Rotating electrical machines - Part 2-2: Specific methods for determining separate losses of large machines from tests - Supplement to IEC 60034-2-1 (IEC 60034-2-2:2010)

This part of IEC 60034 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. The specific methods described are: - Calibrated-machine method. - Retardation method. - Calorimetric method.

Drehende elektrische Maschinen - Teil 2-2: Besondere Verfahren zur Bestimmung der Einzelverluste großer elektrischer Maschinen aus Prüfungen - Ergänzung zu IEC 60034-2-1 (IEC 60034-2-2:2010)

Machines électrique tournantes - Partie 2-2: Méthodes spécifiques pour déterminer les pertes séparées des machines de grande taille - complément à la Partie 2-1 (CEI 60034-2-2:2010)

La CEI 60034-2-2:2010 s'applique à des machines électriques tournantes de grande taille et elle établit des méthodes supplémentaires pour la détermination des pertes séparées et qui sont destinées à définir un rendement, en complément de la CEI 60034-2-1. Ces méthodes s'appliquent lorsqu'un essai à pleine charge n'est pas possible ou qu'il présente une plus grande incertitude.

Električni rotacijski stroji - 2-2. del: Specifične metode za ugotavljanje posameznih izgub velikih strojev s preskušanjem - Dodatek k IEC 60034-2-1 (IEC 60034-2-2:2010)

Ta dokument vzpostavlja dodatne metode za ugotavljanje posameznih izgub ter opredelitev učinkovitosti, ki dopolnjujejo IEC 60034-2-1. Te metode veljajo, kadar preskušanje s polno obremenitvijo ni praktično in vodi do večje nezanesljivosti. Specifične opisane metode so: - Metoda s kalibracijo stroja. - Metoda z zakasnitvijo. - Kalorimetrična metoda.

General Information

Status
Published
Publication Date
12-Jul-2010
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
28-Jun-2010
Due Date
02-Sep-2010
Completion Date
13-Jul-2010

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Drehende elektrische Maschinen - Teil 2-2: Besondere Verfahren zur Bestimmung der Einzelverluste großer elektrischer Maschinen aus Prüfungen - Ergänzung zu IEC 60034-2-1 (IEC 60034-2-2:2010)Machines électrique tournantes - Partie 2-2: Méthodes spécifiques pour déterminer les pertes séparées des machines de grande taille - complément à la Partie 2-1 (CEI 60034-2-2:2010)Rotating electrical machines - Part 2-2: Specific methods for determining separate losses of large machines from tests - Supplement to IEC 60034-2-1 (IEC 60034-2-2:2010)29.160.01Rotacijski stroji na splošnoRotating machinery in generalICS:Ta slovenski standard je istoveten z:EN 60034-2-2:2010SIST EN 60034-2-2:2010en,fr01-september-2010SIST EN 60034-2-2:2010SLOVENSKI
STANDARD



SIST EN 60034-2-2:2010



EUROPEAN STANDARD EN 60034-2-2 NORME EUROPÉENNE
EUROPÄISCHE NORM June 2010
CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Management Centre: Avenue Marnix 17, B - 1000 Brussels
© 2010 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60034-2-2:2010 E
ICS 29.160
English version
Rotating electrical machines -
Part 2-2: Specific methods for determining separate losses of large machines from tests -
Supplement to IEC 60034-2-1 (IEC 60034-2-2:2010)
Machines électrique tournantes -
Partie 2-2: Méthodes spécifiques
pour déterminer les pertes séparées
des machines de grande taille
à partir d'essais -
Complément à la CEI 60034-2-1 (CEI 60034-2-2:2010)
Drehende elektrische Maschinen -
Teil 2-2: Besondere Verfahren
zur Bestimmung der Einzelverluste großer elektrischer Maschinen aus Prüfungen -
Ergänzung zu IEC 60034-2-1 (IEC 60034-2-2:2010)
This European Standard was approved by CENELEC on 2010-06-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
SIST EN 60034-2-2:2010



EN 60034-2-2:2010 - 2 - Foreword The text of document 2/1585/FDIS, future edition 1 of IEC 60034-2-2, prepared by IEC TC 2, Rotating machinery, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60034-2-2 on 2010-06-01. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent rights. The following dates were fixed: – latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement
(dop)
2011-03-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2013-06-01 Annex ZA has been added by CENELEC. __________ Endorsement notice The text of the International Standard IEC 60034-2-2:2010 was approved by CENELEC as a European Standard without any modification. __________ SIST EN 60034-2-2:2010



