SIST EN IEC 60904-9:2021

SLOVENSKI STANDARD
SIST EN IEC 60904-9:2021
01-januar-2021
Nadomešča:
SIST EN 60904-9:2008
Fotonapetostne naprave - 9. del: Klasifikacija lastnosti sončnega simulatorja
Photovoltaic devices - Part 9: Classification of solar simulator characteristics
Ta slovenski standard je istoveten z: EN IEC 60904-9:2020
ICS:
27.160 Sončna energija Solar energy engineering
SIST EN IEC 60904-9:2021 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 60904-9:2021


EUROPEAN STANDARD EN IEC 60904-9

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2020
ICS 27.160 Supersedes EN 60904-9:2007 and all of its amendments
and corrigenda (if any)
English Version
Photovoltaic devices - Part 9: Classification of solar simulator
characteristics
(IEC 60904-9:2020)
Dispositifs photovoltaïques - Partie 9: Classification des Photovoltaische Einrichtungen - Teil 9: Klassifizierung der
caractéristiques des simulateurs solaires Eigenschaften von Sonnensimulatoren
(IEC 60904-9:2020) (IEC 60904-9:2020)
This European Standard was approved by CENELEC on 2020-10-23. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.


European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN IEC 60904-9:2020 E

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SIST EN IEC 60904-9:2021
EN IEC 60904-9:2020 (E)
European foreword
The text of document 82/1756/FDIS, future edition 3 of IEC 60904-9, prepared by IEC/TC 82 "Solar
photovoltaic energy systems" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 60904-9:2020.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2021-07-23
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2023-10-23
document have to be withdrawn
This document supersedes EN 60904-9:2007 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 60904-9:2020 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60891 NOTE Harmonized as EN 60891
IEC 60904-2 NOTE Harmonized as EN 60904-2
IEC 60904-7:2019 NOTE Harmonized as EN IEC 60904-7:2019 (not modified)


2

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SIST EN IEC 60904-9:2021
EN IEC 60904-9:2020 (E)
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60904-1 - Photovoltaic devices - Part 1: EN IEC 60904-1 -
Measurement of photovoltaic current-
voltage characteristics
IEC 60904-3 - Photovoltaic devices - Part 3: EN IEC 60904-3 -
Measurement principles for terrestrial
photovoltaic (PV) solar devices with
reference spectral irradiance data
1
IEC/TR 60904-14 — Photovoltaic devices - Part 14: - -
Guidelines for production line
measurements of single junction PV
module maximum power output and
reporting at standard test conditions
IEC/TS 61836 - Solar photovoltaic energy systems - - -
Terms, definitions and symbols


1
To be published. Stage at the time of publication: 82/1748/DTR.
3

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IEC 60904-9

®


Edition 3.0 2020-09




INTERNATIONAL



STANDARD




NORME


INTERNATIONALE
colour

inside










Photovoltaic devices –

Part 9: Classification of solar simulator characteristics



Dispositifs photovoltaïques –

Partie 9: Classification des caractéristiques des simulateurs solaires
















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 27.160 ISBN 978-2-8322-8765-1




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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 7
4 Classification of solar simulator characteristics . 12
5 Measurement procedures . 13
5.1 Introductory remarks . 13
5.2 Spectral match . 13
5.2.1 General . 13
5.2.2 Apparatus . 13
5.2.3 Procedure . 14
5.2.4 Measurement uncertainty. 15
5.3 Non-uniformity of irradiance in the test plane . 16
5.3.1 General . 16
5.3.2 Apparatus . 16
5.3.3 Procedure . 17
5.3.4 Uncertainty of non-uniformity measurement . 19
5.4 Temporal instability of irradiance . 19
5.4.1 Solar simulators for I-V measurement . 19
5.4.2 Solar simulators for irradiance exposure . 21
5.4.3 Classification for temporal instability . 21
5.4.4 Uncertainty of temporal instability . 22
5.5 AM1.5 spectral coverage (SPC) . 22
5.6 AM1.5 spectral deviation (SPD) . 22
6 Name plate and data sheet . 22
Annex A (informative) Assessment of spectral mismatch error: Sensitivity to spectral
irradiance . 24
A.1 General . 24
A.2 Estimation of spectral mismatch-related uncertainty when the spectral
responsivities are known . 24
A.3 Sensitivity of spectral irradiance for spectral mismatch error when the
variation of spectral responsivities is not known . 25
A.4 Reporting . 28
Bibliography . 29

Figure 1 – Locations for spectral irradiance measurement of a rectangular test area
(left) and a circular test area (right) . 15
Figure 2 – Evaluation of STI for a long pulse solar simulator . 20
Figure 3 – Evaluation of STI for a short pulse solar simulator. 21
Figure A.1 – Virtual spectral responsivity with its dispersions and the modelling
parameters . 25
Figure A.2 – Reference SR curves for typical PV technologies . 27
Figure A.3 – Robustness of spectral irradiance regarding spectral mismatch error . 28

