IEC 60704-2-7:2020

Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 2-7: Particular requirements for fans

IEC 60704-2-7:2020 is available as IEC 60704-2-7:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60704-2-7:2020 applies to electrical fans (including their accessories and their component parts) for household and similar use, designed for AC or DC supply. The motor, the impeller and their housing, if any, form a single unit. These particular requirements apply to:
– conventional fans,
– table fans,
– pedestal fans,
– ceiling fans,
– bladeless fans,
– wall bracket fans,
– ceiling bracket fans,
– louver fans,
– tower fans,
– ventilating and partition ventilating fans.
This standard does not apply to:
– fans that are part of a ventilation system,
– fans designed exclusively for industrial purposes,
– fans that are part of an appliance (for example cooling fans),
– fans with additional functions (for example heating, humidifying).
Limitations for the use of this test code are given in the scope of IEC 60704-1.
This second edition cancels and replaces the first edition published in 1997. This edition constitutes a technical revision.
This edition includes the following significant changes with respect to the previous edition:
a) it includes additional fan categories as defined in IEC 60879:2019 and IEC 60665:2018;
b) it includes standard deviations of sound power levels in 1.3;
c) a comparison method has been added;
d) the normative references have been updated (ISO 3744:2010 and ISO 3743-1:2010);
e) it has been adjusted with regard to IEC 60704-1:2010.
This International Standard is to be used in conjunction with IEC 60704 1:2010, Household and similar electrical appliances – Test code for the determination of airborne acoustical noise – Part 1: General requirements. This Part 2-7 supplements or modifies the corresponding clauses in IEC 60704-1:2010, so as to establish the test code for fans.

Appareils électrodomestiques et analogues - Code d'essai pour la détermination du bruit aérien - Partie 2-7: Exigences particulières pour les ventilateurs

IEC 60704-2-7:2020 est disponible sous forme de IEC 60704-2-7:2020 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L'IEC 60704-2-7:2020 s'applique aux ventilateurs électriques (y compris leurs accessoires et composants) qui sont destinés à des usages domestiques et analogues et conçus pour une alimentation en courant alternatif ou en courant continu. Le moteur, les pales et leur boîtier, le cas échéant, constituent un bloc. Ces exigences particulières s'appliquent aux:
– ventilateurs conventionnels;
– ventilateurs de table;
– ventilateurs sur pied;
– ventilateurs de plafond;
– ventilateurs sans pales;
– ventilateurs à applique murale;
– ventilateurs à applique au plafond;
– ventilateurs rotatifs;
– ventilateurs à colonne;
– aérateurs et aérateurs de cloison.
La présente norme ne s'applique pas aux:
– ventilateurs qui font partie intégrante d'un système de ventilation;
– ventilateurs conçus exclusivement pour des usages industriels;
– ventilateurs qui font partie d'un appareil (par exemple les ventilateurs de refroidissement);
– ventilateurs avec des fonctions supplémentaires (par exemple chauffage, humidification).
Les limites d'utilisation de ce code d'essai sont données dans le domaine d'application de l'IEC 60704-1.
Cette deuxième édition annule et remplace la première édition parue en 1997. Cette édition constitue une révision technique.
Cette édition inclut les modifications majeures suivantes par rapport à l'édition précédente:
a) elle inclut des catégories de ventilateurs supplémentaires, définies dans l'IEC 60879:2019 et l'IEC 60665:2018;
b) des écarts-types sont fournis pour les niveaux de puissance acoustique en 1.3;
c) une méthode comparative a été ajoutée;
d) les références normatives ont été mises à jour (ISO 3744:2010 et ISO 3743-1:2010);
e) le présent document a fait l'objet de réajustements par rapport à l'IEC 60704-1:2010.
Cette Norme Internationale doit être utilisée conjointement avec l'IEC 60704-1:2010, Appareils électrodomestiques et analogues – Code d'essai pour la détermination du bruit aérien – Partie 1: Règles générales. La présente Partie 2-7 complète ou modifie les articles correspondants de l'IEC 60704-1:2010 de façon à établir le code d'essai pour les ventilateurs.

