• Change in serial/parallel connection
• Change in number of cross-scribes
• Change in cell width > 10 %
• Change in patterning technology (e.g. laser vs. mechanical)
• Increase in number of cells per bypass diode
Repeat for IEC 61215:
• Hot-spot endurance test (MQT 09)
• Bypass diode thermal test (MQT 18) if the short-circuit current increases by > 10 %
Repeat for IEC 61730:
• Reverse current overload test (MST 26)
4.3.6
...