IEC/TC 2 - IEC_TC_2

IEC 60034-12:2024 is available as IEC 60034-12:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.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.

IEC 60136:2024 applies primarily to brushes and brush-holders for cylindrical commutators and slip rings for electrical rotating machines. Some clauses of this document may cover other configurations, such as flat commutators or plain disks. It defines the dimensions of brushes and their components, together with their tolerances: - dimensions of brush block (t, a, r), - angles α and β, - chamfer, - flexibles (shunts), - standard terminals. It also covers the conventional designation of principal dimensions, the marking of brushes and the testing methods for the qualification of brushes after their manufacturing (except the brush grade material, covered by IEC 60413). This third edition cancels and replaces the second edition published in 1986 and Amendment 1:1995. This edition constitutes a technical revision. Please refer to the Foreword of the document for a comprehensive listing of the changes with respect to the previous edition.

IEC 60034-2-1:2024 is available as IEC 60034-2-1:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60034-2-1:2024 is intended to establish methods of determining efficiencies from tests, and also to specify methods of obtaining specific losses. This document applies to DC machines and to AC synchronous and induction machines of all sizes within the scope of IEC 60034-1 rated for mains operation. These methods may be applied to other types of machines such as rotary converters, AC commutator motors and single-phase induction motors. This third edition cancels and replaces the second edition of IEC 60034-2-1 published in 2014. This edition includes the following significant technical changes with respect to the previous edition: - Harmonization of layout and requirements with IEC 60034-2-2 and IEC 60034-2-3.

IEC 60034-2-3:2024 specifies test methods and an interpolation procedure for determining losses and efficiencies of converter-fed motors. The motor is then part of a variable frequency power drive system (PDS) as defined in IEC 61800‑9‑2. This document also specifies procedures to determine motor losses at any load point (torque, speed) within the constant flux range (constant torque range, base speed range), the field weakening range and the overload range based on determination of losses at seven standardized load points. This procedure is applicable to any variable speed AC motor (induction and synchronous) rated according to IEC 60034-1 for operation on a variable frequency and variable voltage power supply. This second edition cancels and replaces the first edition of IEC 60034-2-3 published in 2020. This edition includes the following significant technical changes with respect to the previous edition: - Harmonization of requirements and procedures with IEC 60034-2-1. - Extension of the interpolation procedure to the field weakening range.

IEC 60034-2-2:2024 applies to large rotating electrical machines and establishes additional methods of determining separate losses and to define an efficiency supplementing IEC 60034‑2‑1. These methods apply when full-load testing is not practical and results in a greater uncertainty. The specific methods described are: - Calibrated-machine method. - Retardation method. - Calorimetric method. - Summation of losses for permanent magnet excited synchronous machines. This second edition cancels and replaces the first edition published in 2010. This edition includes the following significant technical changes with respect to the previous edition: - Layout and procedures aligned with IEC 60034-2-1 and IEC 60034-2-3. - Annex A added: an informative procedure for the summation of losses for large permanent-magnet excited synchronous machines.

IEC 60034-30-3:2024 specifies efficiency classes for fixed-speed three-phase high-voltage cage induction motors in accordance with IEC 60034-1 that - have a rated voltage exceeding 1 000 V, but not exceeding 11 kV; - have a rated power from 200 kW to 2 000 kW; This document provides the global harmonization of energy-efficiency classes of three-phase cage induction motors with rated voltage above 1 000 V that are rated for direct online starting and fixed-speed operation at a 50 Hz or 60 Hz supply with sinusoidal voltage.

IEC 60034-27-2:2023 deals with on-line PD measurements and provides a common basis with standardized procedures if possible for: - measuring techniques and instruments; - the arrangement of the installation; - normalization and sensitivity assessment; - measuring procedures; - noise reduction; - the documentation of results; - the interpretation of results; with respect to partial discharge on-line measurements on the stator winding insulation of non‑converter driven rotating electrical machines with rated voltage of 3 kV and up. This document covers PD measuring systems and methods detecting electrical PD signals. The same measuring devices and procedures can also be used to detect electrical sparking and arcing phenomena.

