IEC 61215-2:2016

IEC 61215-2 ®
Edition 1.0 2016-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Terrestrial photovoltaic (PV) modules – Design qualification and type approval –
Part 2: Test procedures
Modules photovoltaïques (PV) pour applications terrestres – Qualification de la
conception et homologation –
Partie 2: Procédures d'essai
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IEC 61215-2 ®
Edition 1.0 2016-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Terrestrial photovoltaic (PV) modules – Design qualification and type approval –

Part 2: Test procedures
Modules photovoltaïques (PV) pour applications terrestres – Qualification de la

conception et homologation –
Partie 2: Procédures d'essai
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-3205-7

– 2 – IEC 61215-2:2016 © IEC 2016
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope and object . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Test procedures . 10
4.1 Visual inspection (MQT 01) . 10
4.1.1 Purpose . 10
4.1.2 Procedure . 10
4.1.3 Requirements . 11
4.2 Maximum power determination (MQT 02) . 11
4.2.1 Purpose . 11
4.2.2 Apparatus . 11
4.2.3 Procedure . 11
4.3 Insulation test (MQT 03) . 11
4.3.1 Purpose . 11
4.3.2 Apparatus . 12
4.3.3 Test conditions . 12
4.3.4 Procedure . 12
4.3.5 Test requirements . 12
4.4 Measurement of temperature coefficients (MQT 04) . 12
4.5 Measurement of nominal module operating temperature (NMOT) (MQT 05) . 13
4.5.1 General . 13
4.5.2 Principle . 13
4.5.3 Test procedure . 13
4.6 Performance at STC and NMOT (MQT 06) . 14
4.6.1 Purpose . 14
4.6.2 Apparatus . 14
4.6.3 Procedure . 14
4.7 Performance at low irradiance (MQT 07) . 15
4.7.1 Purpose . 15
4.7.2 Apparatus . 15
4.7.3 Procedure . 15
4.8 Outdoor exposure test (MQT 08) . 15
4.8.1 Purpose . 15
4.8.2 Apparatus . 15
4.8.3 Procedure . 16
4.8.4 Final measurements . 16
4.8.5 Requirements . 16
4.9 Hot-spot endurance test (MQT 09) . 16
4.9.1 Purpose . 16
4.9.2 Hot-spot effect . 16
4.9.3 Classification of cell interconnection . 17
4.9.4 Apparatus . 19
4.9.5 Procedure . 19
4.9.6 Final measurements . 27

4.9.7 Requirements . 27
4.10 UV preconditioning test (MQT 10) . 27
4.10.1 Purpose . 27
4.10.2 Apparatus . 27
4.10.3 Procedure . 28
4.10.4 Final measurements . 28
4.10.5 Requirements . 28
4.11 Thermal cycling test (MQT 11) . 28
4.11.1 Purpose . 28
4.11.2 Apparatus . 28
4.11.3 Procedure . 29
4.11.4 Final measurements . 29
4.11.5 Requirements . 30
4.12 Humidity-freeze test (MQT 12) . 30
4.12.1 Purpose . 30
4.12.2 Apparatus . 30
4.12.3 Procedure . 30
4.12.4 Final measurements . 30
4.12.5 Requirements . 30
4.13 Damp heat test (MQT 13) . 31
4.13.1 Purpose . 31
4.13.2 Procedure . 31
4.13.3 Final measurements . 31
4.13.4 Requirements . 31
4.14 Robustness of terminations (MQT 14) . 32
4.14.1 Purpose . 32
4.14.2 Retention of junction box on mounting surface (MQT 14.1) . 32
4.14.3 Test of cord anchorage (MQT 14.2) . 32
4.15 Wet leakage current test (MQT 15) . 37
4.15.1 Purpose . 37
4.15.2 Apparatus . 37
4.15.3 Procedure . 37
4.15.4 Requirements . 38
4.16 Static mechanical load test (MQT 16) . 38
4.16.1 Purpose . 38
4.16.2 Apparatus . 38
4.16.3 Procedure . 39
4.16.4 Final measurements . 39
4.16.5 Requirements . 39
4.17 Hail test (MQT 17) . 39
4.17.1 Purpose . 39
4.17.2 Apparatus . 39
4.17.3 Procedure . 40
4.17.4 Final measurements . 41
4.17.5 Requirements . 41
4.18 Bypass diode testing (MQT 18) . 42
4.18.1 Bypass diode thermal test (MQT 18.1) . 42
4.18.2 Bypass diode functionality test (MQT 18.2) . 44
4.19 Stabilization (MQT 19) . 45