General Information

• Status: Published
• Publication Date: 22-Jan-2020
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 17.140.20 - Noise emitted by machines and equipment
• ICS: 23.120 - Ventilators. Fans. Air-conditioners
• Technical Committee: SC 59L - Small household appliances
• Drafting Committee: WG 2 - TC 59/SC 59L/WG 2
• Current Stage: PPUB - Publication issued
• Start Date: 10-Jan-2020
• Completion Date: 23-Jan-2020

Standards Content (Sample)

IEC 60704-2-7
®

Edition 2.0 2020-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Household and similar electrical appliances –
Test code for the determination of airborne acoustical noise –
Part 2-7: Particular requirements for fans

Appareils électrodomestiques et analogues –
Code d'essai pour la détermination du bruit aérien –
Partie 2-7: Exigences particulières pour les ventilateurs

IEC 60704-2-7:2020-01(en-fr)

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IEC 60704-2-7

®


Edition 2.0 2020-01




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Household and similar electrical appliances –

Test code for the determination of airborne acoustical noise –

Part 2-7: Particular requirements for fans




Appareils électrodomestiques et analogues –

Code d'essai pour la détermination du bruit aérien –


Partie 2-7: Exigences particulières pour les ventilateurs













INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 17.140.20; 23.120 ISBN 978-2-8322-7712-6




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

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

---------------------- Page: 3 ----------------------
– 2 – IEC 60704-2-7:2020 © IEC 2020
CONTENTS
FOREWORD . 3
1 Scope and object . 6
2 Normative references . 7
3 Terms and definitions . 8
4 Measurement methods and acoustical environments . 10
5 Instrumentation . 10
6 Operation and location of appliances under test . 10
7 Measurement of sound pressure levels . 12
8 Calculation of sound pressure and sound power levels . 13
9 Information to be recorded . 13
10 Information to be reported . 13
Annexes . 15
Annex B (normative) Test enclosure . 15
Bibliography . 15

Figure 101 – Measurement surface – hemisphere – with 10 microphone positions for
partition (wall and window) fans and for wall-mounted table fans . 14

Table 101 – Standard deviations of sound power levels . 7
Table 102 – Standard deviations for declaration and verification . 7

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IEC 60704-2-7:2020 © IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________

HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
TEST CODE FOR THE DETERMINATION OF
AIRBORNE ACOUSTICAL NOISE –

Part 2-7: Particular requirements for fans

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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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 60704-2-7 has been prepared by subcommittee 59L: Small
household appliances, of IEC technical committee 59: Performance of household and similar
electrical appliances.
This second edition cancels and replaces the first edition published in 1997. This edition
constitutes a technical revision.
This edition includes the following significant changes with respect to the previous edition:
a) it includes additional fan categories as defined in IEC 60879:2019 and IEC 60665:2018;
b) it includes standard deviations of sound power levels in 1.3;
c) a comparison method has been added;
d) the normative references have been updated (ISO 3744:2010 and ISO 3743-1:2010);
e) it has been adjusted with regard to IEC 60704-1:2010.

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– 4 – IEC 60704-2-7:2020 © IEC 2020
The text of this standard is based on the following documents:
CDV Report on voting
59L/168/CDV 59L/174/RVC

Full information on the voting for the approval of this 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 60704 series, published under the general title Household and
similar electrical appliances – Test code for the determination of airborne acoustical noise,
can be found on the IEC website.
This International Standard is to be used in conjunction with IEC 60704-1:2010, Household
and similar electrical appliances – Test code for the determination of airborne acoustical noise
– Part 1: General requirements.
NOTE When “Part 1” is mentioned in this standard, it refers to IEC 60704-1:2010.
The relevant text of Part 1 as amended by this standard establishes the test code for fans.
This Part 2-7 supplements or modifies the corresponding clauses in IEC 60704-1:2010, so as
to establish the test code for fans. When a particular subclause of Part 1 is not mentioned in
this Part 2-7, that subclause is applicable as far as reasonable. Where this standard states
"addition", "modification" or "replacement", the relevant requirements, test specifications or
explanatory matter in Part 1 should be adapted accordingly.
Subclauses, tables and figures that are numbered starting from 101 are additional to those in
Part 1.
Unless notes are in a new subclause or involve notes in Part 1, they are numbered starting
from 101, including those in a replaced clause or subclause.
Additional annexes are lettered AA, BB, etc.
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.

