IEC 60904-5:2011

IEC 60904-5 ®
Edition 2.1 2022-11
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Photovoltaic devices –
Part 5: Determination of the equivalent cell temperature (ECT) of photovoltaic
(PV) devices by the open-circuit voltage method

Dispositifs photovoltaïques –
Partie 5: Détermination de la température de cellule équivalente (ECT) des
dispositifs photovoltaïques (PV) par la méthode de la tension en circuit ouvert

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IEC 60904-5 ®
Edition 2.1 2022-11
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Photovoltaic devices –
Part 5: Determination of the equivalent cell temperature (ECT) of photovoltaic
(PV) devices by the open-circuit voltage method
Dispositifs photovoltaïques –
Partie 5: Détermination de la température de cellule équivalente (ECT) des
dispositifs photovoltaïques (PV) par la méthode de la tension en circuit ouvert
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-6144-6

IEC 60904-5 ®
Edition 2.1 2022-11
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Photovoltaic devices –
Part 5: Determination of the equivalent cell temperature (ECT) of photovoltaic
(PV) devices by the open-circuit voltage method

Dispositifs photovoltaïques –
Partie 5: Détermination de la température de cellule équivalente (ECT) des
dispositifs photovoltaïques (PV) par la méthode de la tension en circuit ouvert

– 2 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope and object . 6
2 Normative references . 6
3 Measurement principle and requirements . 7
3.1 Principle . 7
3.2 General measurement requirements . 7
4 Apparatus . 8
5 Determination of required input parameters . 8
6 Procedure . 8
6.1 General . 8
6.2 Operating in a controlled environment . 9
6.3 Taking measurements under arbitrary irradiance conditions . 9
7 Calculation of equivalent cell temperature . 9
8 Test report. 12
Bibliography . 13

 IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOVOLTAIC DEVICES –
Part 5: Determination of the equivalent cell temperature (ECT)
of photovoltaic (PV) devices by the open-circuit voltage method

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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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 60904-5 edition 2.1 contains the second edition (2011-02) [documents 82/595/CDV
and 82/626/RVC] and its amendment 1 (2022-11) [documents 82/2069/FDIS and
82/2082/RVD].
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions are in green text, deletions are in strikethrough
red text. A separate Final version with all changes accepted is available in this
publication.
– 4 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
International Standard IEC 60904-5 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
This second edition constitutes a technical revision.
The main technical changes with regard to the previous edition are as follows:
• added and updated normative references;
• added reporting section;
• added method on how to extract the input parameters;
• rewritten method on how to calculate ECT;
• reworked formulae to be in line with IEC 60891.
A list of all parts of IEC 60904 series, under the general title Photovoltaic devices, 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 the base publication and its amendment will
remain unchanged until the stability date indicated on the IEC web site under 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.
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.
 IEC 2022
INTRODUCTION
When temperature sensors, such as thermocouples, are used to determine the cell
temperature of PV devices under natural or simulated steady-state irradiance, two main
problems arise. First, a considerable spread of temperature can be observed over the area of
the module. Second, as the solar cells are usually not accessible, sensors are attached to the
back of the module and the measured temperature thus is influenced by the thermal
conductivity of the encapsulant and back materials. These problems are aggravated when
determining the equivalent cell temperature for on-site measurements of array performance
where all cells have slightly different temperatures and one cannot easily determine the
average cell temperature.
The equivalent cell temperature (ECT) is the average temperature at the electronic junctions
of the device (cells, modules, arrays of one type of module) which equates to the current
operating temperature if the entire device were operating uniformly at this junction
temperature.
For modules with large thermal inertia such as glass-glass construction for BIPV applications,
measurements become even more challenging with increased temperature difference between
the cell and module external temperatures during transient conditions. In addition, for bifacial
PV modules the temperature sensors may shade an active cell, potentially even creating local
hotspots where sensors are located on effective cell areas.
NOTE 1 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:
– 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 2 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.

