IEC TS 63126:2025

IEC TS 63126 ®
Edition 2.0 2025-10
TECHNICAL
SPECIFICATION
REDLINE VERSION
Guidelines for qualifying PV modules, components and materials for operation
at high temperatures
ICS 27.160 ISBN 978-2-8327-0787-6
IEC TS 63216:2025-10 RLV(en)
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CONTENTS
FOREWORD . 3
INTRODUCTION . 1
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
3.1 Terms and definitions. 9
3.2 Sheet-related definitions . 11
4 Modifications to IEC 61215-2 the IEC 61215 series . 12
4.1 General . 12
4.2 Hot-spot endurance test (MQT 09) . 12
4.3 UV preconditioning test (MQT 10) . 12
4.4 Thermal cycling test (MQT 11) . 12
4.5 Bypass diode testing (MQT 18) . 13
5 Modifications to the IEC 61730 series . 13
5.1 IEC 61730-1 . 13
5.2 IEC 61730-2 . 14
5.2.1 General . 14
5.2.2 Hot-spot endurance test (MST 22) . 14
5.2.3 Bypass diode thermal test (MST 25) . 14
5.2.4 Materials creep test (MST 37) . 14
5.2.5 Thermal cycling test (MST 51) . 14
5.2.6 UV test (MST 54) . 14
5.2.7 Dry heat conditioning (MST 56) . 14
6 Modifications to component standards . 14
6.1 Polymeric packaging material testing requirements . 14
6.1.1 Test procedures for optical durability of polymer packaging materials . 14
6.1.2 Polymeric backsheets and frontsheets . 14
6.2 Junction boxes according to IEC 62790 . 16
6.3 Connectors for DC application in photovoltaic systems according to
IEC 62852 . 16
6.4 Electric cables for photovoltaic systems with a voltage rating of 1,5 kV DC
according to IEC 62930 . 17
7 Test modification summary . 18
8 Reporting . 20
Annex A (informative) Determination of temperature level . 21
A.1 General . 21
A.2 Modelling . 21
th
A.3 98 percentile temperatures (T T ) . 25
98th 98
A.4 Guidance on module temperature for locations worldwide . 28
A.5 Guidance to system design specific modifications . 31
A.6 Site specific concerns . 32
A.7 Guidance on module temperature for several locations . 26
Bibliography . 36

Figure A.1 – Open-rack or rack-mounted configuration (open) . 23
Figure A.2 – Close-roof configuration . 23
Figure A.3 – Insulated-backsheet configuration . 24
Figure A.4 – Variety of standoff distances [3] . 24
Figure A.5 – Exponential decay fit to data from Fuentes [11], Formula (A.2) . 25
Figure A.6 – Histogram and cumulative distribution function (CDF) of module
temperature for Riyadh, Saudi Arabia . 27
Figure A.7 – Time series from the temperature model for Riyadh, Saudi Arabia . 28
th
Figure A.8 – Minimum standoff distance for a module estimated to achieve a 98
percentile temperature of 70 °C and to qualify for Level 0 . 30
th
Figure A.9 – Minimum standoff distance for a module estimated to achieve a 98
percentile temperature of 80 °C and to qualify for Level 1 or Level 0 . 30
th
Figure A.10 – 98 percentile temperature for an open-rack, or thermally unrestricted,
glass superstrate, polymer backsheet module . 33
th
Figure A.11 – 98 percentile temperature for a close-roof mounted glass superstrate,
polymer glass backsheet module . 34
th
Figure A.12 – 98 percentile temperature for insulated-back glass superstrate,
polymer backsheet module . 35

Table 1 – UV and thermal exposure conditions for backsheets and frontsheets. 16
Table 2 – Test modification summary . 18
Table 3 – Parameters for module temperature model according to Formula (A.1) . 22

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Guidelines for qualifying PV modules, components
and materials for operation at high temperatures

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes made
to the previous edition IEC TS 63126:2020. A vertical bar appears in the margin wherever a
change has been made. Additions are in green text, deletions are in strikethrough red text.