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IEC 60704-2-7:2020 © IEC 2020 – 5 –
INTRODUCTION
The measuring conditions specified in this Part 2-7 provide for sufficient accuracy in
determining the noise emitted and the comparison of the results of measurements taken by
different laboratories, whilst simulating as far as possible the practical use of household fans.
It is recommended to consider the determination of noise levels as part of a comprehensive
testing procedure covering many aspects of the properties and performance of household
fans.
NOTE As stated in the introduction to IEC 60704-1, this test code is concerned with airborne noise only.

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– 6 – IEC 60704-2-7:2020 © IEC 2020
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
TEST CODE FOR THE DETERMINATION OF
AIRBORNE ACOUSTICAL NOISE –

Part 2-7: Particular requirements for fans



1 Scope and object
This clause of Part 1 is applicable except as follows:
1.1 Scope
1.1.1 General
Replacement:
This document applies to electrical fans (including their accessories and their component
parts) for household and similar use, designed for AC or DC supply.
The motor, the impeller and their housing, if any, form a single unit.
These particular requirements apply to:
– conventional fans,
– table fans,
– pedestal fans,
– ceiling fans,
– bladeless fans,
– wall bracket fans,
– ceiling bracket fans,
– louver fans,
– tower fans,
– ventilating and partition ventilating fans.
This standard does not apply to:
– fans that are part of a ventilation system,
– fans designed exclusively for industrial purposes,
– fans that are part of an appliance (for example cooling fans),
– fans with additional functions (for example heating, humidifying).
Limitations for the use of this test code are given in the scope of IEC 60704-1.
1.1.2 Type of noise
Replacement:
The methods specified in ISO 3743-1, ISO 3743-2 and ISO 3744 can be used for measuring
noise emitted by fans.

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IEC 60704-2-7:2020 © IEC 2020 – 7 –
1.1.3 Size of source
Replacement:
The method specified in ISO 3744 is applicable to noise sources of any size. When applying
ISO 3743-1 and ISO 3743-2, care should be taken to ensure that the maximum size of the
appliance under test fulfils the requirements specified in 1.2 of ISO 3743-1:2010 and 1.3 of
ISO 3743-2:1994.
1.2 Object
Addition:
This document describes the determination of the noise emission of household fans in normal
operation at maximum speed. Other speeds can, in addition, be used. Requirements for the
declaration of noise emission values are not within the scope of this document.
The aim of this document is to give direction for measuring the noise in a room resulting from
the operation of a fan.
NOTE 101 For determining and verifying noise emission values declared in product specifications, see
IEC 60704-3.
1.3 Measurement uncertainty
Replacement:
The estimated values of standard deviations of sound power levels determined in accordance
with this document are given in Table 101:
Table 101 – Standard deviations of sound power levels
Standard deviation (dB)
σ (repeatability) σ (reproducibility)

r R
0,4 1,0

Addition:
1.101 Standard deviation for declaration and verification
For the purpose of determining and verifying declared noise emission values in accordance
with IEC 60704-3, the values in Table 102 apply:
Table 102 – Standard deviations for declaration and verification
Standard deviation (dB)
σ (production) σ (total) σ (reference)
P t M
0,5 to 1,0 1,0 to 1,4 1,5

2 Normative references
This clause of Part 1 is applicable except as follows:
Replacement:

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– 8 – IEC 60704-2-7:2020 © IEC 2020
ISO 3743-1:2010, Acoustics – Determination of sound power levels and sound energy levels
of noise sources using sound pressure – Engineering methods for small movable sources in
reverberant fields – Part 1: Comparison method for a hard-walled test room
ISO 3744:2010, Acoustics – Determination of sound power levels and sound energy levels of
noise sources using sound pressure – Engineering methods for an essentially free field over a
reflecting plane
Addition:
IEC 60704-1:2010, Household and similar electrical appliances – Test code for the
determination of airborne acoustical noise – Part 1: General requirements
3 Terms and definitions
This clause of Part 1 is applicable except as follows:
Addition:
3.101
conventional fan
comfort fan with a propeller having two or more blades, with free inlet and outlet of air
[SOURCE: IEC 60879:2019, 3.2]
3.102

tower fan
comfort fan for use directly on the floor having a vertically elongated design of the cross flow
type, tangential type or centrifugal type or impeller type with a free inlet and outlet of air
[SOURCE: IEC 60879:2019, 3.3]
3.103
bladeless fan
comfort fan of any type that is not fitted with a propeller
[SOURCE: IEC 60879:2019, 3.4]
3.104
ceiling fan
conventional fan provided with a device for suspension from the ceiling of a room so that the
blades rotate in a horizontal plane with the diameter of the blade not larger than 1800 mm
[SOURCE: IEC 60879:2019, 3.5]
3.105
table fan
comfort fan intended for use on a table
Note 1 to entry: Table fans have a maximum adjustable or non-adjustable height not greater than 1200mm
Note 2 to entry: Adjustment of height, position and oscillation can be possible.
Note 3 to entry: It can be a table fan or bracket-mounted fan for wall or ceiling mounting.
[SOURCE: IEC 60879:2019, 3.6, modified − Note 2 to entry and Note 3 to entry added]