- 3 - EN 60034-2-2:2010 Annex ZA
(normative)
Normative references to international publications with their corresponding European publications
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.
NOTE
When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.
Publication Year Title EN/HD Year
IEC 60034-1 - Rotating electrical machines -
Part 1: Rating and performance EN 60034-1 -
IEC 60034-2-1 - Rotating electrical machines -
Part 2-1: Standard methods for determining losses and efficiency from tests (excluding machines for traction vehicles) EN 60034-2-1 -
SIST EN 60034-2-2:2010



SIST EN 60034-2-2:2010



IEC 60034-2-2Edition 1.0 2010-03INTERNATIONAL STANDARD NORME INTERNATIONALERotating electrical machines –
Part 2-2: Specific methods for determining separate losses of large machines from tests – Supplement to IEC 60034-2-1
Machines électriques tournantes –
Partie 2-2: Méthodes spécifiques pour déterminer les pertes séparées des machines de grande taille à partir d’essais – Complément à la CEI 60034-2-1
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE UICS 29.160 PRICE CODECODE PRIXISBN 2-8318-1083-4
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale ® SIST EN 60034-2-2:2010



– 2 – 60034-2-2 © IEC:2010 CONTENTS FOREWORD.3 1 Scope.5 2 Normative references.5 3 Terms and definitions.5 4 Symbols.6 4.1 Quantities.6 4.2 Subscripts.6 5 Basic requirements.7 5.1 Direct and indirect efficiency determination.7 5.1.1 Direct.7 5.1.2 Indirect.7 5.2 Uncertainty.7 5.3 Preferred methods.7 6 Common determinations.8 6.1 Efficiency.8 6.2 Total loss.8 6.3 Load losses.9 7 Methods.9 7.1 Calibrated machine method.10 7.1.1 General.10 7.1.2 Machine calibration.10 7.1.3 Test procedure.10 7.1.4 Determination of performance.11 7.2 Retardation method.12 7.2.1 Fundamentals.12 7.2.2 Test procedure.12 7.2.3 Determination of deceleration.14 7.2.4 Determination of retardation constant.15 7.2.5 Determination of losses.16 7.3 Calorimetric method.17 7.3.1 General.17 7.3.2 Calorimetric instrumentation.19 7.3.3 Test procedure.22 7.3.4 Determination of losses.22
Figure 1 – Method of the chord.15 Figure 2 – Reference surface.18 Figure 3 – Four coolers connected in parallel, single calorimeter, single coolant.20 Figure 4 – Series connected coolers, two coolants.20 Figure 5 – Bypass piping.21 Figure 6 – Parallel piping.21 Figure 7 – Characteristics of pure water as a function of temperature.23
Table 1 – Preferred methods for large machines.8
SIST EN 60034-2-2:2010



60034-2-2 © IEC:2010 – 3 – INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
ROTATING ELECTRICAL MACHINES –
Part 2-2: Specific methods for determining
separate losses of large machines from tests –
Supplement to IEC 60034-2-1
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. International Standard IEC 60034-2-2 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 2/1585/FDIS 2/1595/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. SIST EN 60034-2-2:2010



– 4 – 60034-2-2 © IEC:2010 NOTE A table of cross-references of all IEC TC 2 publications can be found in the IEC TC 2 dashboard on the IEC website. The committee has decided that the contents of this amendment and the base publication will remain unchanged until the stability 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.
SIST EN 60034-2-2:2010



60034-2-2 © IEC:2010 – 5 – ROTATING ELECTRICAL MACHINES –
Part 2-2: Specific methods for determining
separate losses of large machines from tests –
Supplement to IEC 60034-2-1
1 Scope This part of IEC 60034 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. NOTE In situ testing according to the calorimetric method for full-load conditions is recognized. The specific methods described are: – Calibrated-machine method. – Retardation method. – Calorimetric method. 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)
3 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 60034-1 and IEC 60034-2-1 apply, as well as the following. 3.1
calibrated machine
machine whose mechanical power input/output is determined, with low uncertainty, using measured electrical output/input values according to a defined test procedure 3.2
calibrated-machine method method in which the mechanical input/output to/from an electrical machine under test is determined from the measurement of the electrical input/output of a calibrated machine mechanically coupled to the test machine
3.3
retardation method method in which the separate losses in a machine under test are deduced from the measurements of the deceleration rate of its rotating components when only these losses are present SIST EN 60034-2-2:2010