IEC TS 63126 has been prepared by IEC technical committee 82: Solar photovoltaic energy
systems. It is a Technical Specification.
This second edition cancels and replaces the first edition published in 2020. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition.
a) Updated the Introduction and Scope to clarify the applicability of this document.
b) Defined "Level 0" as that qualified for in the IEC 61730 series and the IEC 61215 series.
c) For the purposes of minimizing testing needs, it is explicitly stated if a test or sequence is
passed for a higher Level that it passes for lower levels too.
d) Backsheet weathering was changed to match what is in IEC 62788-2-1. For all three levels,
the test condition is A3 with 4 000 h on the front side and 2 000 h on the back side.
e) Frontsheet weathering was kept at 4 000 h under A4 or A5 exposure conditions but options
for exposure using A3 for longer times or using A3 with a dark insulator on the back are
described.
f) The UV test of MST 54 is now only applied to the front side exposure in sequence B of
IEC 61730. Previously, it was modified as part of IEC 61215 MQT 10 which is an equivalent
exposure to MST 54.
g) Modified the backsheet testing for longer duration for frontside exposure and for the use of
A3 for all levels.
h) For IEC 62788-7-1 for the optical transmittance of encapsulants, a longer exposure using
the A3 condition is outlined in this document, but the original A4 and A5 options were not
modified. A third option to insulate the backside with a dark light absorbing material to
achieve elevated temperatures was also added.
i) The higher thermal cycling (TC) testing for Level 1 and Level 2 will only apply to the 200 TC
leg of IEC 61730 and IEC 61215.
j) For sequence C of IEC 61730, the UV preconditioning test (MST 54) will no longer be
modified as the 50 TC of this sequence is not modified.
k) For sequence B of IEC 61730, the higher temperature for the UV exposure (MST 54) dose
will only be applied to the frontsheet of a module. The backsheet exposure will not be
changed.
l) Relative to IEC 61215, the high temperature modification of the TC test only applies to
sequence D and MQT 10 (UV preconditioning) is not modified, i.e. sequence C of IEC 61215
is not changed.
m) Improved method for estimating the T temperature. This includes a method utilizing an
effective standoff distance for quick estimate of the system temperature. Or it can be used
to estimate a minimum standoff distance for a given geographic location.
n) The testing for the junction box standard, IEC 62790 was clarified to explicitly state the
upper ambient temperature for testing. Here ambient testing temperature for Level 2 was
also reduced from 105 °C to 100 °C.
o) Changed the modifications to IEC 62852 to specify the ambient testing temperature instead
of the ULT. Ambient test temperatures of 85 °C, 90 °C and 100 °C are used for Level 0, 1,
and 2, respectively.
The text of this Technical Specification is based on the following documents:
Draft Report on voting
82/2401/DTS 82/2472/RVDTS
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Specification is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
INTRODUCTION
Originally, the IEC 61215 series, the IEC 61730 series, IEC 62790 and IEC 62852 were
considered suitable for an environmental temperature range of at least −40 °C to +40 °C and
th
for. For open-rack modules operating in such conditions a 98 -percentile module operational
operating temperature of 70 °C or less applies is obtained. This environmental temperature
range encompasses many locations and installation styles in these locations. As an example,
it has been determined that thermally unrestricted, or open-rack-style structures, in most cases
th
do not result in 98 -percentile module operational operating temperatures exceeding 70 °C and,
as such, the originating standards are suitable as written. Cases where the module operating
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temperatures exceeding exceeds 70 °C, on the other hand, at the 98 percentile typically will
occur with roof-parallel or building-integrated roof top applications in climates with local
environmental temperatures that exceed 40 °C.
This document is written for two purposes: to provide modified testing conditions for modules
that will be deployed in climates that either have a higher environmental air temperature than
40 °C and/or for module installation methods that restrict cooling, or both, resulting which are
likely to result in higher operational operating temperatures than anticipated in the originating
standards. This work will also aid in providing an alternative definition of "rack mount" in the
context of the IEC 61215 series and IEC 61730 series. This term was initially used as a
placeholder to restrict the scope of PV module type testing for those installation styles that
permit open and unrestricted cooling from all surfaces of a PV module. Now that the testing has
matured, there is a desire to refine definitions for the range of applicability of these standards.