– 4 – IEC 61215-2:2016 © IEC 2016
4.19.1 General . 45
4.19.2 Criterion definition for stabilization . 45
4.19.3 Light induced stabilization procedures . 45
4.19.4 Other stabilization procedures . 46
4.19.5 Initial stabilization (MQT 19.1) . 47
4.19.6 Final stabilization (MQT 19.2) . 47

Figure 1 – Case S, series connection with optional bypass diode . 17
Figure 2 – Case PS, parallel-series connection with optional bypass diode . 18
Figure 3 – Case SP, series-parallel connection with optional bypass diode . 18
Figure 4 – Module I-V characteristics with different cells totally shadowed . 20
Figure 5 – Module I-V characteristics with the test cell shadowed at different levels . 21
Figure 6 – Hot-spot effect in a MLI thin-film module with serially connected cells . 22
Figure 7 – Module I-V characteristics with different cells totally shadowed where the
module design includes bypass diodes . 24
Figure 8 – Module I-V characteristics with the test cell shadowed at different levels
where the module design includes bypass diodes . 25
Figure 9 – Thermal cycling test – Temperature and applied current profile . 29
Figure 10 – Humidity-freeze cycle – Temperature and humidity profile . 31
Figure 11 – a) Typical arrangement for the cord anchorage pull test for component
testing from IEC 62790. b) Typical schematic arrangement for cord anchorage pull test
on PV module mounted junction box . 35
Figure 12 – Typical arrangement for torsion test . 36
Figure 13 – Hail-test equipment . 40
Figure 14 – Hail test impact locations: top for wafer/cell based technologies, bottom

for monolithic processed thin film technologies . 42
Figure 15 – Bypass diode thermal test . 43

Table 1 – Pull forces for cord anchorage test . 33
Table 2 – Values for torsion test . 34
Table 3 – Ice-ball masses and test velocities . 40
Table 4 – Impact locations . 41

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TERRESTRIAL PHOTOVOLTAIC (PV) MODULES –
DESIGN QUALIFICATION AND TYPE APPROVAL –

Part 2: Test procedures
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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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
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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 61215-2 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
This first edition of IEC 61215-2 cancels and replaces the second edition of IEC 61215 (2005)
and parts of the second edition of 61646 (2008) and constitutes a technical revision.
The main technical changes with regard to these previous editions are as follows:
This standard includes the testing procedures – formally Clause 10 – of the previous edition.
Revisions were made to subclauses NMOT (replaces NOCT – MQT 05), performance
measurements (MQT 06), robustness of terminations (MQT 14) and stabilization (MQT 19).

– 6 – IEC 61215-2:2016 © IEC 2016
The text of this standard is based on the following documents:
FDIS Report on voting
82/1048/FDIS 82/1076/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
A list of all parts in the IEC 61215 series, published under the general title Terrestrial
photovoltaic (PV) modules – Design qualification and type approval, can be found on the IEC
website.
This publication 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
the stability date indicated on the IEC web site 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.
The contents of the corrigendum of March 2018 have been included in this copy.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
INTRODUCTION
Whereas Part 1 of this standard series describes requirements (both in general and specific
with respect to device technology), the sub-parts of Part 1 define technology variations and
Part 2 defines a set of test procedures necessary for design qualification and type approval.
The test procedures described in Part 2 are valid for all device technologies.