This part of IEC 60034 deals with the general guidelines for functional evaluation of electrical insulation systems, used or proposed to be used in rotating electrical machines within the scope of IEC 60034-1, in order to qualify them.

IEC 60276:2018 applies to carbon brushes for electrical machinery. This edition applies only to carbon brushes for commutators and slip-rings in rotating machines. Terms and definitions are relative to the brush construction (references 100’s to 500’s and parts of 900’s) and to the markings when operating on a rotating machine (references 600’s to 800’s). This new edition includes the following significant technical changes with respect to the previous edition:  
Some nomenclature has been deleted or added, whereas remaining definitions have been detailed and clarified, to reflect the technical evolution since 1987.
Additional definitions have been included to address the request for reviewing this standard, in particular nomenclature of commutator/slip-rings markings, brush markings and commutation sparks codes.

The contents of the corrigendum of December 2020 have been included in this copy.

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”.

This document is applicable for the majority of rotating electrical machines for industrial purposes within the dimension range and output powers: Foot- mounted: shaft heights: 56mm to 400mm Flange- mounted: pitch circle diameter of flange: 55mm to 1080mm It specifies the fixing dimension, shaft extension dimensions and the assignment of output powers and frame sizes.

IEC 60034-7:2020 specifies the IM Code, a classification of types of construction, mounting arrangements and the terminal box position of rotating electrical machines. Two systems of classification are provided as follows: - Code I: An alpha-numeric designation applicable to machines with end-shield bearing(s) and only one shaft extension - Code II: An all-numeric designation applicable to a wider range of types of machines including types covered by Code I. This third edition cancels and replaces the second edition, published in 1992, and its Amendment 1:2000. The main technical changes with regard to the previous edition are as follows: - note on twin motors added - reference to 4.3 instead of duplication of text - new subclause on marking of shaft inclination or declination.

This part of IEC 60034 applies to three-phase salient-pole synchronous generators and synchronous motor-generators for hydraulic turbine and pump-turbine applications, that have rated frequency of 50 Hz or 60 Hz, rated output of 10 MVA and above, pole pair number 3 and above, and rated voltage of 6 kV and above. This document supplements basic requirements for rotating machines given in IEC 60034-1.

This part of IEC 60034-18 describes qualification procedures for the evaluation of electrical endurance of insulation systems for use in rotating electrical machines using form-wound windings. The test procedures are comparative in nature, such that the performance of a candidate insulation system is compared to that of a reference insulation system with proven service experience. If no reference system is available, the diagram in Annex A is available for use. The qualification procedures of inverter duty insulation system for form-wound windings can be found in IEC 60034-18-42 or IEC 60034-18-41.

This part of IEC 60034 covers the procedures necessary to ensure the satisfactory repair, overhaul, and reclamation of all types and sizes of rotating electrical machines covered by the IEC 60034 series. The standard creates a generic industry procedure covering common aspects of a complete repair. The scope of work depends on the machine type, rating, condition, and the importance of plant reliability and safety. It includes - determining cause of failure, where necessary; - determining the extent of repair, as applicable; - defining revised performance, operating and ambient conditions, if required; - reviewing the original design, and upgrading the specification of the design, if required; - proving the quality and performance of the repaired machine, maintaining or improving the rated energy efficiency; - ensuring environmental considerations are taken into account. This document does not supersede the requirements prescribed in IEC 60079-19 or elsewhere concerning the repair and overhaul for machines used in explosive atmospheres. Machines for special applications such as hermetic, submersible, nuclear, hydrogen cooled machines, military, aviation and traction motors might have additional requirements, which are the subject of agreement between the service facility and user. This document is not intended to take the place of the original machine manufacturer’s instructions and recommendations. Re-designs and performance changes requiring machine designer input are beyond the scope of this document.

This part of IEC 60034 provides recommended test procedures for the measurement of insulation resistance and polarization index of stator and rotor winding insulation of rotating electrical machines. This document recommends minimum acceptable values of insulation resistance and polarization index of winding insulation valid for fully processed low and high voltage AC and DC rotating electrical machines with a rated power of 750 W or higher.