This document is intended to be used as an intermediate step to define defines high
temperature environment use requirements but does not include applications designed to
combine photovoltaic and thermal energy applications. These requirements are planned to be
being refined and in part incorporated into other standards in the future. It is not necessarily
cost effective for module materials to comply with Level 1 or Level 2 requirements defined in
th
this document, unless the module temperature is expected to exceed 70 °C at the 98
percentile. Primarily, this will only be necessary in building applied applications in hot climates.
Vertical building facades are not likely to operate at these high temperatures because of
reduced in plane irradiance and good free convection on the outer surface. Module materials
capable of temperature Level 1 or temperature Level 2 are expected to impose higher
expectations of endurance and cost than normal modules.
onent standard IEC 62930 is considered to be adequate for modules operating at high
Comp
temperatures without modification due to requiring cable to have a 120 °C or greater thermal
endurance at a 20 000 h correlation lifetime. A guide for cable correction factors at higher cable
ambient temperatures is given in IEC 62930:2017, Table A.4. Similarly, IEC 62979 [1] is
considered adequate for bypass diode thermal runaway determination due to testing
temperatures of 90 °C for roof-mounted modules and 75 °C for "rack mounted" modules.
Similar to electric cables, IEC 61730-1 requires a relative thermal index (RTI), thermal index
(TI), or relative thermal endurance (RTE) of 90 °C or larger. A module operating in an
th
environment and installation style resulting in a 98 percentile temperature of 70 °C requires
an RTI, TI, or RTE safety factor of +20 °C to establish a 25-year lifetime when the polymer has
a minimum activation energy of 46 kJ/mol and the correlation lifetime is 20 000 h. This work
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approximately applies that safety factor of +20 °C for polymer RTI, TI, or RTE when the 98
percentile operating temperature is above 70 °C.
_____________
Numbered in square brackets refer to the Bibliography.
Finally, Data from PV modules in hot climates and modelling were used to understand operating
temperatures and resulted in two categories of high temperature operation, temperature Level 1
and temperature Level 2. These categories are defined within this document and it is relevant
to indicate that Level 2 temperatures were not found in field data, but may can result from
insulated substrate modules on pitched roofs facing the sun when ambient air temperature
exceeds 40 °C. This may can be most consistent with building-integrated PV module roofs and,
to allow for this possibility, the temperature Level 2 category remains in this document.
In Annex A, methods are given for estimating when a particular system design will need higher
levels of qualification. Short of actual measurement at a particular site, one cannot precisely
th
estimate the 98 percentile temperature. However, the suggested methods give a rough
approximation of when Level 1 and Level 2 qualification are likely to be needed.

1 Scope
This document defines additional testing requirements for photovoltaic (PV) modules deployed
under conditions leading to higher module temperature which are beyond the scope of
IEC 61215-1 and IEC 61730-1 and the relevant component standards, IEC 62788-1-7,
IEC 62788-2-1, IEC 62790 and IEC 62852. The testing conditions specified in IEC 61215-2 and
IEC 61730-2 (and the relevant component standards IEC 62788-1-7, IEC 62788-2-1, IEC 62790
and IEC 62852) assumed that these standards are applicable for module deployment where the
th
98 percentile temperature (T T ), that is the temperature that a module would be expected
98th 98
to equal or exceed for 175,2 h per year, is less than 70 °C.
NOTE 175,2 h represents 2 % of a total year as some thermal failure modes are a function of time at temperature
and not sensitive to day-only or night-only exposure.
Hybrid PV and thermal systems are out of scope of this document. Guidance on the selection
of meteorological data for use in estimating T is outside the scope of this document and it is
important to give it careful consideration. Annex A provides a method for estimating the
temperature rating for PV modules without installation- or location-specific verification. With
this, suitable installation practices and long-term durability testing can be prescribed. More
accurate prescription of the temperature rating including local assessment and verification is
outside the scope of this document. The effects of climate change are uncertain and not in the
scope of this document. The intent of this specification is to address issues with higher
temperatures but not for extended durability beyond that assessed in the IEC 61215 series or
IEC 61730 series.