– 6 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
PHOTOVOLTAIC DEVICES –
Part 5: Determination of the equivalent cell temperature (ECT)
of photovoltaic (PV) devices
by the open-circuit voltage method

1 Scope and object
This part of IEC 60904 describes the preferred method for determining the equivalent cell
temperature (ECT) of PV devices (cells, modules and arrays of one type of module), for the
purposes of comparing their thermal characteristics, determining NOCT (nominal operating
cell temperature) or alternatively NMOT (nominal module operating temperature), and
translating measured I-V characteristics to other temperatures.
This standard applies to linear devices with logarithmic V dependence on irradiance and in
OC
stable conditions. It may be used for all technologies but one has to verify that there is no
preconditioning effect influencing the measurement.
2 Normative references
The following referenced documents are indispensable for the application 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 60891, Photovoltaic devices – Procedures for temperature and irradiance corrections
to measured I-V characteristics
IEC 60904-1, Photovoltaic devices – Part 1: Measurement of photovoltaic current-voltage
characteristics
IEC TS 60904-1-2:2019, Photovoltaic devices – Part 1-2: Measurement of current-voltage
characteristics of bifacial photovoltaic (PV) devices
IEC 60904-2, Photovoltaic devices – Part 2: Requirements for reference solar 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 60904-10, Photovoltaic devices – Part 10: Methods of linearity measurement
IEC 61215, Crystalline silicon terrestrial photovoltaic (PV) modules – Design qualification
and type approval
IEC 61829, Crystalline silicon photovoltaic (PV) array – On-site measurement of I-V
characteristics
ISO/IEC 17025, General requirements for competence of testing and calibration laboratories

 IEC 2022
3 Measurement principle and requirements
3.1 Principle
The method described below is based on the fact that the open-circuit voltage (V ) of a solar
OC
cell changes with temperature in a predictable fashion. If the open-circuit voltage of the
device at standard test conditions is known, together with its temperature coefficient, the
equivalent temperature of all the cells in the device can be determined. The open-circuit
voltage is also slightly affected by the irradiance, so an additional correction may be required
as outlined in IEC 60891. Experience shows that the equivalent cell temperature can be
determined more precisely by the method described herein than by any alternative technique
[1] . However, as the temperature coefficient β drops rapidly increased variability and errors
have been observed at irradiances below 200 400 W/m , so this method should only be used
at irradiances above this threshold.
3.2 General measurement requirements
a) Use of the ECT method requires calibration of the device to be measured.
NOTE It is not sufficient to use calibration of another device of the same type, because even small
differences in parameters between a calibrated device and a similar one can lead to significant errors (e.g.
0,3 % variation in module V leads to 1 °C impact on ECT temperature).
OC
ab) The device under test needs to match the following criteria:
1) The variation of V needs to be linear as defined in IEC 60904-10 with respect to
OC
temperature.
2) The variation of V with respect to irradiance needs to follow a logarithmic
OC
dependence with irradiance have a quadratic dependence on the logarithm of
irradiance.
3) It needs to have an ohmic series resistance as otherwise there will be different ECT-
coefficients for different temperature regions.
4) The shunt resistances of the device need to be reasonably high, as for the majority of
commercially available devices, as otherwise there will be different ECT-coefficients
for different temperature regions.
bc) The irradiance measurements shall be made using a PV reference device packaged and
calibrated in conformance with IEC 60904-2 or a pyranometer. The PV reference device
shall either be spectrally matched to the test specimen, or a spectral mismatch correction
shall be performed Either use a PV reference device that is spectrally matched to the
device under test (DUT), or perform a spectral mismatch correction and report in
conformance with IEC 60904-7. The reference device shall be linear in short-circuit
current as defined in IEC 60904-10 over the irradiance range of interest.
In accordance with IEC 60904-2, to be considered spectrally matched, a reference device
shall be constructed using the same cell technology and encapsulation package as the
test device under test. Otherwise the spectral mismatch will have to be reported.
NOTE Some devices might have a significant spectral dependency in the open-circuit voltage. In such a case,
a spectroradiometer would be needed to ensure stable incident spectrum.
d) Some devices, in particular multi-junction, might have a spectral dependency of the open-
circuit voltage [2]. For these devices, the spectral irradiance shall be determined with a
spectroradiometer.
ce) The active surface of the specimen device under test shall be coplanar within ±2° of the
active surface of the reference device.
df) Voltages shall be measured to an accuracy of ± 0,2 % of the open-circuit voltage using
independent leads from the terminals of the specimen and keeping them as short as
possible. The measurement ranges of the data acquisition should be carefully chosen. If
the test specimen is a module, the 4-wire connection should start at the terminals or
connectors. If the test specimen is a cell, the 4-wire connection should start at the bus
—————————
Numbers in square brackets refer to the Bibliography.