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IEC 60704-2-7:2020 © IEC 2020 – 9 –
3.106
pedestal fan
comfort fan mounted on a pedestal of fixed or variable height
Note 1 to entry: Pedestal fans have a maximum adjustable height or non-adjustable height greater than 1 200 mm
Note 2 to entry: Adjustment of position and oscillation can be possible.
[SOURCE: IEC 60879:2019, 3.7, modified – Note 2 to entry added]
3.107
wall bracket fan
comfort fan for mounting on the wall
[SOURCE: IEC 60879:2019, 3.8]
3.108
ceiling bracket fan
comfort fan for mounting on the ceiling
[SOURCE: IEC 60879:2019, 3.9]
3.109
louvre fan
comfort fan having a moving louvre which provides a continuously changing multi-directional
air flow
[SOURCE: IEC 60879:2019, 3.10]
3.110
ventilating fan
fan intended to displace air either from one side of a partition to the other, or within a duct
installed either on the fan inlet or on the fan outlet or both
[SOURCE: IEC 60665:2018, 3.2]
3.111
partition ventilating fan
type A ventilating fan
ventilating fan installed in or upon the aperture of a partition in order to displace air from one
side of the partition to the other side, both the sides being free spaces
[SOURCE: IEC 60665:2018, 3.3]
3.112
free inlet partition ventilating fan
type B ventilating fan
ventilating fan with a direct inlet from free space and with ducted outlet
[SOURCE: IEC 60665:2018, 3.4]
3.113
free outlet partition ventilating fan
type C ventilating fan
ventilating fan with ducted inlet, and with direct outlet to free space
[SOURCE: IEC 60665:2018, 3.5]

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– 10 – IEC 60704-2-7:2020 © IEC 2020
3.114
fully ducted ventilating fan
type D ventilating fan
ventilating fan with ducted inlet and ducted outlet
[SOURCE: IEC 60665:2018, 3.6]
4 Measurement methods and acoustical environments
This clause of Part 1 is applicable except as follows:
4.2 Direct method
Addition:
If pure tone components are present in the noise emitted by the source, the estimated
standard deviation of the measured sound pressure levels in the special reverberation room
can increase. In such cases, additional microphone positions or source positions can be
necessary, such as those specified in ISO 3743-2.
4.3 Comparison method
Addition:
If pure tone components are present in the noise emitted by the source, the estimated
standard deviation of the measured sound pressure levels in the hard-walled test room or in
the special reverberation room can increase. In such cases, additional microphone positions
or source positions can be necessary, such as those specified in ISO 3743-1 or ISO 3743-2.
5 Instrumentation
This clause of Part 1 is applicable except as follows:
Addition:
The use of a windscreen is mandatory, and necessary corrections for changes in the
microphone sensitivity shall be added to the observed sound pressure levels.
6 Operation and location of appliances under test
This clause of Part 1 is applicable except as follows:
6.2 Supply of electricity and of water or gas
6.2.3
Not applicable.
6.2.4
Not applicable.