– 8 – IEC 61215-2:2016 © IEC 2016
TERRESTRIAL PHOTOVOLTAIC (PV) MODULES –
DESIGN QUALIFICATION AND TYPE APPROVAL –

Part 2: Test procedures
1 Scope and object
This International Standard series lays down IEC requirements for the design qualification and
type approval of terrestrial photovoltaic modules suitable for long-term operation in general
open-air climates, as defined in IEC 60721-2-1. This part of IEC 61215 is intended to apply to
all terrestrial flat plate module materials such as crystalline silicon module types as well as
thin-film modules.
This standard does not apply to modules used with concentrated sunlight although it may be
utilized for low concentrator modules (1 to 3 suns). For low concentration modules, all tests
are performed using the current, voltage and power levels expected at the design
concentration.
The objective of this test sequence is to determine the electrical and thermal characteristics of
the module and to show, as far as possible within reasonable constraints of cost and time,
that the module is capable of withstanding prolonged exposure in general open-air climates.
The actual lifetime expectancy of modules so qualified will depend on their design, their
environment and the conditions under which they are operated.
2 Normative references
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.
IEC 60050, International Electrotechnical Vocabulary (available at
http://www.electropedia.org)
IEC 60068-1, Environmental testing – Part 1: General and guidance
IEC 60068-2-21, Environmental testing – Part 2-21: Tests – Test U: Robustness of
terminations and integral mounting devices
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady
state
IEC 60721-2-1, Classification of environmental conditions – Part 2-1: Environmental
conditions appearing in nature – Temperature and humidity
IEC 60891, Photovoltaic devices – Procedures for temperature and irradiance corrections to
measured I-V characteristics
IEC 60904-1, Photovoltaic devices – Part 1: Measurements of photovoltaic current-voltage
characteristics
IEC 60904-2, Photovoltaic devices – Part 2: Requirements for photovoltaic reference devices

IEC 60904-3, Photovoltaic devices – Part 3: Measurement principles for terrestrial
photovoltaic (PV) solar devices with reference spectral irradiance data
IEC 60904-7, Photovoltaic devices – Part 7: Computation of the spectral mismatch correction
for measurements of photovoltaic devices
IEC 60904-8, Photovoltaic devices – Part 8: Measurement of spectral responsivity of a
photovoltaic (PV) device
IEC 60904-9, Photovoltaic devices – Part 9: Solar simulator performance requirements
IEC 60904-10, Photovoltaic devices – Part 10: Methods of linearity measurement
IEC 61215-1, Terrestrial photovoltaic (PV) modules – Design qualification and type approval –
Part 1: Test requirements
IEC TS 61836, Solar photovoltaic energy systems – Terms, definitions and symbols
IEC 61853-2, Photovoltaic (PV) module performance testing and energy rating – Part 2:
Spectral response, incidence angle, and module operating temperature measurements
IEC 62790, Junction boxes for photovoltaic modules – Safety requirements and tests
ISO 868, Plastics and ebonite – Determination of indentation hardness by means of a
durometer (Shore hardness)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050 and IEC
TS 61836 apply, as well as the following.
3.1
accuracy
quality which characterizes the ability of a measuring instrument to provide an indicated value
close to a true value of the measurand [≈ VIM 5.18]
Note 1 to entry: This term is used in the "true value" approach.
Note 2 to entry: Accuracy is all the better when the indicated value is closer to the corresponding true value.
[SOURCE: IEC 60050-311:2001, 311-06-08]
3.2
control device
irradiance sensor (such as a reference cell or module) that is used to detect drifts and other
problems of the solar sun simulator
3.3
electrically stable power output level
state of the PV module where it will operate under long-term natural sunlight exposure in
general open-air climates, as defined in IEC 60721-2-1
_________________
To be published.
– 10 – IEC 61215-2:2016 © IEC 2016
3.4
repeatability
closeness of agreement between the results of successive measurements of the same
measurand, carried out under the same conditions of measurement, i.e.:
– by the same measurement procedure,
– by the same observer,
– with the same measuring instruments,
– used under the same conditions,
– in the same laboratory,
at relatively short intervals of time [≈ VIM 3.6].
Note 1 to entry: The concept of "measurement procedure" is defined in VIM 2.5.
[SOURCE: IEC 60050-311:2001, 311-06-06]
3.5
reproducibility
closeness of agreement between the results of measurements of the same value of a
quantity, when the individual measurements are made under different conditions of
measurement:
– principle of measurement,
– method of measurement,
– observer,
– measuring instruments,
– reference standards,
– laboratory,
– under conditions of use of the instruments, different from those customarily used,
after intervals of time relatively long compared with the duration of a single measurement [≈
VIM 3.7].
Note 1 to entry: The concepts of "principle of measurement" and "method of measurement" are respectively
defined in VIM 2.3 and 2.4.
Note 2 to entry: The term "reproducibility" also applies to the instance where only certain of the above conditions
are taken into account, provided that these are stated.
[SOURCE: IEC 60050-311:2001, 311-06-07]
4 Test procedures
4.1 Visual inspection (MQT 01)
4.1.1 Purpose
To detect any visual defects in the module.
4.1.2 Procedure
Carefully inspect each module under an illumination of not less than 1 000 lux for conditions
and observations as defined in IEC 61215-1.