– 8 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
bars. For appropriate connection method and measurement of voltages refer to
IEC 60904-1.
4 Apparatus
In addition to the general measurement requirements of Clause 3 the following equipment is
required to perform I-V characteristic measurements:
a) A PV reference device that meets the conditions stated in 3 ac).
b) Equipment to measure the open-circuit voltage to an precision instrumental measurement
uncertainty better than ±0,2 %.
c) Equipment to measure temperature to an precision instrumental measurement uncertainty
of ±1 K.
5 Determination of required input parameters
The procedure requires a number of input parameters. These are:
• Temperature coefficient of the open circuit voltage, β. This shall be determined from cell
or module measurements of representative samples in accordance with IEC 60891.
• Open-circuit voltage (V ) at a reference condition (G , T ) in accordance with
OC1 1 1
IEC 60904-1 for a cell or module or in accordance with IEC 61829 for a PV array. The
reference condition is often chosen to be the standard test conditions as defined in
IEC 61215, i.e. G = 1 000 W/m and T = 25 °C.
STC STC
• The procedure requires a constant, , which is also interpreted as the thermal diode
a
voltage. The determination of this requires the measurement of the open-circuit voltage at
two different irradiance levels G and G , one of which may be the point G ,T .
3 4 1 1
• Relative temperature coefficient of open circuit voltage, β . This shall be determined from
rel
cell or module measurements of representative samples in accordance with IEC 60891.
For bifacial modules, the temperature coefficient only needs to be determined from front
side measurements.
• Open-circuit voltage (V ) at a reference condition (G , T ) in accordance with
OC1 1 1
IEC 60904-1 or IEC TS 60904-1-2 for a cell or module or in accordance with IEC 61829 for
a PV array. The reference condition is often chosen to be the standard test conditions, i.e.
G = 1 000 W/m and T = 25 °C with a reference spectral irradiance distribution as
STC STC
defined in IEC 60904-3.
, T ) is carried out, it is recommended to apply insulating
• When outdoor measurement (G
1 1
thermal tape, e.g. polyethylene foam, 1 mm thickness, with mass density less than
0,03 g/cm , to cover the temperature sensor which is fixed by either aluminium or
polyimide tape. If the temperature around the module is subjected to spatial and temporal
variability, use of insulating thermal tape shields the temperature sensor from influence of
environmental factors such as wind, allowing more accurate measurements.
NOTE A method to determine the mass density can be found in ISO 7214[4].
• The procedure requires the irradiance correction factors, B and B . B is linked to the
1 2 1
thermal diode voltage and B accounts for non-linearity of V with irradiance scaling. The
2 OC
determination of these constants requires the measurement of the module I-V
characteristic in accordance with IEC 60891 under at least five different irradiance levels.
6 Procedure
6.1 General
The procedure can be carried out either in a controlled environment or by taking
measurements at arbitrary irradiances and correcting to the reference irradiance G .
 IEC 2022
6.2 Operating in a controlled environment
o
a) Mount the radiation sensor coplanar with the test device to an agreement better than ±2 .
b) Set the irradiance to be equal to that of the reference condition G using the reference
device.
c) For bifacial modules, a non-irradiated background is required as described in
IEC TS 60904‑1‑2.
c)d) Take simultaneous readings of the open-circuit voltage of the test device under test
V and the incident irradiance (G ). Should there be any variation in the irradiance,
OC2 2
treat as a measurement in arbitrary irradiance conditions as given in 6.3 and carry out the
appropriate correction. An irradiance correction should be carried out if the scatter in the
determined ECT is more than 1 K.
d)e) Calculate the ECT as described in Clause 7.
6.3 Taking measurements under arbitrary irradiance conditions
a) Mount the radiation sensor coplanar with the test device under test to an agreement better
than ±2 °.
b) For bifacial modules, two different setups are recommended for the measurement:
Method 1: use a low reflectivity black cover material to reduce back-to-front irradiance
ratio to < 1 %, in order to minimize the rear irradiance contribution. The cover should be
mounted behind the module in a way to limit interference with the module natural
convective heat dissipation as much as possible.
Method 2: measure the plane-of-array irradiance on front side G and the average
f
i
irradiance on the rear side G using PV reference devices compliant to IEC 60904-2. G
r r
i i
is the average of at least 5 measurement points located per the requirements of
IEC TS 60904‑1‑2:2019, 6.3.2. The equivalent irradiance GE on the bifacial module is
then determined by:
GG+×φG
Ef r (1)
i i i
where φ is the module bifaciality coefficient as determined in accordance with
IEC TS 60904-1-2.
NOTE 1 Decision on which method to use is left to the user, on consideration of the targeted measurement
uncertainty budget. Method 1 is expected to enable lower uncertainty when applied to NOCT or NMOT
measurements, and for translating field measured I-V characteristics to standard test conditions.
NOTE 2 When applying method 2, particularly for bifacial systems, proper selection of the modules to be
tested has to consider thermal and irradiance non-uniformities at the system level. IEC 61829 provides some
guidance on the selection of typical modules within a PV array, recommending in particular to avoid selecting
modules at ends of rows.
b)c) Take simultaneous readings of the open-circuit voltage of the test device under test
V and the incident plane-of-array irradiance G (method 1), or alternatively of the
OC2 2
irradiance on front side G and average irradiance on the rear side G (method 2).
f r
2 2
c)d) Carry out a correction of V to an irradiance equal to G .
OC2 1
d)e) Calculate the ECT as described in Clause 7.
7 Calculation of equivalent cell temperature
The equivalent cell temperature ECT is derived from the single diode equations describing the
current voltage characteristic.
Solving the equation for V = V , with V = V and I = I = 0 results in the following
2 OC2 1 OC1 2 1
dependence of the open circuit voltage:
=
– 10 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
 G 
V = V +V β(T − T)+ aln
OC2 OC1 OC1 2 1 
(1)
G
 1
where
V is the open-circuit voltage measured in Clause 5 at the irradiance G and module
OC1 1
temperature T ;
V is the open-circuit voltage measured in Clause 6 at irradiance G and module
OC2 2
temperature T .
the temperature coefficient of the open-circuit voltage β has also been measured as
part of Clause 5 in accordance with IEC 60891;
the parameter, , is the thermal diode voltage, which can be determined from
a
measurements at different light intensities but identical temperatures as:

V − V
OC4 OC3
a =
(2)
V ln (G /G)
OC3 4 3
where V and V are the voltages measured in Clause 5 at the same module
OC3 OC4
temperatures but at different irradiances G and G , respectively.
3 4
Instead of the irradiances G and G , one can also use the ratio of short-circuit currents,
1 2
which then is called self-reference. This requires short circuit current to be linear according to
IEC 60904-10. This simplifies the measurements to be taken significantly as one essentially
eliminates the requirement for measuring the irradiance and the dependence on the spectrally
matched devices.
The relation between the different values of V can then be rewritten to calculate the
OC
equivalent ECT as:
 
 
1 V G
OC2 2
ECT= T = T + −1− a ln 
 
2 1
  (3)
β V G
 OC1 1 
 
 
NOTE This assumes that the spatial and thermal non-uniformity between the two V is identical. For non-uniform
OC
temperature or illumination there will be a small error in ECT because the equivalent circuit model assumes
uniform temperature and illumination.
In the case of base measurements described in Clause 5 being taken at standard test
conditions, the ECT can be determined as:
 
V  G 
OC2 2
ECT= 25°C+ −1− a ln 
 
  (4)
β V 1 000
 OC,STC  
 
This equation is closely related to the formulation of method 1 in the standard for temperature
and irradiance corrections (IEC 60891). The factor a is linked to the number of cells
(junctions) in series in the module (n ) as well as the thermal voltage D as defined in
s
IEC 60891. Thus one can write the ECT in terms of this standard as:
 
 
V G
−1
OC2 2
ECT= T = T +β − 1+ D× n ×ln 
2 1  s 
(5)
 
