IEC 60034-12:2024

Rotating electrical machines - Part 12: Starting performance of single-speed three-phase cage induction motors

IEC 60034-12:2024 specifies the parameters for eight designs of starting performance of single-speed three-phase 50 Hz or 60 Hz cage induction motors in accordance with IEC 60034‑1 that:
- have a rated voltage up to 1 000 V;
- are intended for direct-on-line or star-delta starting;
- are rated on the basis of duty type S1;
- are constructed to any degree of protection as defined in IEC 60034-5 and explosion protection.
This document also applies to dual voltage motors provided that the flux saturation level is the same for both voltages. This fourth edition cancels and replaces the third edition published in 2016. Aligned with the requirements for explosion protected motors from TC31 WG27
- new clause on methods for measuring locked-rotor current and torque;
- new informative annex on the general current and torque characteristics with locked rotor;
- new informative annex on correction of voltage and frequency;
- aligned with the requirements for explosion protected motors from TC31 WG27.

Machines électriques tournantes - Partie 12: Caractéristiques de démarrage des moteurs triphasés à induction à cage à une seule vitesse

L'IEC 60034-12:2024 spécifie les paramètres de huit conceptions de caractéristiques de démarrage de moteurs triphasés à induction à cage à une seule vitesse fonctionnant à 50 Hz ou 60 Hz conformes à l'IEC 60034-1, qui:
- ont des tensions assignées jusqu'à 1 000 V;
- sont prévus pour démarrage direct ou étoile-triangle;
- sont dimensionnés pour le service type S1;
- peuvent avoir n'importe quel degré de protection tel qu'il est défini dans l'IEC 60034-5 et incluant les protections contre les explosions.
Ce document s'applique également aux moteurs bitension à condition que le niveau de saturation du flux soit le même aux deux tensions. Cette quatrième édition annule et remplace la troisième édition parue en 2016. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- aligné sur les exigences du CE 31, GT 27, concernant les moteurs antidéflagrants;
- nouvel article relatif aux méthodes de mesure du courant et du couple à rotor bloqué;
- nouvelle annexe informative relative aux caractéristiques générales de courant et de couple à rotor bloqué;
- nouvelle annexe informative relative à la correction de la tension et de la fréquence.

General Information

• Status: Published
• Publication Date: 21-May-2024
• ICS: 29.160.01 - Rotating machinery in general
• Technical Committee: TC 2 - Rotating machinery
• Drafting Committee: WG 12 - TC 2/WG 12
• Current Stage: PPUB - Publication issued
• Start Date: 18-Apr-2024
• Completion Date: 22-May-2024

Relations

• Revises: IEC 60034-12:2016 - Rotating electrical machines - Part 12: Starting performance of single-speed three-phase cage induction motors
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60034-12 ®
Edition 4.0 2024-05
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Rotating electrical machines –
Part 12: Starting performance of single-speed three-phase cage induction
motors
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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IEC 60034-12 ®
Edition 4.0 2024-05
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Rotating electrical machines –
Part 12: Starting performance of single-speed three-phase cage induction
motors
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.160.01 ISBN 978-2-8322-8990-7

– 2 – IEC 60034-12:2024 RLV © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Symbols . 8
5 Designation . 9
5.1 General . 9
5.2 Design N . 9
5.3 Design NE . 9
5.4 Designs NY and NEY . 9
5.5 Design H . 9
5.6 Design HE . 9
5.7 Designs HY and HEY . 10
6 Design N requirements . 10
6.1 Torque characteristics . 10
6.2 Locked rotor current and apparent power . 10
6.3 Starting requirements . 10
7 Design NE starting requirements . 11
8 Designs NY and NEY starting requirements . 11
9 Design H requirements . 11
9.1 Starting torque . 11
9.2 Locked rotor current and apparent power . 11
9.3 Starting requirements . 11
10 Design HE starting requirements . 12
11 Designs HY and HEY starting requirements . 12
12 Determination of current and torque from measurement. 12
12.1 Locked-rotor current and locked-rotor torque . 12
12.2 Breakdown torque . 12
12.3 Torque-speed curve and current-speed curve . 13
12.3.1 General . 13
12.3.2 Torque-speed and current-speed curves from direct measurement
(method a) . 13
12.3.3 Torque-speed and current-speed curves from acceleration (method b) . 13
12.3.4 Torque-speed and current-speed curves from measured input power
(method c) . 14
12.4 Correction of data for tests performed at reduced voltage and/or other than
rated frequency . 14
Annex A (informative) Current and torque characteristics with locked rotor . 20
Annex B (informative) Correction method for test done on reduced voltage . 24
Bibliography . 25

Figure A.1 – Locked-rotor current in multiples of rated current versus time . 20
Figure A.2 – Locked-rotor torque in multiples of rated torque versus time . 21
Figure A.3 – Locked-rotor torque in cNm versus rotor position in °; left: preferable
number of rotor slots, right: less preferable number of rotor slots . 21