– 6 – 60034-2-2 © IEC:2010 3.4
calorimetric method method in which the losses in a machine are deduced from the measurements of the heat generated by them 3.5
thermal equilibrium the state reached when the temperature rises of the several parts of the machine do not vary by more than a gradient of 2 K per hour [IEV 411-51-08] 4 Symbols
In addition to the symbols in IEC 60034-2-1, the following apply.
4.1 Quantities A
is an area, m2, C is the retardation constant, kg m2 min2,
cp
is the specific heat capacity of the cooling medium, J/(kg K), h
is the coefficient of heat transfer, W/(m2 K), J is the moment of inertia, kg m2, n is the speed, min–1, P1E is the excitation power supplied by a separate source, W, Pk is the constant loss, W, Pel
is the electrical power, excluding excitation, W, Pe
is the excitation power, W, PFe is the iron loss, W, Pfw is the friction and windage loss, W, Psc is the short-circuit loss, W, Pmech is the mechanical power, W, PT is the total loss, W, Q
is the volume rate of flow of the cooling medium, m3/s, t is the time, s, v
is the exit velocity of cooling medium, m/s, Δp
is the difference between the static pressure in the intake nozzle and ambient pressure, N/m2, Δ
is the temperature rise of the cooling medium, or the temperature difference between the machine reference surface and the external ambient temperature, K, / is the per unit deviation of rotational speed from rated speed, ρ is the density of the cooling medium, kg/m3,
is the temperature, °C. 4.2 Subscripts irs for inside reference surface, ers
for outside reference surface, E for exciter, c for the cooling circuit, SIST EN 60034-2-2:2010



60034-2-2 © IEC:2010 – 7 – N for rated values, rs
for the reference surface,
t for a test procedure, 1 for input or initial condition, 2
for output condition. 5 Basic requirements 5.1 Direct and indirect efficiency determination Tests can be grouped in the following categories. 5.1.1 Direct Input-output measurements on a single machine are considered to be direct. This involves the measurement of electrical or mechanical power into, and mechanical or electrical power out of a machine. 5.1.2 Indirect Measurements of the separate losses in a machine under a particular condition are considered to be indirect. This is not usually the total loss but comprises certain loss components. The method may, however, be used to calculate the total loss or to calculate a loss component. The determination of total loss shall be carried out by one of the following methods: – direct measurement of total loss; – summation of separate losses. NOTE The methods for determining the efficiency of machines are based on a number of assumptions. Therefore, it is not possible to make a comparison between the values of efficiency obtained by different methods. 5.2 Uncertainty Uncertainty as used in this standard is the uncertainty of determining a true efficiency. It reflects variations in the test procedure and the test equipment. Although uncertainty should be expressed as a numerical value, such a requirement needs sufficient testing to determine representative and comparative values. This standard uses the following relative uncertainty terms: – "low" applies to efficiency determinations based solely upon test results; – "medium" applies to efficiency determinations based upon limited approximations; – "high" applies to efficiency determinations based upon assumptions. 5.3 Preferred methods It is difficult to establish specific rules for the determination of efficiency. The choice of test to be made depends on the information required, the accuracy required, the type and size of the machine involved and the available field test equipment (supply, load or driving machine). Preferred methods for large machines are given in Table 1. SIST EN 60034-2-2:2010