This document defines two temperature regimes, temperature Level 1 and temperature Level 2,
which were designed considering deployment in environments with mounting configurations
such that the T T is less than or equal to 80 °C for temperature Level 1, and less than or
98th 98
equal to 90 °C for temperature Level 2. This document provides recommended additional
testing conditions within the IEC 61215 series, IEC 61730 series, IEC 62788-1-7,
IEC 62788-2-1, IEC 62790 and IEC 62852 for module operation in temperature Levels 1 and 2.
Successfully passing a higher Level for a test, sequence of tests, or complete testing for a
higher Level is an implied passing of the relevant lower-Level testing. For example, passing
200 thermal cycles for Level 2 is considered passing Level 0 and Level 1 for 200 thermal cycles.
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 61215-2:20162021, 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, Photovoltaic (PV) module safety qualification - Part 1: Requirements for
construction
IEC 61730-2, Photovoltaic (PV) module safety qualification - Part 2: Requirements for testing
IEC TS 61836, Solar photovoltaic energy systems - Terms, definitions and symbols
IEC 62788-1-7, Measurement procedures for materials used in photovoltaic modules - Part 1-7:
Encapsulants - Test procedure of optical durability
IEC TS 62788-2:2017, Measurement procedures for materials used in photovoltaic modules –
Part 2: Polymeric materials – Frontsheets and backsheets
IEC 62788-2-1, Measurement procedures for materials used in photovoltaic modules – Part 2-1:
Polymeric materials - Frontsheets and backsheets - Safety requirements
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 62790, Junction boxes for photovoltaic modules - Safety requirements and tests
IEC 62852, Connectors for DC-application in photovoltaic systems - Safety requirements and
tests
IEC 62930:2017, Electric cables for photovoltaic systems with a voltage rating of 1,5 kV DC
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC TS 61836, the
IEC 61730 series, the IEC 61215 series and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Terms and definitions
3.1.1
environmental temperature
air temperature defined in degrees Celsius for the geographic installation location as measured
and documented by meteorological services for this geographic location
Note 1 to entry: The environmental temperature is typically measured 1 m above ground. PV modules deployed
closer to the ground may can experience higher ambient temperatures than this quoted environmental temperature.
3.1.2
ambient temperature
average temperature of air or another medium in the vicinity of the equipment
Note 1 to entry: During the measurement of the ambient temperature the measuring instrument/probe should be
shielded from draughts and radiant heating.
Note 2 to entry: Ambient temperature is often called operating temperature or operational temperature.
temperature of the air in free air conditions at such a distance from the specimen that the effect
of the dissipation is negligible
Note 1 to entry: Ambient temperature is often called operating temperature or operational temperature.
[SOURCE: IEC 60068-1:2013, 3.9, modified – The definition has been expanded and Note 1 to
entry has been replaced by a new note to entry.]
3.1.3
module operational operating temperature
temperature representative of the PV module – usually of the junction of the solar cells within
the module. This temperature may be measured by means of a temperature sensor or via the
equivalent cell temperature technique according to IEC 60904-5
3.1.4
th
98 -percentile module operating temperature
T
th
when temperature data from a varying temperature process are placed into rank order, the 98 -
percentile temperature represents a temperature that is larger than 98 percent of remaining
temperatures and is exactly met or exceeded only 2 % of the time
temperature at which the module operating temperature is operating below more than 98 % of
the time when deployed in a PV system
ᵗʰ
Note 1 to entry: The 98 -percentile temperature is to be determined from data taken at hourly, or more frequent,
ᵗʰ
measurements. For a standard year, the 98 -percentile temperature would be met or exceeded for 175,2 h.