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IEC 60704-2-7:2020 © IEC 2020 – 11 –
6.4 Loading and operating of appliances during tests
6.4.1
Replacement:
Load and operation should simulate normal use. Fans that can be tilted during normal use
shall be located in the position with the highest emitted noise level, and the duration of the
measurement shall be at least 10 s.
Fans that can oscillate automatically shall operate when oscillating. In the case of oscillating
appliances, the A-weighted sound pressure level shall be averaged on at least one complete
cycle.
6.4.3
Not applicable.
6.5 Location and mounting of appliances
6.5.1
Addition:
Ceiling fans may be hung from a special support instead of from the ceiling. In this case, care
shall be taken to ensure that the means of suspension or clamping do not change the sound
output of the appliance. In order not to restrict the airflow, the distance between the lowest
edge of the appliance and the reflecting plane (usually the floor) shall be at least 1,5 m.
Alternatively, ceiling fans can be mounted in the reverse working position on the reflecting
plane, providing this does not affect sound radiation.
6.5.2
Not applicable.
6.5.3
Not applicable.
6.5.4
Replacement:
Partition (wall and window) fans shall be mounted in an opening made either:
– in a wall of the special reverberation test room; or
– on the second reflecting plane of the free field over a reflecting plane environment.
The height between the centre of the appliance and the floor shall be 1,5 m ± 0,05 m.
In all cases, care shall be taken to follow the instructions given by the manufacturer and to
avoid any structure-borne noise.
Care shall be taken to avoid any restriction of the airflow.
Attention shall be paid to avoid any difference of pressure between the rooms concerned (or
atmosphere), in order to avoid an unwanted load on the fan.

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– 12 – IEC 60704-2-7:2020 © IEC 2020
6.5.5
Not applicable.
6.5.7
Not applicable.
7 Measurement of sound pressure levels
This clause of Part 1 is applicable except as follows:
7.1 Microphone array, measurement surface and RSS location for essentially free-
field conditions over reflecting plane(s)
7.1.1
Addition:
This measurement surface shall be used for table, pedestal, louver, tower, bladeless, ceiling
bracket and ceiling fans. Table fans are placed on the floor.
This measurement surface shall not be used for wall bracket fans and window fans.
The use of a windscreen is mandatory.
7.1.2
Not applicable.
7.1.3
Not applicable.
7.1.4
Replacement:
For partition (wall and window) fans and wall-mounted table fans, the measurement surface is
a hemisphere, with 10 microphone positions as specified in Figure 101, centred in the
projection of the geometrical centre of the reference box on the vertical plane, the coordinate
system describing the microphone positions being located with the x- and y-axes in the
vertical reflecting plan and the z-axis horizontally perpendicular to it. The x-axis lies in the
horizontal central plane of the reference box. The front of the fan is directed towards the z-
axis.
2
The area of this measurement surface is S = 2πR .
The radius of the hemisphere is 1 m.
7.1.5
Not applicable.
7.1.6
Addition:

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IEC 60704-2-7:2020 © IEC 2020 – 13 –
This measurement surface shall be used for tall pedestal fans.
7.2 Microphone array and RSS location in hard-walled test rooms
Not applicable.
7.4 Measurements
7.4.4
Not applicable.
8 Calculation of sound pressure and sound power levels
This clause of Part 1 is applicable.
9 Information to be recorded
This clause of Part 1 is applicable except as follows:
9.7 Electric supply, water supply, etc.
9.7.3
Not applicable.
9.7.4
Not applicable.
10 Information to be reported
This clause of Part 1 is applicable, except as follows:
10.3 Test conditions for the appliance
10.3.4
Not applicable.
10.3.5
Not applicable.

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– 14 – IEC 60704-2-7:2020 © IEC 2020
Coordinates of microphone positions:
N° x/R y/R z/R
1 0 -0,99 0,15
2 0,86 0,50 0,15
3 -0,86 0,50 0,15
4 -0,77 -0,45 0,45
5 0,77 -0,45 0,45
6 0 0,89 0,45
7 -0,57 0,33 0,75
8 0 -0,66 0,75
9 0,57 0,33 0,75
10 0 0 1,0

Measurement surface area:
2
S = 2πR


Figure 101 – Measurement surface – hemisphere – with 10 microphone positions for
partition (wall and window) fans and for wall-mounted table fans

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IEC 60704-2-7:2020 © IEC 2020 – 15 –
Annexes
The annexes of Part 1 apply with the following exception:
Annex B
(normative)

Test enclosure
This annex of Part 1 is not applicable.

Bibliography
Addition:
IEC 60665:2018, A.C. ventilating fans and regulators for household and similar purposes –
Methods for measuring performance
IEC 60879:2019, Comfort fans and regulators for household and similar purposes – Methods
for measuring performance

___________

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– 16 – IEC 60704-2-7:2020 © IEC 2020
SOMMAIRE
AVANT-PROPOS . 17
INTRODUCTION . 19
1 Domaine d'application et objet . 20
2 Références normatives . 21
3 Termes et définitions . 22
4 Méthodes de mesure et environnements acoustiques . 24
5 Appareill
...