IEC 60034-9:2021

Rotating electrical machines - Part 9: Noise limits

IEC 60034-9:2021 specifies test methods for the determination of sound power level of rotating electrical machines and specifies maximum A-weighted sound power levels for factory acceptance testing of network-supplied, rotating electrical machines in accordance with lEC 60034-1, having methods of cooling according to lEC 60034-6 and degrees of protection according to lEC 60034-5, and having the following characteristics:
- standard design, either AC or DC, without additional special electrical, mechanical, or acoustical modifications intended to reduce the sound power level
- rated output from 1 kW (or kVA) up to and including 5 500 kW (or kVA)
- rated speed not greater than 3 750 min–1
This fifth edition cancels and replaces the fourth edition, published in 2003 and its amendment 1, published in 2007. This edition includes the following significant technical changes with respect to the previous edition:
a) In Table 2 and Table 3 cooling methods IC01, IC11, IC21 and IC31, IC71, IC81 are now covered.
b) This edition adds Table 3 for 60 Hz machines, whereas Table 2, which covers only 50 Hz machines, has no change in levels.
c) In Table 3, grade A is added to harmonize the highest levels seen in IEC and NEMA, whereas grade B was added to harmonize the lowest, more restrictive levels seen in IEC and NEMA.
d) The clause “Determination of noise increments caused by converter supply” has been shifted to Annex B and renamed “Information on typical noise increments caused by converter supply”.

Machines électriques tournantes - Partie 9: Limites de bruit

IEC 60034-9:2021 spécifie les méthodes d’essai pour la détermination du niveau de puissance acoustique des machines électriques tournantes et spécifie les niveaux maximaux de puissance acoustique pondérée A pour les essais de réception en usine des machines électriques tournantes alimentées par réseau conformes à l’IEC 60034-1, dont les modes de refroidissement sont conformes à l’IEC 60034-6 et les degrés de protection conformes à l’IEC 60034-5, et qui présentent les caractéristiques suivantes:
- conception normalisée, courant alternatif ou courant continu, sans modifications spéciales électriques, mécaniques ou acoustiques destinées à réduire le niveau de puissance acoustique
- puissance assignée de 1 kW (ou kVA) jusqu'à 5 500 kW inclus (ou kVA)
- vitesse assignée inférieure ou égale à 3 750 min–1
Cette cinquième édition annule et remplace la quatrième édition, parue en 2003 et son amendement 1, paru en 2007. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) Le Tableau 2 et le Tableau 3 couvrent désormais les méthodes de refroidissement IC01, IC11, IC21 et IC31, IC71, IC81.
b) La présente édition ajoute le Tableau 3 pour les machines de 60 Hz, tandis que le Tableau 2, qui ne couvre que les machines de 50 Hz, ne présente pas de modification de niveaux.
c) Dans le Tableau 3, l’ajout du degré A vise à harmoniser les niveaux les plus élevés définis par l’IEC et NEMA, tandis que l’ajout du degré B visait à harmoniser les niveaux plus faibles mais plus restrictifs également définis par l’IEC et NEMA.
d) L'article "Détermination de l’augmentation de bruit provoquée par l’alimentation du convertisseur" a été transféré dans l’Annexe B et renommé "Informations sur l’augmentation type de bruit provoquée par l’alimentation du convertisseur".

General Information

• Status: Published
• Publication Date: 13-Oct-2021
• ICS: 29.160.01 - Rotating machinery in general
• Technical Committee: TC 2 - Rotating machinery
• Drafting Committee: MT 2 - TC 2/MT 2
• Current Stage: PPUB - Publication issued
• Start Date: 05-Nov-2021
• Completion Date: 14-Oct-2021

Relations

• Revises: IEC 60034-9:2003 - Rotating electrical machines - Part 9: Noise limits
• Effective Date: 05-Sep-2023
• Revises: IEC 60034-9:2003/AMD1:2007 - Amendment 1 - Rotating electrical machines - Part 9: Noise limits
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60034-9 ®
Edition 5.0 2021-10
COMMENTED VERSION
INTERNATIONAL
STANDARD
colour
inside
Rotating electrical machines –
Part 9: Noise limits
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 60034-9 ®
Edition 5.0 2021-10
COMMENTED VERSION
INTERNATIONAL
STANDARD
colour
inside
Rotating electrical machines –