3.1.5
rated module operating temperature
]
[T
98 max
th
maximum 98 -percentile module operating temperature at which the module is rated to be
deployed at the rated temperature on the nameplate
3.1.6
standoff distance
distance between the frame (or the bottom of the module) and the roof or mounting structure
3.1.7
temperature Level 0
temperature used to categorize test modifications, which applies for PV modules where [T ]
98 max
is 70 °C and all other tests are the defaults for their respected tests (e.g. the IEC 61730 series
and the IEC 61215 series)
3.1.8
temperature Level 1
temperature is used to categorize test modifications and, which applies for PV modules whose
th
98 -percentile temperature falls into the range greater than 70 °C but less than or equal to
80 °C
3.1.9
temperature Level 2
temperature is used to categorize test modifications and, which applies for PV modules whose
th
98 -percentile temperature falls into the range greater than 80 °C but less than or equal to
90 °C
3.1.10
upper limiting temperature
ULT
maximum temperature in the connector, as outcome (sum) of the ambient temperature and the
temperature rise due to current flow, at which the connector is intended to be still operable
Note 1 to entry: At ambient temperature equal to ULT, the available temperature rise due to current flow is zero,
thus the current carrying capacity of the connector is zero.
[SOURCE: IEC 61984:2008, 3.15, modified – Note 2 has been deleted.]
3.1.11
lower limiting temperature
LLT
minimum temperature of a connector as defined by the manufacturer, in which the connector is
intended to operate
3.2 Sheet-related definitions
3.2.1
air-side
side of the front- or backsheet oriented towards the outside of the PV module, i.e., away from
the cells
3.2.2
backsheet
(combination of) outer layer(s) of the PV module, located as substrate on the back of the PV
module and providing protection of the inner components of the PV module from external
stresses and weather elements, as well as providing electrical insulation
3.2.3
frontsheet
(combination of) outer layer(s) of the PV module designed for prolonged exposure to direct
sunlight (> 300 W/m ) and providing protection of the inner components of the PV module from
external stresses and weather elements, as well as providing electrical insulation
3.2.4
sun-facing side
air-side of a frontsheet and inner side of a backsheet
3.2.5
FBST
front- or backsheet safety test in accordance with IEC 62788-2-1
3.2.6
distance through insulation
t
DTI
thickness of relied-upon insulation (RUI) after the lamination protrusion test, with the minimum
allowable value defined by the rated system voltage
3.2.7
rated system voltage

V
sys

max
maximum system voltage for which a module is rated
3.2.8
relied-upon insulation
RUI
solid insulation system providing protection against electric shock in the final application, with
material's requirements for thermal endurance and resistance against environmental stress
factors
Note 1 to entry: Thin films used as polymeric front- or backsheet can consist of RUI plus additional layers that have
other functions, for example they protect the polymeric materials from UV radiation (see Table 1).
4 Modifications to IEC 61215-2 the IEC 61215 series
4.1 General
The tests in 4.2 to 4.5 are based on changes to the test procedures in IEC 61215-2.
Initial and final tests including MQT 19.1 Stabilisation shall be applied without modification.
4.2 Hot-spot endurance test (MQT 09)
MQT 09 of IEC 61215-2:2016 shall be performed by increasing the temperature from
(50 ± 10) °C to (60 ± 10) °C for rating modules to temperature level 1 and to (70 ± 10) °C for
rating modules to temperature Level 2.
All bifacial modules shall be tested according to the provisions of Level 0. When tested for
Level 1 or Level 2, the irradiance shall be front side only at 1 000 W/m as would be used for a
monofacial module. For both monofacial and bifacial modules, MQT 09 of IEC 61215-2 shall be
performed by increasing the module temperature from (55 ± 15) °C to (65 ± 15) °C for rating
modules to temperature Level 1 and to (75 ± 15) °C for rating modules to temperature Level 2.
The surface of the module temperature away from the influence of hotspot shall, at all times,
be within these temperature ranges.
Getting the module temperature up to 65 °C or 75 °C can be difficult; therefore, the placement
of thermal insulation or a heating element on the back of the module can be used to achieve
these temperatures.
NOTE Prolonged product operation under hot spot conditions with temperatures in excess of temperature Level 1
or Level 2 conditions may can lead to premature degradation of module packaging materials.