Make note of and/or photograph the nature and position of any cracks, bubbles or
delaminations, etc., which may worsen and adversely affect the module performance in sub-
sequent tests.
4.1.3 Requirements
No evidence of major visual defects permitted, as defined in IEC 61215-1.
4.2 Maximum power determination (MQT 02)
4.2.1 Purpose
To determine the maximum power of the module after stabilization as well as before and after
the various environmental stress tests. For determining the power loss from the stress tests,
reproducibility of the test is a very important factor.
4.2.2 Apparatus
a) A radiant source (natural sunlight or a solar simulator class BBA or better in accordance
with IEC 60904-9).
b) A PV reference device in accordance with IEC 60904-2. If a class BBA simulator or better
is used, the reference device shall be a reference module of the same size with the same
cell technology to match spectral responsivity. If such a matched reference device is not
available one of the following two options need to be followed:
1) a Class AAA simulator shall be utilized, or
2) the spectral responsivity of the module according to IEC 60904-8 and the spectral
distribution of the solar simulator need to be measured and the module data corrected
according to IEC 60904-7.
c) A suitable mount for supporting the test specimen and the reference device in a plane
normal to the radiant beam.
d) Apparatus for measuring an I-V curve in accordance with IEC 60904-1.
4.2.3 Procedure
Determine the current-voltage characteristic of the module in accordance with IEC 60904-1 at
a specific set of irradiance and temperature conditions (a recommended range is a cell
2 2
and 1 100 W/m )
temperature between 25 °C and 50 °C and an irradiance between 700 W/m
using natural sunlight or a class BBA or better simulator conforming to the requirements of
IEC 60904-9. In special circumstances when modules are designed for operation under a
different range of conditions, the current-voltage characteristics can be measured using
temperature and irradiance levels similar to the expected operating conditions. For linear
modules (as defined in IEC 60904-10) temperature and irradiance corrections can be made in
accordance with IEC 60891 in order to compare sets of measurements made on the same
module before and after environmental tests. For nonlinear modules (as defined in
IEC 60904-10) the measurement shall be performed within ± 5 % of the specified irradiance
and within ± 2 °C of the specified temperature. However, every effort should be made to
ensure that peak power measurements are made under similar operating conditions, that is
minimize the magnitude of the correction by making all peak power measurements on a
particular module at approximately the same temperature and irradiance.
4.3 Insulation test (MQT 03)
4.3.1 Purpose
To determine whether or not the module is sufficiently well insulated between live parts and
accessible parts.
– 12 – IEC 61215-2:2016 © IEC 2016
4.3.2 Apparatus
a) d.c. voltage source, with current limitation, capable of applying 500 V or 1 000 V plus
twice the maximum system voltage of the module (IEC 61215-1).
b) An instrument to measure the insulation resistance.
4.3.3 Test conditions
The test shall be made on modules at ambient temperature of the surrounding atmosphere
(see IEC 60068-1) and in a relative humidity not exceeding 75 %.
4.3.4 Procedure
a) Connect the shorted output terminals of the module to the positive terminal of a d.c.
insulation tester with a current limitation.
b) Connect the exposed metal parts of the modules to the negative terminal of the tester. If
the modules has no frame or if the frame is a poor electrical conductor, wrap a conductive
foil around the edges. Cover all polymeric surfaces (front- / backsheet, junction box) of the
module with conductive foil. Connect all foil covered parts also to the negative terminal of
the tester.
Some module technologies may be sensitive to static polarization if the module is
maintained at positive voltage to the frame. In this case, the connection of the tester shall
be done in the opposite way. If applicable, information with respect to sensitivity to static
polarization shall be provided by manufacturer.
c) Increase the voltage applied by the tester at a rate not exceeding 500 V/s to a maximum
equal to 1 000 V plus twice the maximum system voltage (IEC 61215-1). If the maximum
system voltage does not exceed 50 V, the applied voltage shall be 500 V. Maintain the
voltage at this level for 1 min.
d) Reduce the applied voltage to zero and short-circuit the terminals of the test equipment
to discharge the voltage build-up in the module.
e) Remove the short circuit.
f) Increase the voltage applied by the test equipment at a rate not exceeding 500 V/s to
500 V or the maximum system voltage for the module, whichever is greater. Maintain the
voltage at this level for 2 min. Then determine the insulation resistance.
g) Reduce the applied voltage to zero and short-circuit the terminals of the test equipment
to discharge the voltage build-up in the module.
h) Remove the short circuit and disconnect the test equipment from the module.
4.3.5 Test requirements
a) No dielectric breakdown or surface tracking during 4.3.4 c).
b) For modules with an area of less than 0,1 m the insulation resistance shall not be less
than 400 MΩ.
c) For modules with an area larger than 0,1 m the measured insulation resistance times the
area of the module shall not be less than 40 MΩ⋅m .
4.4 Measurement of temperature coefficients (MQT 04)
Determine the temperature coefficients of current (α), voltage (β) and peak power (δ) from
module measurements as specified in IEC 60891. The coefficients so determined are valid at
the irradiance at which the measurements were made. See IEC 60904-10 for evaluation of
module temperature coefficients at different irradiance levels.
NOTE For linear modules in accordance to IEC 60904-10, temperature coefficients are valid over an irradiance
range of ± 30 % of this level.