Part 9: Noise limits
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.160.01 ISBN 978-2-8322-4015-1

– 2 – IEC 60034-9:2021 CMV © IEC 2021
CONTENTS
FOREWORD . 3
INTRODUCTION . 2
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Methods of measurement . 8
5 Test conditions . 8
5.1 Machine mounting . 8
5.1.1 Precautions . 8
5.1.2 Resilient mounting . 9
5.1.3 Rigid mounting . 9
5.2 Test operating conditions . 9
6 Sound power level limits . 9
7 Determination of noise increments caused by converter supply .
7 Determination of sound pressure level . 10
8 Declaration and verification of sound power values. 12
Annex A (informative) Typical values for measurement surface index . 18
Annex B (informative) Information on typical noise increments caused by converter supply . 19
Bibliography . 22
List of comments . 23
Figure B.1 – Frequency spectrum of the currents at the output terminals of a 6‑pulse
block-type current-source converter f = 50 Hz . 19
Figure B.2 – Frequency spectrum of the voltages at the terminals of a type A
voltage-source converter (characterized by pronounced spikes close to the switching
frequency and its multiples) f = 50 Hz, f = 3 kHz . 19
1 s
Figure B.3 – Frequency spectrum of the voltages of a type B voltage-source converter
= 50 Hz, f
(characterized by a broad voltage spectrum without pronounced spikes) f
1 s
average = 4,5 kHz . 20
Table 1 – Maximum A-weighted sound power level, L in dB, at no-load (excluding
WA
motors according to Table 2 and Table 3) (Method of cooling, IC code, see IEC 60034-
6, Method of protection, IP code, see IEC 60034-5) . 14
Table 2 – Maximum A-weighted sound power level, LWA in dB, at no-load, 50 Hz,
sinusoidal supply (for single speed three-phase cage induction motors IC411, IC511,
IC611) . 15
Table 3 – Maximum A-weighted sound power level, L in dB, at no-load, 60 Hz,
WA
sinusoidal supply (for single speed three-phase cage induction motors). 16
Table 4 – Maximum Expected increase, over no-load condition, in A-weighted sound power
levels, ΔL in dB, for rated load condition (for motors according to Table 2 and Table 3) . 17
WA
Table A.1 – Typical values for measurement surface index for the conversion from sound
power level to sound pressure level based on using parallelepiped measurement surface
according to ISO 3744 . 18
Table B.1 – Resonance frequencies of vibration mode r . 20
Table B.2 – Increments of A-weighted noise values . 20

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –

Part 9: Noise limits
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.
This commented version (CMV) of the official standard IEC 60034-9:2021 edition 5.0
allows the user to identify the changes made to the previous IEC 60034-9:2003
+AMD1:2007 CSV edition 4.1. Futhermore, comments from IEC TC 2 experts are provided
to explain the reasons of the most relevant changes.
A vertical bar appears in the margin wherever a change has been made. Additions are in
green text, deletions are in strikethrough red text. Experts' comments are identified by a
blue-background number. Mouse over a number to display a pop-up note with the
comment.
This publication contains the CMV and the official standard. The full list of comments is
available at the end of the CMV.

– 4 – IEC 60034-9:2021 CMV © IEC 2021
IEC 60034-9 has been prepared by IEC technical committee 2: Rotating machinery. It is an
International Standard.
This fifth edition cancels and replaces the fourth edition, published in 2003 and its
amendment 1, published in 2007. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) In Table 2 and Table 3 cooling methods IC01, IC11, IC21 and IC31, IC71, IC81 are now
covered.
b) This edition adds Table 3 for 60 Hz machines, whereas Table 2, which covers only 50 Hz
machines, has no change in levels.
c) In Table 3, grade A is added to harmonize the highest levels seen in IEC and NEMA,
whereas grade B was added to harmonize the lowest, more restrictive levels seen in IEC
and NEMA.
d) The clause “Determination of noise increments caused by converter supply” has been
shifted to Annex B and renamed “Information on typical noise increments caused by
converter supply”
The text of this International Standard is based on the following documents:
FDIS Report on voting
2/2064/FDIS 2/2069/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
A list of all parts in the IEC 60034 series, published under the general title Rotating electrical
machines, can be found on the IEC website.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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INTRODUCTION
Acoustic quantities can be expressed in sound pressure terms or sound power terms. The use
of a sound power level, which can be specified independently of the measurement surface and
...