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Table 1 – Global reference solar spectral irradiance distribution given in IEC 60904-3
contribution of wavelength intervals to total irradiance in the restricted wavelength
range 400 nm to 1 100 nm . 9
Table 2 – Global reference solar spectral irradiance distribution given in IEC 60904-3
contribution of wavelength intervals to total irradiance in the extended wavelength
range 300 nm to 1 200 nm . 10
Table 3 – Definition of solar simulator classifications . 12
Table A.1 – Reference SR curves for typical PV technologies . 26

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

PHOTOVOLTAIC DEVICES –

Part 9: Classification of solar simulator characteristics

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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 60904-9 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
This third edition cancels and replaces the second edition issued in 2007. It constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• Changed title;
• Added spectral match classification in an extended wavelength range;
• Introduction of new A+ class;
• Definition of additional parameters for spectral irradiance evaluation;
• Added apparatus sections for spectral irradiance measurement and spatial uniformity
measurement;

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IEC 60904-9:2020 © IEC 2020 – 5 –
• Revised procedure for spectral match classification (minimum 4 measurement locations);
• Revised measurement procedure for spatial uniformity of irradiance;
• Added informative Annex A for sensitivity analysis of spectral mismatch error related to
solar simulator spectral irradiance.
The text of this standard is based on the following documents:
FDIS Report on voting
82/1756/FDIS 82/1775/RVD

Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60904 series, published under the general title Photovoltaic
devices, can be found on the IEC web site.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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.

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PHOTOVOLTAIC DEVICES –

Part 9: Classification of solar simulator characteristics



1 Scope
IEC standards for photovoltaic devices require the use of specific classes of solar simulators
deemed appropriate for specific tests. Solar simulators can be either used for performance
measurements of PV devices or endurance irradiation tests. This part of IEC 60904 provides
the definitions of and means for determining simulator classifications at the required
irradiance levels used for electrical stabilization and characterisation of PV devices.
This document is applicable for solar simulators used in PV test and calibration laboratories
and in manufacturing lines of solar cells and PV modules. The A+ category is primarily
intended for calibration laboratories and is not considered necessary for power measurements
in PV manufacturing and in qualification testing. Class A+ has been introduced because it
allows for reduction in the uncertainty of secondary reference device calibration, which is
usually performed in a calibration laboratory. Measurement uncertainty in PV production lines
will directly benefit from a lower uncertainty of calibration, because production line
measurements are performed using secondary reference devices.
In the case of PV performance measurements, using a solar simulator of a particular class
does not eliminate the need to quantify the influence of the simulator on the measurement by
making spectral mismatch corrections and analysing the influences of spatial non-uniformity
of irradiance in the test plane and temporal stability of irradiance on that measurement. Test
reports for PV devices tested with the simulator report the class of simulator used for the
measurement and the method used to quantify the simulator’s effect on the results.
The purpose of this document is to define classifications of solar simulators for use in indoor
measurements of terrestrial photovoltaic devices. Solar simulators are classified as A+, A, B
or C based on criteria of spectral distribution match, irradiance non-uniformity in the test
plane and temporal instability of irradiance. This document provides the required
methodologies for determining the classification of solar simulators in each of the categories.
A solar simulator which does not meet the minimum requirements of class C cannot be
classified according to this document.
For spectral match classification a new procedure has been added. This procedure addresses
the actual need for an extended wavelength range, which is arising from advances in solar
cell technology (such as increased spectral responsivity below 400 nm) as well as solar
simulator technology (use of component LEDs). The procedure of the second edition of this
standard is still valid, but is only applied if backward compatibility of classification for solar
simulators already in use and for solar simulators in production/sale is required. This
document is referred to by other IEC standards, in which class requirements are laid down for
the use of solar simulators. The solar simulator characteristics described in this document
are not used in isolation to imply any level of measurement confidence or measurement
uncertainty for a solar simulator application (for example, PV module power measurement).
Measurement uncertainties in each application depend on many factors, several of which are
outside the scope of this document:
• Characteristics of the solar simulator, possibly including characteristics not covered by this
document;
• Methods used to calibrate and operate the solar simulator;
• Characteristics of the device(s) under test (for example, size and spectral responsivity);
• Quantities measured from the device(s) under test, including equipment and methods
used for measurement;