4.5 Measurement of nominal module operating temperature (NMOT) (MQT 05)
4.5.1 General
The power of PV-modules depends on the cell temperature. The cell temperature is primarily
affected by the ambient temperature, the solar irradiance, and the wind speed.
NMOT is defined as the equilibrium mean solar cell junction temperature within an open-rack
mounted module operating near peak power in the following standard reference environment
(SRE):
– Tilt angle: (37 ± 5)°
– Total irradiance: 800 W/m
– Ambient temperature: 20 °C
– Wind speed: 1 m/s
– Electrical load: A resistive load sized such that the module will operate near
its maximum power point at STC or an electronic maximum
power point tracker (MPPT).
NOTE NMOT is similar to the former NOCT except that it is measured with the module under maximum power
rather than in open circuit. Under maximum power conditions (electric) energy is withdrawn from the module,
therefore less thermal energy is dissipated throughout the module than under open-circuit conditions. Therefore
NMOT is typically a few degrees lower than the former NOCT.
NMOT can be used by the system designer as a guide to the temperature at which a module
will operate in the field, and it is therefore a useful parameter when comparing the
performance of different module designs. However, the actual operating temperature at any
particular time is affected by the mounting structure, distance from ground, irradiance, wind
speed, ambient temperature, sky temperature and reflections and emissions from the ground
and nearby objects. For accurate performance predictions, these factors shall be taken into
account.
In the case of modules not designed for open-rack mounting, the method may be used to
determine the equilibrium mean solar cell junction temperature in the SRE, with the module
mounted as recommended by the manufacturer.
4.5.2 Principle
This method is based on gathering actual measured module temperature data under a range
of environmental conditions including the SRE. The data are presented in a way that allows
accurate and repeatable interpolation of the NMOT.
The temperature of the solar cell junction (T ) is primarily a function of the ambient
J
temperature (T ), the average wind speed (v) and the total solar irradiance (G) incident on
amb
the active surface of the module. The temperature difference (T – T ) is largely
J amb
independent of the ambient temperature and is essentially linearly proportional to the
irradiance at levels above 400 W/m .
The module temperature is modelled by: T – T = G / (u – u v)
J amb 0 1
The coefficient u describes the influence of the irradiance and u the wind impact.
0 1
The NMOT value for T is then determined from the model formula above by using T =
J amb
20 °C, irradiance G of 800 W/m and a wind speed v of 1 m/s.
4.5.3 Test procedure
The data for calculating NMOT shall be acquired using the test method (Methodology for
determining module operating temperature) in IEC 61853-2.

– 14 – IEC 61215-2:2016 © IEC 2016
NOTE This test can be performed simultaneously with the outdoor exposure test in 4.8.
4.6 Performance at STC and NMOT (MQT 06)
4.6.1 Purpose
To determine how the electrical performance of the module varies with load at STC
(1 000 W/m , 25 °C cell temperature, with the IEC 60904-3 reference solar spectral irradiance
distribution) and at NMOT (an irradiance of 800 W/m and an ambient temperature of 20 °C
with the IEC 60904-3 reference solar spectral irradiance distribution). The measurement at
STC is used to verify the name plate information of the module.
4.6.2 Apparatus
a) A radiant source (natural sunlight or a solar simulator class BBA or better in accordance
with IEC 60904-9).
b) A PV reference device in accordance with IEC 60904-2. If a class BBA simulator or better
is used, the reference device shall be a reference module of the same size with the same
cell technology to match spectral responsivity. If such a matched reference device is not
available one of the following two options need to be followed:
1) a Class AAA simulator shall be utilized, or
2) the spectral responsivity of the module according to IE
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