Rotating electrical machines - Part 30: Efficiency classes of single-speed, three-phase, cage-induction motors (IE-code)

IEC 60034-30:2008 specifies efficiency classes for single-speed, three-phase, 50 Hz and 60 Hz, cage-induction motors.

Machines électriques tournantes - Partie 30: Classes de rendement pour les moteurs à induction triphasés à cage, mono vitesse (Code IE)

La CEI 60034-30:2008 spécifie les classes de rendement pour les moteurs électriques à induction triphasés 50 Hz et 60 Hz à cage, mono vitesse.

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Status
Replaced
Publication Date
20-Oct-2008
Technical Committee
Drafting Committee
Current Stage
DELPUB - Deleted Publication
Completion Date
06-Mar-2014
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IEC 60034-30
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Rotating electrical machines –
Part 30: Efficiency classes of single-speed, three-phase, cage-induction motors
(IE-code)

Machines électriques tournantes –
Partie 30: Classes de rendement pour les moteurs à induction triphasés à cage,
mono vitesse (Code IE)

IEC 60034-30:2008

---------------------- Page: 1 ----------------------
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IEC 60034-30
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Rotating electrical machines –
Part 30: Efficiency classes of single-speed, three-phase, cage-induction motors
(IE-code)

Machines électriques tournantes –
Partie 30: Classes de rendement pour les moteurs à induction triphasés à cage,
mono vitesse (Code IE)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
Q
CODE PRIX
ICS 29.160 ISBN 978-2-88910-022-4
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – 60034-30 © IEC:2008
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.7
2 Normative references .7
3 Terms, definitions and symbols .8
3.1 Terms and definitions .8
3.2 Symbols .8
4 Fields of application (informative) .8
5 Efficiency .9
5.1 Determination.9
5.1.1 General .9
5.1.2 Rated voltages, rated frequencies and rated output .9
5.1.3 Auxiliary devices .10
5.2 Rating .10
5.3 Classification and marking.10
5.3.1 General .10
5.3.2 Efficiency classification.11
5.3.3 Motors below standard efficiency.11
5.3.4 Marking .11
5.4 Nominal efficiency limits .11
5.4.1 Interpolation .11
5.4.2 Nominal limits for Standard Efficiency (IE1) .12
5.4.3 Nominal limits for High Efficiency (IE2) .14
5.4.4 Nominal limits for Premium Efficiency (IE3) .15
Bibliography.17

Figure 1 – Allocation of the saving potential by installed motors in the industrial sector .5

Table 1 – IE-Efficiency classification.11
Table 2 – Interpolation coefficients (informative) .12
Table 3 – Nominal limits (%) for Standard Efficiency (IE1) 50 Hz .12
Table 4 – Nominal limits (%) for Standard Efficiency (IE1) 60 Hz .13
Table 5 – Nominal limits (%) for High Efficiency (IE2) 50 Hz .14
Table 6 – Nominal limits (%) for High Efficiency (IE2) 60 Hz .14
Table 7 – Nominal limits (%) for Premium Efficiency (IE3) 50 Hz.15
Table 8 – Nominal limits (%) for Premium Efficiency (IE3) 60 Hz.16

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60034-30 © IEC:2008 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ROTATING ELECTRICAL MACHINES –

Part 30: Efficiency classes of single-speed,
three-phase, cage-induction motors (IE-code)


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,
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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
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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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
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members of its technical committees and IEC National Committees for any personal injury, property damage or
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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60034-30 has been prepared by IEC technical committee 2:
Rotating machinery.
The text of this standard is based on the following documents:
FDIS Report on voting
2/1518/FDIS 2/1521/RVD

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 publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 60034 series, under the general title, Rotating electrical machines,
can be found on the IEC website.

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– 4 – 60034-30 © IEC:2008
A table of cross-references of all IEC technical committee 2 publications can be found in the
IEC technical committee 2 dashboard on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://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.