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• Possible corrections applied to measured quantities.
When applications require a certain solar simulator characteristic, it is preferable to specify a
numerical value rather than a letter classification (for example, “≤ 5 % non-uniformity of
irradiance” rather than “Class B non-uniformity of irradiance”). If not obvious from the
application, it should also be indicated how the required simulator characteristic correlates to
relevant measured quantities. Since PV module power measurement is one of the most
common applications for solar simulators, brief guidance on this application is given in
informative notes for each solar simulator characteristic described in this document. This
document is used in combination with IEC TR 60904-14, which deals with best practice
recommendations for production line measurements of single-junction PV module maximum
power output and reporting at standard test conditions. For output power characterization of
PV devices, IEC TR 60904-14 addresses the relevance of the letter grades (A+, A, B, C) for
measurement uncertainty.
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 60904-1, Photovoltaic devices – Part 1: Measurement of photovoltaic current-voltage
characteristics
IEC 60904-3, Photovoltaic devices – Part 3: Measurement principles for terrestrial
photovoltaic (PV) solar devices with reference spectral irradiance data
1
IEC TR 60904-14:– , Photovoltaic devices – Part 14: Guidelines for production line
measurements of single junction PV module maximum power output and reporting at standard
test conditions
IEC TS 61836, Solar photovoltaic energy systems – Terms, definitions and symbols
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC TS 61836 together
with 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
solar simulator
equipment employing a light source with a spectral distribution similar to the natural sunlight
used to evaluate characteristics of PV devices
Note 1 to entry: Simulators usually consist of three main components:
a) light source(s) and associated power supply;
b) any optics and filters required to modify the output beam to meet the classification requirements; and
___________
1
 Under preparation. Stage at the time of publication: 82/1748/DTR.

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c) the necessary controls to operate the simulator. If the system is used for maximum power determination of PV
modules, the I-V data acquisition system shall be additionally regarded as integral part. Solar simulators shall
be labelled by their mode of operation during a test cycle. These are steady state, single pulse, and multi-
pulse.
Note 2 to entry: Various types of solar simulators are commonly used to determine the current-voltage (I-V)
characteristics of PV devices as defined in IEC 60904-1. Generally, these work as single lamp systems where the
PV device is placed in the designated test area or multiple lamp systems, which are based on the superposition of
light cones. Examples include:
a) Pulsed single lamp or multilamp solar simulator operated in a dark room with typically several metres distance
between light source(s) and PV device. Internal reflections from walls may be suppressed by use of baffles.
b) Pulsed solar simulator operated in a casing or in tabletop configuration with typically less than 1 m distance
between light source(s) and PV device. Diffuser plates and reflectors may be used to achieve the specified
spatial uniformity of irradiance.
c) Steady state single lamp or multilamp solar simulator operated in a dark room with typically several metres
distance between light source(s) and PV device. Internal reflections from walls may be suppressed by use of
baffles.
d) LED based multilamp solar simulator operated with typically less than 1 m distance between light source(s)
and PV device.
Note 3 to entry: Pulsed solar simulators can be further subdivided into long pulse systems acquiring the total I-V
characteristic or a section of the I-V characteristic during one flash and systems acquiring one I-V data point per
flash. Several lamp types may be used in a multilamp solar simulator. These instruments are spectrally tuneable
instruments, which work with superposition of different spectral irradiances, emitted from various lamp types. If
available, in addition to the rating, the reported test data should be referred to for evaluation of the applicability of
the solar simulator for a specific use or testing purposes.
Note 4 to entry: Multilamp systems can be further subdivided into systems, where each lamp irradiates the total
test area, and systems, where a single lamp just irradiates a part of the test area.
Besides the light source, the lamp power supply and the optics, also the I-V data acquisition, the electronic load
and the operating software may be an integral part of the solar simulator. Requirements for the related
measurement technique are included in other parts of the IEC 60904 series.
3.2
test plane
plane intended to contain the device under test
3.3
designated test area
region of the test plane that is assessed for solar simulator classification
Note 1 to entry: If required, typical geometries can be specified. A specification related to a circular geometry is
also permitted.
3.4
data sampling time
time to take a single data set (irradiance, voltage, current). In the case of simultaneous
measurement, this is given by the characteristic of the A/D converter. In the case of
multiplexed systems the data sampling rate is the multiplexing rate.
Note 1 to entry: In the case of simultaneous measurement, the data sampling time is given by the characteristic of
the A/D converter. In the case of multiplexed systems the data sampling time is the multiplexing rate.
The data sampling time is used for evaluation of temporal stability.
EXAMPLE In the case of non-simultaneous measurement, a multiplexing time of 1 µs would give a sampling rate
of 1 Mega samples per second; the data sampling time would be 3 µs.
3.5
data acquisition time
time to take the entire or a part of the I-V curve of a PV device
Note 1 to entry: The data acquisition time depends on the number of I-V data points and a delay time that might
be adjustable.
Note 2 to entry: In the case of pulsed solar simulators the data acquisition time is related to the measurements
recorded during a single flash.

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3.6
time for acquiring the I-V characteristic
time for acquiring the entire I-V characteristic of a PV device
Note 1 to entry: If the I-V characteristic of the PV device is measured in a single flash it is equal to the data
acquisition time.
Note 2 to entry: If the I-V characteristic of the PV device is measured through sectoring in different parts with
multiple flashes, it is t
...