4.3 UV preconditioning test (MQT 10)
MQT 10 of IEC 61215-2:2016 shall be performed with module temperature sensors reading
(70 ± 5) °C for rating modules to temperature level 1 and (80 ± 5) °C for rating modules to
temperature level 2. This change only affects the temperature sensor reading from (60 ± 5) °C
to the new, higher values.
No modification of this is made with respect to IEC 61215-2 but modifications are applied to
this when referred to IEC 61730-2 (MST 54) in 5.2.6.
4.4 Thermal cycling test (MQT 11)
MQT 11 of IEC 61215-2:2016 shall be performed with modification to the temperature setpoints
as indicated below leaving the dwell times and temperature ramp rates unchanged.
In sequence D of IEC 61215-1, MQT 11 shall be performed with modification to the temperature
setpoints as indicated below leaving the dwell times and temperature ramp rates unchanged.
Testing in sequence C is not required to be modified, but tests at higher temperatures may be
used in this sequence for convenience if desired.
The upper limit of the temperature cycling shall be increased from (85 ± 2) °C to (95 ± 2) °C for
rating modules to temperature Level 1 and to (105 ± 2) °C for rating modules to temperature
Level 2.
The upper limit of continuous current flow shall be changed from 80 °C to 90 °C for rating
modules to temperature Level 1 and to 100 °C for rating modules to temperature Level 2. The
temperature at which the current flow shall be reduced to less than 1 % of the measured STC
peak power current shall be changed from 80 °C to 90 °C for rating modules to temperature
Level 1 and to 100 °C for rating modules to temperature Level 2.
Subject the module(s) to cycling between measured module temperatures of (–40 ± 2) °C and
(95 ± 2) °C for rating modules to temperature Level 1 and (105 ± 2) °C for rating modules to
temperature Level 2.
4.5 Bypass diode testing (MQT 18)
MQT 18 of IEC 61215-2:2016 shall be performed at higher temperatures and higher current
levels using the changes specified below.
In IEC 61215-2:2021, 4.18.1.3 (a), the apparatus shall instead be capable of heating the module
to a temperature of (100 ± 5) °C for rating modules to temperature Level 1 and (110 ± 5) °C for
rating modules to temperature Level 2 rather than just to (90 ± 5) °C.
Additionally, the apparatus shall be capable of applying a current equal to 1,4 times the STC
short circuit current of the module under test for rating modules to temperature levels 1 and 2.
V shall be measured at (110 ± 5) °C for rating modules to temperature levels 1 and 2 and be
D5
added to the least squares fit data.
With respect to IEC 61215-2:2021, 4.18.1.4 (j), change the instructions to "heat the module to
(90 ± 5) °C for rating modules to temperature Level 1 and (100 ± 5) °C for rating modules to
temperature Level 2" instead of to (75 ± 5) °C for Level 0. The heat sink exception of
IEC 61215-2:2021, 4.18.1.4 (j), still applies, and the ambient of (43 ± 3) °C can still be used.
With respect to IEC 61215-2:2021, 4.18.1.4 (j), change the instructions to "for rating at
temperature Level 1 and 2, apply a current to the module equal to 1,15 times the short circuit
current (1,15 × I ) ± 2 % of the module measured at STC" instead of testing at I ± 2 % for
sc sc
Level 0.
With respect to IEC 61215-2:2021, 4.18.1.4 (k), obtain T from V at T = 90 °C for rating
J D amb
modules to temperature Level 1 and 100 °C for rating modules to temperature Level 2 rather
than at 75 °C. The temperature curve in IEC 61215-2:2021, 4.18.1.4 (i), will need to be
determined at higher temperatures such that T is determined as an interpolation of the dataset.
J
This should at most require testing at 110 °C.
With respect to IEC 61215-2:2021, 4.18.1.4 (l), change the instructions to "for rating at
temperature levels 1 and 2, increase the applied current to 1,4 times the short-circuit current of
the module measured at STC while maintaining the module temperature at (90 ± 5) °C for rating
at temperature Level 1 and at (100 ± 5) °C for rating at temperature Level 2" instead of 1,25
times the short-circuit current at (75 ± 5) °C for Level 0.