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60034-30 © IEC:2008 – 5 –
INTRODUCTION
This International Standard provides for the global harmonization of energy-efficiency classes
for electric motors.
Electric motor applications in industry consume between 30 % and 40 % of the generated
electrical energy worldwide. Improving efficiency of the complete drive system (i.e. motor and
adjustable-speed drives) including the application (or process) is therefore a major concern in
energy-efficiency efforts. The total energy saving potential of an optimized system is assumed
to be around 30 % to 60 %.
According to the findings of the IEA 7 July 2006 Motor Workshop, electric motors with
improved efficiency in combination with frequency converters can save about 7 % of the total
worldwide electrical energy. Roughly one quarter to one third of these savings come from the
improved efficiency of the motor. The remaining part results from system improvements.
Many different energy efficiency standards for cage induction motors are already in use
(NEMA, EPACT, CSA, CEMEP, COPANT, AS/NZS, JIS, GB and others) with new classes
currently being developed. It becomes increasingly difficult for manufacturers to design
motors for a global market and for customers to understand differences and similarities of
standards in different countries.
Motors from 0,75 kW up to 375 kW make up the vast majority of installed motor population
and are covered by this standard as shown in Figure 1.

Allocation of the saving potential by installed motors in the industrial sector
(installed capacity multiplied by the average efficiency improvement)
35 %
30 %
25 %
20 %
15 %
10 %
5 %
0 %
0,75 kW 4 kW 10 kW 30 kW 70 kW 130 kW
< 500 kW
< 0,75 kW to to to to to to
< 4 kW < 10 kW < 30 kW < 70 kW < 130 kW < 500 kW
Sources: 1. SAVE-Report "Improving the Penetration of Energy Efficient Motors and Drives" (1996)
2. CEMEP calculations
IEC  1823/08

Figure 1 – Allocation of the saving potential by installed motors in the industrial sector
In some countries smaller motors are included in energy efficiency regulations. Most of these
motors are not three-phase, cage-induction machines. Also they typically do not run
continuously so their energy saving potential is rather limited.
In some countries 8-pole motors are included in energy efficiency regulations. However, their
market share is already very low (1 % or less). Due to increasing acceptance of variable-
speed drives and the low cost associated with 4- and 6-pole standard motors it is expected
that 8-pole motors will even further disappear from the general market in the future.
Therefore, this standard does not include provisions for 8-pole motors.

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– 6 – 60034-30 © IEC:2008
For a given output power and frame size it is generally easier to reach a high motor efficiency
when the motor is designed for and operated at 60 Hz mains supply frequency rather than at
50 Hz.
NOTE 1 As the utilization and size of motors are related to torque rather than power the theoretical output power
increases linearly with speed, i.e. by 20 % from 50 Hz to 60 Hz.
I²R winding-losses are dominant especially in small and medium sized induction motors. They basically remain
constant for 50 Hz and 60 Hz as long as the torque is kept constant. Although windage, friction and iron losses
increase with frequency, they play a minor role in these motors. Therefore, at 60 Hz, the losses increase less than
the 20 % output-power increase compared to 50 Hz and the efficiency improves.
In practice, both 60 Hz and 50 Hz output power designations should conform to standard power levels in
accordance with IEC 60072-1 and local standards like EN 50347. Therefore, an increased rating of motor power by
20 % is not always possible. However, the general advantage of 60 Hz still applies if the motor design is optimized
for the respective supply frequency rather than just re-rated.
The difference in efficiency between 50 Hz and 60 Hz varies with the number of poles and the size of the motor. In
general, the 60 Hz efficiency of three-phase, cage-induction motors in the output power range from 0,75 kW up to
375 kW is between 2,5 % to less than 0,5 % points greater when compared to the 50 Hz efficiency. Only large 2-
pole motors may experience a reduced efficiency at 60 Hz due to their high share of iron, windage and friction
losses.
In this standard, the nominal 50 Hz limits of Standard (IE1) and High Efficiency (IE2) are
based on the CEMEP-EU EFF2 and EFF1 limits respectively. However, they have been
adjusted to take the different test procedures into account (CEMEP: Additional load losses
P flat 0,5 % of input power; in this standard P is determined from test).
LL LL
The nominal 50 Hz limits for Premium Efficiency (IE3) are set with the losses about 15 % to
20 % lower compared to the limits for High Efficiency (IE2).
The nominal 60 Hz limits for Standard Efficiency (IE1) are identical to Brazilian regulations.
The nominal 60 Hz limits for High Efficiency (IE2) and for Premium Efficiency (IE3) are
identical to US American EPAct regulations.
A new Super-Premium class (IE4) is envisaged for future editions of this standard.
It is not expected that all manufacturers will produce motors for all efficiency classes or all
ratings for a given class.
Users should select the efficiency class in accordance with the application depending on the
actual operating hours. It may not be energy efficient to select High- or Premium-Efficiency
motors for intermittent or short-time duty.
NOTE 2 An application guide with more details is planned to be released as an IEC publication soon.
In order to achieve a significant market share it is essential for high-efficiency motors to meet
national/regional standards for assigned output powers in relation to mechanical dimensions
(frame-size, flanges, etc.). There are a number of national/regional frame assignment
standards (EN 50347, JISC 4212, NBR 7094, NEMA MG1, SANS 1804 and others) but there
is no IEC standard. As this standard (IEC 60034-30) defines energy-efficiency classes
independent of dimensional constraints it may not be possible in all markets to produce
motors with higher efficiency classes and maintain the mechanical dimensions of the
national/regional standards.
Regulators should consider the above constraints as well as the field of applications as
detailed in Clause 4 when assigning minimum energy-efficiency performance standards
(MEPS).