V G
 OC1  1
 
Solving the equation for V = V , with V = V and I = I = 0 results in the
2 OC2 1 OC1 2 1
 IEC 2022
following dependence of the open circuit voltage:
GG 
f GG, =1+×B ln + B×ln
( )

12 1 2
GG
22
 
V ×+1,β ×(T −T)×f (GG )
oc1 rel 2 1 1 2
 
V =
oc2
f GG,
( )
where
V is the open-circuit voltage measured in Clause 5 at the chosen reference
OC1
conditions, irradiance G and module temperature T ;
1 1
is the open-circuit voltage measured in Clause 6 at irradiance G and
V
OC2 2
module temperature T ;
the relative temperature coefficient of the open-circuit voltage β and the
rel
irradiance correction factors B and B are determined in Clause 5.
1 2
NOTE These formulae are derived from the IEC 60891 correction procedure 2 [3].
For measurement of bifacial modules using method 2, the irradiance G has to be
replaced by the equivalent irradiance G .
E

GG
f GG, =1+×B ln + B×ln 
( )
1 E 1 2

GG
EE
22

V ×+1,β ×(T −T)×f GG
( )
oc1 rel 2 1 1 E
2
V =
oc2
f GG,
( )
1 E
The relation between the different values of V can then be rewritten to calculate
OC
the equivalent ECT per the formulas given below, for monofacial (6) and bifacial (7)
devices:
V
OC2
ECT=T=T+ × × f GG, −1
( )

2 1 12
V
β ×f GG,
( ) OC1
rel 1 2
 
1 V
OC2
ECT=T=T+ × × f GG, −1
( )
21  1 E 
V
β ×f GG,
 OC1 
( )
rel 1 E
In the case of base measurements described in Clause 5 being taken at standard

– 12 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
test conditions, the ECT for monofacial devices can be determined as:

V
OC2
ECT=T=25+ × × f 1000,G−1
( )
V
βf× 1000,G 
( ) OC, STC

rel 2
8 Test report
A test report with measured performance characteristics and test results shall be prepared by
the test agency in accordance with ISO/IEC 17025. The test report shall contain the following
data:
a) A title.
b) Name and address of the test laboratory and location where the tests were carried out.
c) Unique identification of the report and of each page.
d) Name and address of client.
e) A description and identification of the specimen device under test (solar cell, sub-
assembly of solar cells or PV module).
f) Description of the test environment (natural or simulated sunlight and, in the latter case,
brief description and class of simulator).
g) Date of receipt of test item and date(s) of calibration or test, where appropriate.
h) Reference to sampling procedure, where relevant.
i) Identification of calibration or test method used.
j) Any deviations from, additions to or exclusions from the calibration or test method, and
any other information relevant to a specific calibration or test, such as environmental
conditions.
k) Identification of the method for determination of input parameters.
l) A statement of the result and the estimated uncertainty of test results.
m) A signature and title, or equivalent identification of the person(s) accepting responsibility
for the content of the test report, and the date of issue.
n) A statement to the effect that the results relate only to the specimen device tested.
o) A statement that the test report shall not be reproduced except in full, without the written
approval of the laboratory.
 IEC 2022
Bibliography
[1] S. Krauter, A. Preiss, "Comparison of module temperature measurement methods",
Conference record of the IEEE Photovoltaic Specialists Conference,
10.1109/PVSC.2009.5411669
[2] M. Pravettoni, A. Virtuani, K. Keller, M. Apolloni, H. Mullejans, "Spectral Mismatch
Effect to the Open-circuit Voltage in the Indoor Characterization of Multi-junction Thin-
th
film Photovoltaic Modules", 2013 IEEE 39 Photovoltaic Specialists Conference,
10.1109/PVSC.2013.6744249
[3] C. Monokroussos, H. Mullejans, Q. Gao, W. Herrmann, "I-V translation procedure for
th
higher accuracy and compliance with PERC cell technology requirements", 35
European Photovoltaic Solar Energy Conference (EUPVSEC), online, 2020,
10.4229/EUPVSEC20202020-4AV.2.19
[4] ISO 7214: Cellular plastics – Polyethylene – Methods of test