NEW!IEC 60034-14:2018 is available as IEC 60034-14:2018 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60034-14:2018 specifies the factory acceptance vibration test procedures and vibration limits for certain electrical machines under specified conditions, when uncoupled from any load or prime mover. It is applicable to DC and three-phase AC machines, with shaft heights 56 mm and higher and a rated output up to 50 MW, at operational speeds from 120 min–1 up to and including 15 000 min–1. This new edition includes the following significant technical changes with respect to the previous edition: - Improved explanation of the definition “free suspension”. - Addition of an alternative method of rigid mount - Definition of an improved option for shaft key.

This part of IEC 60034 provides a common basis for: - measuring techniques and instruments; - the arrangement of test circuits; - normalization and testing procedures; - noise reduction; - the documentation of test results; - the interpretation of test results, with respect to partial discharge off-line measurements on the winding insulation of rotating electrical machines. The measurement methods described in this document are applicable to stator windings of machines with or without conductive slot coating and to the stator windings of machines made with form wound or random wound windings. In special cases like high voltage rotor field windings, this document is applicable as well. The measurement methods are applicable when testing with alternating sinusoidal voltages from 0,1 Hz up to 400 Hz. Interpretation guidelines are given in this document and are applicable only if all the following requirements are fulfilled: - Measurements performed with power frequency of 50 Hz or 60 Hz, or when testing with power supply within a frequency range of 45 Hz to 65 Hz. - Form wound windings and winding components such as bars and coils. - Winding with conductive slot coating. This is usually valid for machines with voltage rating of 6 kV and higher. For machines with random wound windings, form-wound windings without conductive slot coating, and testing at frequencies differing from power frequencies, the interpretation guidelines are not applicable. The testing procedures for off-line PD-measurements of this document can be used for assessing the uniform quality of manufacturing or/and the trending of these kind of windings as well as converter driven machine windings. NOTE Testing of low voltage machines with so called Type I insulation systems is defined in reference [10]1. Testing procedures for qualification of converter driven high voltage machines with so called Type II insulation systems are dealt with in IEC 60034-18-42 (in addition to the optional electric tests described therein).

IEC 60034-4-1:2018 applies to three-phase synchronous machines of 1 kVA rating and larger and describes methods intended to be used for machines having an excitation winding with slip-rings and brushes for their supply. Synchronous machines with brushless excitation require special effort for some of the tests. For machines with permanent magnet excitation, there is a limited applicability of the described tests, and special precautions should be taken against irreversible demagnetization.

IEC 60034-11:2020 is available as IEC 60034-11:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60034-11:2020 specifies requirements relating to the use of thermal protectors and thermal detectors incorporated into the stator windings or placed in other suitable positions in induction machines in order to protect them against serious damage due to thermal overloads. It applies to single-speed three-phase 50 Hz or 60 Hz cage induction motors in accordance with IEC 60034-1 and IEC 60034-12 that: - have a rated voltage up to 1 000 V; - are intended for direct-on-line or star-delta starting. The main changes with respect to the previous edition are: - the additional specification of winding temperature limits for temperature class 200 (N), - the increased limits of maximum winding temperatures for overloads with rapid variation, - the clarification that the motor winding may be permanently damaged after it has been exposed to temperatures - a clarification of the definition of indirect thermal protection, - a clarification on the test methods for larger motors.

This document applies to test methods for the measurement of the operational characteristics of brushes designed to operate on commutating and slip ring machines under specified test conditions. By extension some tests may be relevant for other kinds of sliding electrical contacts for electrical appliances.

IEC 60034-3:2020 applies to large three-phase synchronous generators, having rated outputs of 10 MVA and above driven by steam turbines or combustion gas turbines. Also included are synchronous Mvar compensators of the same output range connected to a grid for the purpose of exchanging reactive power. This document supplements basic requirements for rotating machines given in IEC 60034-1. This seventh edition cancels and replaces the sixth edition published in 2007. This edition includes the following significant technical changes with respect to the previous edition: - title modified; - scope extended to synchronous compensators; - rotor overcurrent requirements added; - impact of stator harmonics on rotor unbalanced load capability introduced; - synchronisation requirements added; - adjustments of temperatures or temperature rise revised for gas turbine applications; - requirements for auxiliaries updated.