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60034-30 © IEC:2008 – 7 –
ROTATING ELECTRICAL MACHINES –

Part 30: Efficiency classes of single-speed,
three-phase, cage-induction motors (IE-code)



1 Scope
This part of IEC 60034 specifies efficiency classes for single-speed, three-phase, 50 Hz and
60 Hz, cage-induction motors that:
• have a rated voltage U up to 1 000 V;
N
NOTE The standard also applies to motors rated for two or more voltages and/or frequencies.
• have a rated output P between 0,75 kW and 375 kW;
N
• have either 2, 4 or 6 poles;
• are rated on the basis of either duty type S1 (continuous duty) or S3 (intermittent periodic
duty) with a rated cyclic duration factor of 80 % or higher;
• are capable of operating direct on-line;
• are rated for operating conditions in accordance with IEC 60034-1, Clause 6.
Motors with flanges, feet and/or shafts with mechanical dimensions different from
IEC 60072-1 are covered by this standard.
Geared motors and brake motors are covered by this standard although special shafts and
flanges may be used in such motors.
Excluded are:
• Motors made solely for converter operation in accordance with IEC 60034-25.
• Motors completely integrated into a machine (for example pump, fan and compressor) that
cannot be tested separately from the machine.
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 60034-1, Rotating electrical machines – Part 1: Rating and performance
IEC 60034-2-1, Rotating electrical machines – Part 2-1: Standard methods for determining
losses and efficiency from tests (excluding machines for traction vehicles)
IEC 60034-6, Rotating electrical machines – Part 6: Methods of cooling (IC Code)
IEC 60072-1, Dimensions and output series for rotating electrical machines – Part 1: Frame
numbers 56 to 400 and flange numbers 55 to 1080

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– 8 – 60034-30 © IEC:2008
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60034-1 and the
following apply.
3.1.1
brake motor
a motor equipped with an electro-mechanical brake unit operating directly on the motor shaft
without couplings
3.1.2
geared motor
a motor directly attached to a gearbox without couplings (i.e. the first gear wheel is fixed to
the motor shaft)
3.1.3
pump motor
a motor directly attached to a pump without couplings (i.e. the impeller is fixed to the motor
shaft)
3.1.4
average efficiency
the average efficiency value for a motor population of the same design and rating
3.1.5
nominal efficiency
the efficiency value required to meet a certain efficiency class according to the efficiency
tables in this standard
3.1.6
rated efficiency
the efficiency value assigned by the manufacturer, equal to the nominal efficiency value or
higher
3.2 Symbols
η is the nominal efficiency, %
n
η is the rated efficiency, %
N
f is the rated frequency, Hz
N
–1
n is the rated speed, min
N
P is the rated output power, kW
N
T is the rated output torque, Nm
N
U is the rated voltage, V
N
4 Fields of application (informative)
Motors covered by this standard may be used in variable-speed drive applications (see
IEC 60034-17). In such applications the rated efficiency of the motor should not be assumed
to apply due to increased losses from the harmonic-voltage content of the power supply.
Motors with cooling methods other than IC0Ax, IC1Ax, IC2Ax, IC3Ax or IC4Ax (see
IEC 60034-6) may not be able to achieve the higher efficiency classes specification.