___________
– 14 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
SOMMAIRE
AVANT-PROPOS . 15
INTRODUCTION . 17
1 Domaine d’application et objet . 18
2 Références normatives . 18
3 Principe et exigences de mesure . 19
3.1 Principe . 19
3.2 Exigences générales de mesure . 19
4 Appareillage . 20
5 Détermination des paramètres d’entrée exigés . 20
6 Procédure . 21
6.1 Généralités. 21
6.2 Fonctionnement dans un environnement contrôlé . 21
6.3 Relevé de mesures dans des conditions d’éclairement arbitraires . 21
7 Calcul de la température de cellule équivalente . 22
8 Rapport d’essai . 24
Bibliographie . 26

 IEC 2022
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
DISPOSITIFS PHOTOVOLTAÏQUES –
Partie 5: Détermination de la température de cellule
équivalente (ECT) des dispositifs photovoltaïques (PV)
par la méthode de la tension en circuit ouvert

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisation mondiale de normalisation
composée de l’ensemble des comités électrotechniques nationaux (Comités nationaux de l’IEC). L’IEC a pour
objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines
de l’électricité et de l’électronique. A cet effet, l’IEC – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de l’IEC"). Leur élaboration est confiée à des
comités d’études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec l’IEC, participent
également aux travaux. L’IEC collabore étroitement avec l’Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de l’IEC concernant les questions techniques représentent, dans la mesure
du possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de l’IEC
intéressés sont représentés dans chaque comité d’études.
3) Les Publications de l’IEC se présentent sous la forme de recommandations internationales et sont agréées
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et régionales. Toutes divergences entre toutes Publications de l’IEC et toutes publications nationales ou
régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
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fournissent des services d’évaluation de conformité et, dans certains secteurs, accèdent aux marques de
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indépendants.
6) Tous les utilisateurs doivent s’assurer qu’ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à l’IEC, à ses administrateurs, employés, auxiliaires ou
mandataires, y compris ses experts particuliers et les membres de ses comités d’études et des Comités
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8) L’attention est attirée sur les références normatives citées dans cette publication. L’utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente publication de l’IEC peuvent faire
l’objet de droits de brevet. L’IEC ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits
de brevets.
Cette version consolidée de la Norme IEC officielle et de son amendement a été
préparée pour la commodité de l'utilisateur.
L’IEC 60904-5 édition 2.1 contient la deuxième édition (2011-02) [documents 82/595/CDV
et 82/626/RVC] et son amendement 1 (2022-11) [documents 82/2069/FDIS et
82/2082/RVD].
Dans cette version Redline, une ligne verticale dans la marge indique où le contenu
technique est modifié par l'amendement 1. Les ajouts sont en vert, les suppressions
sont en rouge, barrées. Une version Finale avec toutes les modifications acceptées est
disponible dans cette publication.

– 16 – IEC 60904-5:2011+AMD1:2022 CSV
 IEC 2022
La Norme internationale IEC 60904-5 a été établie par le comité d'études 82 de l’IEC:
Systèmes de conversion photovoltaïque de l'énergie solaire.
Cette deuxième édition constitue une révision technique.
Les principaux changements techniques par rapport à l’édition précédente sont les suivants:
• ajout et mise à jour de références normatives;
• ajout d’une section concernant le rapport;
• ajout d’une méthode explicitant comment extraire les paramètres d’entrée;
• réécriture de la méthode explicitant comment calculer ECT;
• travail sur les formules pour qu’elles soient cohérentes avec l’IEC 60891.
Une liste de toutes les parties de la série IEC 60904, présentées sous le titre général
Dispositifs photovoltaïques, peut être consultée sur le site web de l’IEC.
Cette publication a été rédigée selon les Directives ISO/IEC, Partie 2.
Le comité a décidé que le contenu de la publication de base et de son amendement ne sera
pas modifié avant la date de stabilité indiquée sur le site web de l’IEC sous webstore.iec.ch
dans les données relatives à la publication recherchée. A cette date, la publication sera
• reconduite,
• supprimée,
• remplacée par une édition révisée, ou
• amendée.
IMPORTANT – Le logo "colour inside" qui se trouve su
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