IEC 60034-9 ®
Edition 5.0 2021-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Rotating electrical machines –
Part 9: Noise limits
Machines électriques tournantes –
Partie 9: Limites de bruit
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International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

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IEC 60034-9 ®
Edition 5.0 2021-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Rotating electrical machines –

Part 9: Noise limits
Machines électriques tournantes –

Partie 9: Limites de bruit
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.160.01 ISBN 978-2-8322-1034-0

– 2 – IEC 60034-9:2021 © IEC 2021
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Methods of measurement . 8
5 Test conditions . 8
5.1 Machine mounting . 8
5.1.1 Precautions . 8
5.1.2 Resilient mounting . 9
5.1.3 Rigid mounting . 9
5.2 Test operating conditions . 9
6 Sound power level limits . 9
7 Determination of sound pressure level . 10
8 Declaration and verification of sound power values. 10
Annex A (informative) Typical values for measurement surface index . 16
Annex B (informative) Information on typical noise increments caused by converter
supply . 17
Bibliography . 20

Figure B.1 – Frequency spectrum of the currents at the output terminals of a 6‑pulse
block-type current-source converter f = 50 Hz . 17
Figure B.2 – Frequency spectrum of the voltages at the terminals of a type A
voltage-source converter (characterized by pronounced spikes close to the switching

frequency and its multiples) f = 50 Hz, f = 3 kHz . 17
1 s
Figure B.3 – Frequency spectrum of the voltages of a type B voltage-source converter
(characterized by a broad voltage spectrum without pronounced spikes) f = 50 Hz, f
1 s
average = 4,5 kHz . 18

Table 1 – Maximum A-weighted sound power level, L in dB, at no-load (excluding
WA
motors according to Table 2 and Table 3) (Method of cooling, IC code, see IEC 60034-
6, Method of protection, IP code, see IEC 60034-5) . 12
Table 2 – Maximum A-weighted sound power level, L in dB, at no-load, 50 Hz,
WA
sinusoidal supply (for single speed three-phase cage induction motors). 13
Table 3 – Maximum A-weighted sound power level, L in dB, at no-load, 60 Hz,
WA
sinusoidal supply (for single speed three-phase cage induction motors). 14
Table 4 – Expected increase, over no-load condition, in A-weighted sound power
levels, ΔL in dB, for rated load condition (for motors according to Table 2 and
WA
Table 3) . 15
Table A.1 – Typical values for measurement surface index for the conversion from
sound power level to sound pressure level based on using parallelepiped measurement
surface according to ISO 3744 . 16
Table B.1 – Resonance frequencies of vibration mode r . 18
Table B.2 – Increments of A-weighted noise values . 19

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –

Part 9: Noise limits
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.
IEC 60034-9 has been prepared by IEC technical committee 2: Rotating machinery. It is an
International Standard.
This fifth edition cancels and replaces the fourth edition, published in 2003 and its
amendment 1, published in 2007. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) In Table 2 and Table 3 cooling methods IC01, IC11, IC21 and IC31, IC71, IC81 are now
covered.
b) This edition adds Table 3 for 60 Hz machines, whereas Table 2, which covers only 50 Hz
machines, has no change in levels.
c) In Table 3, grade A is added to harmonize the highest levels seen in IEC and NEMA,
whereas grade B was added to harmonize the lowest, more restrictive levels seen in IEC
and NEMA.
– 4 – IEC 60034-9:2021 © IEC 2021
d) The clause “Determination of noise increments caused by converter supply” has
...