IEC 60034-5:2020 is available as IEC 60034-5:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60034-5:2020 applies to the classification of degrees of protection provided by enclosures for rotating electrical machines. It defines the requirements for protective enclosures that are in all other respects suitable for their intended use and which, from the point of view of materials and workmanship, ensure that the properties dealt with in this document are maintained under normal conditions of use. This document does not specify degrees of protection against mechanical damage of the machine, or conditions such as moisture (produced for example by condensation), corrosive dust and vapour, fungus or vermin. This document is also applicable to explosion proof machines, but it does not specify the types of protection for use in a potentially explosive (dust, gas) environment. Those are defined in the IEC 60079 series of standards. This document gives definitions for standard degrees of protection provided by enclosures applicable to rotating electrical machines as regards the: a. protection of persons against contacts with or approach to live parts and against contact with moving parts (other than smooth rotating shafts and the like) inside the enclosure and protection of the machine against ingress of solid foreign objects b. protection of machines against the harmful effects due to ingress of water; c. protection of machines against the harmful effects due to ingress of dust. This fifth edition cancels and replaces the fourth edition, published in 2000, and its Amendment 1:2006.The main technical changes with respect to the previous edition are: - the inclusion of an additional second numeral 9 including its test method, - an additional note for clarification in Table 3, - a clarification on the term open drain hole, - a clarification on the ingress of dust in Table 4, - pressure values given now in Pa only, - a clarification in the scope on the applicability of this standard for (Ex) motors, - a new Clause 3 with definitions,

NEW!IEC 60034-12:2016 is available as IEC 60034-12:2016 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60034-12:2016 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 and explosion protection. The main changes with respect to the previous edition are as follows: - new design letter E for extended efficiency motors, explanation of all design letters, and description of new designs NE, NEY, HE, and HEY; - addition of a reference to IEC 60079-7; - addition of a formula to calculate locked rotor current from apparent power.

IEC 60034-2-3:2020 specifies test methods and an interpolation procedure for determining losses and efficiencies of converter-fed motors within the scope of IEC 60034-1:2017. The motor is then part of a variable frequency power drive system (PDS) as defined in IEC 61800‑9‑2:2017. Applying the approach of the comparable converter, the motor efficiency determined by use of this document is applicable for comparison of different motor designs only. The document also specifies procedures to determine motor losses at any load point (torque, speed) within the base speed range (constant torque range, constant flux range) based on determination of losses at seven standardized load points. This procedure is applicable to any variable speed AC motor (induction and synchronous) rated according to IEC 60034-1:2017 for operation on a variable frequency and variable voltage power supply.

IEC/TS 60034-18-42:2008 defines criteria for assessing the insulation system of stator/rotor windings of single or polyphase AC machines which are subjected to repetitive impulse voltages, such as pulse width modulation converters, and expected to withstand partial discharge activity during service. It specifies electrical qualification and acceptance tests on representative samples which verify fitness for operation with voltage-source converters.

IEC 60034-27-3:2015 provides guidelines for the test procedures and the interpretation of test results for dielectric dissipation factor measurements on the stator winding insulation of rotating electrical machines. These guidelines are valid for rotating electrical machines with conductive slot coatings operating at a rated voltage of 6 kV and higher. This standard applies to individual form-wound stator bars and coils outside a core (uninstalled), individual stator bars and coils installed in a core and complete form-wound stator winding of machines in new or aged condition. This edition includes the following significant technical changes with respect to the previous publication IEC TR 60894:1987: - inclusion of digital measurement of dissipation factor and capacitance; - inclusion of limits for dissipation factor values; - detailed description of measuring techniques; extension of scope to complete windings.