Figure A.4 – Locked-rotor torque in cNm versus rotor position in ° . 22
Figure A.5 – Time -courses (in s) of rotational speed (upper left), torque (lower left),
phase voltage (upper right) and phase current (lower right) during a star-delta start-up . 23

Table 1 – Minimum values of torques for design N . 15
Table 2 – Maximum values of locked rotor apparent power for designs N and H . 16
Table 3 – Maximum values of locked rotor apparent power for designs NE and HE . 16
Table 4 – External moment of inertia (J) . 17
Table 5 – Minimum values of torques for design H . 18
Table 6 – Minimum values of torques for design N motors with type of protection 'Ex
eb – increased safety' . 18
Table 7 – External moment of inertia (J) for motors with type of protection 'Ex eb –
increased safety' . 19

– 4 – IEC 60034-12:2024 RLV © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –

Part 12: Starting performance of single-speed
three-phase cage induction motors

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.
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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.
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This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC 60034-12:2016. A vertical bar appears in the margin
wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
IEC 60034-12 has been prepared by IEC technical committee 2: Rotating machinery. It is an
International Standard.
This fourth edition cancels and replaces the third edition published in 2016. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
Clause or
Change
subclause
Table 6 Aligned with the requirements for explosion protected motors from TC31 WG27
12 New clause on methods for measuring locked-rotor current and torque
Annex A New informative annex on the general current and torque characteristics with locked
rotor
Annex B New informative annex on correction of voltage and frequency

The text of this International Standard is based on the following documents:
...

IEC 60034-12 ®
Edition 4.0 2024-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Rotating electrical machines –
Part 12: Starting performance of single-speed three-phase cage induction
motors
Machines électriques tournantes –
Partie 12: Caractéristiques de démarrage des moteurs triphasés à induction à
cage à une seule vitesse
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

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IEC 60034-12 ®
Edition 4.0 2024-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Rotating electrical machines –

Part 12: Starting performance of single-speed three-phase cage induction

motors
Machines électriques tournantes –

Partie 12: Caractéristiques de démarrage des moteurs triphasés à induction à

cage à une seule vitesse
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.160.01  ISBN 978-2-8322-8544-2

– 2 – IEC 60034-12:2024 © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Symbols . 8
5 Designation . 9
5.1 General . 9
5.2 Design N . 9
5.3 Design NE . 9
5.4 Designs NY and NEY . 9
5.5 Design H . 9
5.6 Design HE . 9
5.7 Designs HY and HEY . 10
6 Design N requirements . 10
6.1 Torque characteristics . 10
6.2 Locked rotor current and apparent power . 10
6.3 Starting requirements . 10
7 Design NE starting requirements . 11
8 Designs NY and NEY starting requirements . 11
9 Design H requirements . 11
9.1 Starting torque . 11
9.2 Locked rotor current and apparent power . 11
9.3 Starting requirements . 11
10 Design HE starting requirements . 12
11 Designs HY and HEY starting requirements . 12
12 Determination of current and torque from measurement. 12
12.1 Locked-rotor current and locked-rotor torque . 12
12.2 Breakdown torque . 12
12.3 Torque-speed curve and current-speed curve . 13
12.3.1 General . 13
12.3.2 Torque-speed and current-speed curves from direct measurement
(method a) . 13
12.3.3 Torque-speed and current-speed curves from acceleration (method b) . 13
12.3.4 Torque-speed and current-speed curves from measured input power
(method c) . 14
12.4 Correction of data for tests performed at reduced voltage and/or other than
rated frequency . 14
Annex A (informative) Current and torque characteristics with locked rotor . 20
Annex B (informative) Correction method for test done on reduced voltage . 24
Bibliography . 25

Figure A.1 – Locked-rotor current in multiples of rated current versus time . 20
Figure A.2 – Locked-rotor torque in multiples of rated torque versus time . 21
Figure A.3 – Locked-rotor torque in cNm versus rotor position in °; left: preferable
number of rotor slots, right: less preferable number of rotor slots . 21

Figure A.4 – Locked-rotor torque in cNm versus rotor position in ° . 22
Figure A.5 – Time -courses (in s) of rotational speed (upper left), torque (lower left),
phase voltage (upper right) and phase current (lower right) during a star-delta start-up . 23

Table 1 – Minimum values of torques for design N . 15
Table 2 – Maximum values of locked rotor apparent power for designs N and H . 16
Table 3 – Maximum values of locked rotor apparent power for designs NE and HE . 16
Table 4 – External moment of inertia (J) . 17
Table 5 – Minimum values of torques for design H . 18
Table 6 – Minimum values of torques for design N motors with type of protection 'Ex
eb – increased safety' . 18
Table 7 – External moment of inertia (J) for motors with type of protection 'Ex eb –
increased safety' . 19

– 4 – IEC 60034-12:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ROTATING ELECTRICAL MACHINES –

Part 12: Starting performance of single-speed
three-phase cage induction motors

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
...