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60034-30 © IEC:2008 – 9 –
In some countries, motors are built for a restricted space (high-output design, i.e. smaller
frame sizes than usual in national standards). These motors are covered by this standard.
However, as a result of the small frame-size they may not be able to achieve the higher
efficiency classes specification.
Motors specifically built for operation in explosive environments according to IEC 60079-0 are
covered by this standard. However, as a result of safety requirements and certain design
constraints of explosion proof motors (like increased air-gap, reduced starting current,
enhanced sealing and others) some may not be able to achieve higher efficiency
classifications.
NOTE 1 Due to the required certification processes additional time and cost may be necessary to achieve the
higher efficiency ratings for some of these motors.
Motors specifically designed
• for special requirements of the driven machine (e.g. heavy starting duty, special
torque stiffness and/or breakdown torque characteristics, large number of
start/stop cycles, very low rotor inertia);
• for special characteristics of the grid supply (e.g. limited starting current, high
tolerances of voltage and/or frequency);
• for special ambient conditions (e.g. very high or low ambient temperature; smoke
extraction motors, high altitudes of installation),
may not be able to achieve higher efficiency classifications.
NOTE 2 Regulators should consider the above constraints when assigning national minimum energy efficiency
performance standards (MEPS).
5 Efficiency
5.1 Determination
5.1.1 General
The efficiency shall be determined at rated output power P , rated voltage U and rated
N N
frequency f .
N
Efficiency and losses shall be determined in accordance with IEC 60034-2-1.
For IE1 (standard efficiency) and motors below standard efficiency, test methods associated
with low and medium uncertainty are acceptable. The selected test method shall be stated in
the documentation of the motor.
For all higher energy efficiency levels only methods associated with low uncertainty shall be
acceptable.
5.1.2 Rated voltages, rated frequencies and rated output
Motors rated for an extended voltage tolerance (for example 400 V ±10 %) shall be assigned
a single rated efficiency and rated efficiency-class (IE-code), i.e. the extended tolerance shall
be disregarded.
Motors with more than one rated voltage/frequency/output-power combination may be
assigned a rated efficiency and a rated efficiency-class (IE-code) for each rated
voltage/frequency/output combination.
However, as a minimum the lowest efficiency value and the associated IE-code (of all rated
voltage/frequency/output combinations) shall always be printed on the rating plate.

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– 10 – 60034-30 © IEC:2008
All efficiency values and associated IE-codes shall be available in the product documentation
(catalogue or operating instructions).
NOTE For example in Japan the rating combination “200 V/50 Hz – 200 V/60 Hz – 220 V/60 Hz” is commonly
used and in Europe the rating combination “380 V/50 Hz – 400 V/50 Hz – 415 V/50 Hz – 460 V/60 Hz” is
sometimes used. For these examples there will be three or four efficiency ratings and there may be several
different IE-codes.
Rated voltage/frequency combinations of the same magnetic flux and output-power, for
example 230/400 V (delta/star) or 230/460 V (double-star/star), shall have only one rated
efficiency and efficiency-class (IE-code).
5.1.3 Auxiliary devices
Some electric motors covered by this standard may be equipped with auxiliary devices like
shaft seals, external fans, mechanical brakes, back-stops, speed sensors, tacho-generators,
etc. in various combinations.
However, as long as these auxiliary devices are not an integral part of the motor construction,
the determination of efficiency in all possible combinations is not practical. Tests for efficiency
of such modified standard motors shall be performed on basic motors without auxiliary
devices installed.
Geared motors and pump motors are often standard motors equipped with shaft seals to
prevent ingress of oil or water into the motor. The seals are therefore considered a feature of
the gearbox or pump and consequently the efficiency of these motors shall be determined
without the seals installed.
5.2 Rating
Variations in materials, manufacturing processes, and testing result in motor-to-motor
efficiency variations for a given motor design; the full-load (rated output) efficiency for a large
population of motors of a single design is not a unique value but rather a band of efficiency.
Therefore, the rated output energy-efficiency limits given in this standard are nominal.
The efficiency declared by the manufacturer on the rating plate (rated efficiency) shall be
greater or equal to the nominal efficiency as defined in this standard (according to the
efficiency class (IE-code) on the rating plate).
The full-load efficiency of any individual motor, when tested at rated voltage and frequency,
shall not be less than the rated efficiency minus the tolerance on efficiency in
...

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