IEC 60034-19:2014 applies to d.c. machines rated 1 kW and above operating on rectifier-fed power supplies, d.c. buses or other d.c. sources and provides standardized methods intended to determine characteristic quantities for conventional and rectifier-fed d.c. machines. These methods supplement the requirements in IEC 60034-1 and IEC 60034-2-1. The main changes with regard to the previous edition are as follows: - description of the procedure for black band testing has been detailed and clarified; - procedures for measurement of the magnetization curves under no-load and load conditions have been added.

IEC 60034-2-1:2014(B) is intended to establish methods of determining efficiencies from tests, and also to specify methods of obtaining specific losses. This standard applies to d.c. machines and to a.c. synchronous and induction machines of all sizes within the scope of IEC 60034-1. This new edition includes the following significant technical changes with respect to the previous edition: grouping of the test methods into preferred methods and methods for field or routine testing; addition of the details of the requirements regarding instrumentation; addition of the description of tests required for a specific method in the same sequence as requested for the performance of the test.

2014-04-03: Publication allocated to tnaqvi@cencenelec.eu

IEC 60034-30-1:2014 specifies efficiency classes for single-speed electric motors that are rated according to IEC 60034-1 or IEC 60079-0, for operation on a sinusoidal voltage supply. This standard establishes a set of limit efficiency values based on frequency, number of poles and motor power. No distinction is made between motor technologies, supply voltage or motors with increased insulation designed specifically for converter operation even though these motor technologies may not all be capable of reaching the higher efficiency classes. This makes different motor technologies fully comparable with respect to their energy efficiency potential.

Defines criteria for assessing the insulation system of stator/rotor windings which are subjected to pulse width modulation drives. Applies to stator/rotor windings of single or polyphase AC machines with insulation systems for converter operation. Describes qualification and type tests on representative samples or on complete machines which verify fitness for operation with voltage source converters.

IEC 60034-28:2012 applies to three-phase low-voltage cage induction motors of frame numbers 56 to 400 as specified in IEC 60072-1. This standard establishes procedures to obtain values for elements of single phase equivalent circuit diagrams from tests and defines standard elements of these diagrams. This edition includes the following significant technical changes with respect to the previous edition: - the formulae are now all given for equivalent star-connection equivalent circuit diagrams; - procedures for the determination of equivalent circuit parameters from a load curve test as an alternative to the reverse rotation and locked rotor tests have been added.

IEC 60034-18-21:2012 gives test procedures for the thermal evaluation and classification of insulation systems used or proposed for use in wire-wound alternating current (a.c.) or direct current (d.c.) rotating electrical machines. The test performance of a candidate insulation system is compared to the test performance of a reference insulation system with proven service experience. The main technical changes with regard to the previous edition can be seen in the introduction of some basic statistical methods in the evaluation of comparative data. Moreover, the standard states a simpler use of different test procedures.

IEC 60034-18-31:2012 describes thermal endurance test procedures for classification of insulation systems used in a.c. or d.c. rotating electrical machines with indirect cooling and form-wound windings. These test procedures are intended to compare the thermal endurance performance of the mainwall insulation between conductor(s) and ground and, where required by the design of the coil or bar, the insulation between the turns. The main technical changes with regard to the previous edition include: - Definition of the test method and sub-cycles required to establish a consistent standardized platform for thermal ageing of insulation systems for form-wound windings. - Recommendations for establishing a thermal life curve based on confidence intervals. - Comparison of candidate and reference system performance for specific requirements of thermal class, within feasible limits. Keywords: rotating machinery, insulation systems

Deals with thermal cycling evaluation of insulation systems for form-wound windings. This kind of endurance is of special importance for long rotating machines ( especially indirectly cooled ) and machines that are exposed to a very large number of considerable load changes during normal operation.

IEC 60034-16-1:2011 defines terms applicable to the excitation systems of synchronous rotating electrical machines. The main technical changes with respect to the previous edition are some definitions which were added and some others which were brought up-to-date.

This publication has the status of a technical report - type 2.