NOTE For additional information regarding the chosen temperature and current levels for MQT 18, see [2].
5 Modifications to the IEC 61730 series
5.1 IEC 61730-1
Most of the tests called out in IEC 61730-1 are found in IEC 61730-2 and are covered in 5.2.
To be considered part of the relied upon insulation (RUI), which is needed for determining the
distance through insulation (t ), the relative thermal index (RTI), the thermal index (TI), or the
DTI
relative thermal endurance (RTE), construction requirement of IEC 61730-1 requires values of
at least 90 °C. Similarly, 90 °C is required for polymeric materials used for mechanical
functions. For safety qualification under this guideline, all these materials shall instead be
qualified to a minimum 100 °C RTE (RTI) or TI for temperature Level 1 modules and a minimum
of 110 °C for temperature Level 2 modules. All other requirements for the RUI remain as stated
in IEC 61730-1.
5.2 IEC 61730-2
5.2.1 General
The tests in 5.2.2 to 5.2.7 shall be conducted similarly to the test procedures in IEC 61730-2,
but with modifications as follows.
5.2.2 Hot-spot endurance test (MST 22)
This test is equivalent to MQT 09 in IEC 61215-2; follow the directions given in 4.2 for MQT 09.
NOTE Prolonged product operation under hot spot conditions with temperatures in excess of level higher than
allowed by Level 1 or Level 2 conditions may can lead to premature degradation of module packaging materials.
5.2.3 Bypass diode thermal test (MST 25)
This test is equivalent to MQT 18 in IEC 61215-2; follow the directions given in 4.5 for MQT 18.
5.2.4 Materials creep test (MST 37)
Temperature Level 1 modules shall continue to use (105100 ± 5) °C, but for temperature
Level 2 modules shall use (110 ± 5) °C.
5.2.5 Thermal cycling test (MST 51)
This test is equivalent to MQT 11 in IEC 61215-2, follow the directions given in 4.4 for MQT 11
and apply this only to sequence D in IEC 61215-2 and sequence E in IEC 61730-2. This is not
applied to sequence C of IEC 61215-2 or sequence C of IEC 61730-2.
5.2.6 UV test (MST 54)
This test is equivalent to MQT 10 in IEC 61215-2, so follow the directions given in 4.3 for
MQT 10. This test shall be performed with module temperature sensors reading (70 ± 5) °C for
rating modules to temperature Level 1 and (80 ± 5) °C for rating modules to temperature
Level 2. This change only affects the temperature sensor reading from (60 ± 5) °C to the new,
higher values.
5.2.7 Dry heat conditioning (MST 56)
Dry heat conditioning applies to pollution degree 1 constructions. Temperature Level 1 modules
shall continue to use (105100 ± 5) °C, but for temperature Level 2 modules shall use
(110 ± 5) °C.
6 Modifications to component standards
6.1 Polymeric packaging material testing requirements
6.1.1 Test procedures for optical durability of polymer packaging materials
Polymeric encapsulant materials evaluated to the requirements of IEC 62788-1-7 and intended
for use with high temperature modules at higher temperatures of Level 1 or Level 2 shall modify
the artificial accelerated weathering of temperature level 1 modules in one of three ways. Either
modify tests to temperature Level 1 by using the A4 condition in IEC TS 62788-7-2 and modify
the artificial accelerated weathering of temperature Level 2 modules shall be performed at the
A5 condition from this document by using the A5 condition and conduct these tests for 4 000 h.
The A3 condition may also be used for Level 1 with 6 000 h of exposure or for Level 2 with
8 000 h of exposure.
Lastly, one may put insulation on the backside of the test sample while it is in the environmental
chamber to cause it to reach a higher temperature. This insulation may also be coloured to
increase light absorption to increase the temperature. For Level 1, the A3 condition may be
used with backside insulation if the sample temperature will reach at least 75 °C. For Level 2,
the A3 or A4 exposure condition may be use with backside insulation if the sample temperature
will reach at least 85 °C. With the use of insulation on the backside of the samples, the
temperature of the sample shall be verified. This may be accomplished by the application of a
thermocouple sensor embe
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