IEC 60034-1:2010 is applicable to all rotating electrical machines except those covered by other IEC standards, for example, IEC 60349. Machines within the scope of this standard may also be subject to superseding, modifying or additional requirements in other publications, for example, IEC 60079 and IEC 60092. The changes with respect to the previous edition are as follows: - clarification of water coolant temperature, - recognition of IE code, - clarification of the term "tolerances".

IEC 60034-2-2:2010 applies to large rotating electrical machines and establishes additional methods of determining separate losses and to define an efficiency supplementing IEC 60034-2-1. These methods apply when full-load testing is not practical and result in a greater uncertainty.

IEC 60034-18-1:2010 deals with the general guidelines for functional evaluation of electrical insulation systems, used or proposed to be used in rotating electrical machines within the scope of IEC 60034-1, in order to qualify them. The main changes of this new edition with respect to the previous one are as follows: - provides general guidelines for functional evaluation of different types of windings as before but beyond that for electrical evaluation of windings which are electrically stressed by converter-supply; - is now focused on general guidelines with all technical details of procedures and qualification principles moved to the subsequent parts; - details additional general aspects of functional evaluation, particularly the statistical procedure for comparison between reference and candidate insulation systems and the evaluation of minor component or manufacturing changes; - contains a new acceptance test for verifying the expected production quality level of the insulation systems; - restricts the classification of insulation systems as a result of the functional evaluation to thermal classification.

IEC 60034-22:2009 establishes the principal characteristics of a.c. generators under the control of their voltage regulators when used for reciprocating internal combustion engine driven generating set applications and supplements the requirements given in IEC 60034-1. It covers the use of such generators for land and marine use, but excludes generating sets used on aircraft or used to propel land vehicles and locomotives. The most important changes with respect to the previous edition are: - technical changes to many definitions; - revision of table 1 and of the annex.

IEC 60034-15:2009 relates to a.c. machines incorporating form-wound stator coils and specifies the test procedures and voltages to be applied to the main and interturn insulation of sample coils. The changes of this new edition with respect to the previous one are as follows: - clarification of the title, - removal of the limitation on voltage, - additional definitions, - additional guidance.

IEC 60034-29 provides various indirect load tests, the purpose of which is to determine the temperature rise of rotating electrical machines, including a.c. induction machines, a.c. synchronous machines and d.c. machines. The test methods in some cases provide, in addition, means of measuring or estimating other parameters such as losses and vibration. Applies to machines covered by IEC 60034-1 when they cannot be loaded to a specific condition. Is applicable to both motors and generators.

IEC/TS 60034-18-33:2010 describes procedures for evaluation of insulation systems by endurance testing where thermal and electrical stresses are applied simultaneously. The procedures are intended for insulation systems used in a.c. electrical machines using form-wound windings. The test procedures provide a comparison of performance between reference and candidate systems at combinations of voltage and temperature which have been used separately to assess quality in the past and which are chosen to produce failures within a suitable timescale and at stresses within practical limits. The outcome of the test on the candidate insulation system will indicate whether it is better or worse than the reference system with proven service experience. The main changes of this new edition with respect to the previous one are as follows: - the requirement to investigate the nature of interactions between thermal and electrical stresses has been abandoned; - the use of single stress acceleration factors has been removed; - the selection of stress levels has been adjusted and the temperatures are now related to the thermal class temperature of the insulation system; - the introduction of end-point criteria; - a simplified method to display results.

IEC/TS 60034-24:2009 is applicable to the on-line detection and diagnosis of failures at the active parts of multi-phase rotating electrical machines (induction and synchronous machines) and of bearing currents. The failure analysis includes - inter-turn faults; - phase-to-phase short-circuits; - double earth faults and single earth faults of motors with earth connection of the star-point; - static and dynamic eccentricities; - cage imperfection or defects (e.g. broken bars or end-rings); - bearing currents.

Applies to a.c. and d.c. machines and specifies rules for the identification of winding connection points; marking of winding terminals; direction of rotation; relationship between terminal markings and direction of rotation; terminal marking of auxiliary devices; connection diagrams of machines for common applications. The main change with respect to the previous edition consists of changed terminal markings for d.c. machines.