– 8 – 60034-2-2 © IEC:2010 Table 1 – Preferred methods for large machines Quantity to be determined Test method Clause Uncertainty Direct efficiency Calibrated machine
7.1.4.1 medium Total losses Calorimetric 1
7.3.3d) low/medium Calibrated machine
7.1.4.2a) medium Retardation
7.2.5.2 medium Friction and windage loss Calorimetric
7.3.3a) low/medium Calibrated machine
7.1.4.2b) medium Retardation
7.2.5.3 medium Active iron loss, and additional open-circuit losses in d.c. and synchronous machines Calorimetric
7.3.3b) low/medium Calibrated machine
7.1.4.2c) medium Retardation
7.2.5.5 medium Winding and additional-load losses Calorimetric
7.3.3c) low/medium
6 Common determinations These determinations are applicable to more than one of the listed methods. 6.1 Efficiency Efficiency is: T221E1TE11PPPPPPPP+=+−+=η where P1
is the input power excluding excitation power from a separate source; P2
is the output power; P1E
is the excitation power supplied by a separate source; PT
is the total loss according to 6.2. NOTE 1 Input power P1 and output power P2 are as follows: in motor operation: P1 = Pel; P2 = Pmech; in generator operation: P1 = Pmech; P2 = Pel. NOTE 2 PT includes the excitation power Pe of the machine where applicable. 6.2 Total loss When the total loss is determined as the sum of the separate losses the following formulae apply: For direct current machines: PT = Pk + Pa + Pb + PLL + Pe ___________ 1
If the relative error in Pirs (see
7.3.1) is likely to be greater than 3 %, the calorimetric method is not recommended. SIST EN 60034-2-2:2010



60034-2-2 © IEC:2010 – 9 – Pe = Pf + PE Pk = Pfw + PFe For induction machines: PT = Pk + Ps + Pr + PLL Pk = Pfw + PFe For synchronous machines: PT = Pk + Pa + PLL + Pe Pe = Pf + PE+ Pb Pk = Pfw + PFe where: Pa is the I2R armature-winding loss (interpole, compensation and series field winding loss in case of d.c. machines), Pb is the brush loss, PE is the exciter loss, Pe is the excitation power, Pf is the excitation (field winding) loss, PFe is the iron loss, Pfw is the friction and windage loss, Pk is the constant loss, PLL is the additional load loss, Pr is the I2R rotor winding loss, Ps is the stator I2R winding loss, PT is the total loss. 6.3 Load losses Losses relative to machine load (with lowest uncertainty) are best determined from actual measurements. For example: measurements of current, resistance, etc. under full-load operation. When this is not possible, these values shall be obtained from calculation of the parameters during the design stage. Determination of losses not itemized in this part may be found in IEC 60034-2-1. 7 Methods For the determination of performance when machine load and/or size exceed test capabilities (described in IEC 60034-2-1), the following test methods may be used.
NOTE These methods are generally applicable to large machines where the facility cost for other methods is not economical. SIST EN 60034-2-2:2010



– 10 – 60034-2-2 © IEC:2010 7.1 Calibrated machine method The calibrated machine method may be used to determine the test machine efficiency either directly or by separate losses. 7.1.1 General This method is generally applied as a factory test. This method requires a calibrated machine mechanically coupled to the machine under test and is used when neither a torque meter nor dynamometer is available. The mechanical input of the tested machine is calculated from the electrical input of the calibrated machine. 7.1.2 Machine calibration When a gear-box is directly connected to the machine it shall be considered as part of the calibrated machine. Calibrate an electric machine, preferably a direct-current machine, according to one of the procedures in IEC 60034-2-1 at a sufficient number of thermally stable loads (including no-load) to determine an accurate relationship of output power as a function of input power adjusted for the temperature of the cooling air/medium at inlet. This is generally developed in the form of a curve. NOTE It is generally advisable to take several readings of all instruments at each load-point during short periods of time and average the results to obtain a more accurate test value. 7.1.3 Test procedure The tested machine shall be equipped with winding ETDs. The tested machine shall be completely assembled with essential components as for normal operation. Before starting the test, record the winding resistances and the ambient temperature. The machine for which the performance is to be determined shall be mechanically coupled to the calibrated machine and be operated at a speed equivalent to its synchronous/rated speed. Operate the calibrated machine with the test machine at either rated-load, partial-load; no-load not excited, with or without brushes; no-load excited at rated voltage; or short-circuited, which enables specific categories of losses to be determined. When the test machine is operated at each specified test condition and has reached thermal stability, record: NOTE The following example represents testing with a motor as the calibrated machine. – for the calibrated machine P1 = power U1 = input voltage I1 = current
1c
= temperature of inlet cooling air
1w
= winding temperature (by variation of resistance if possible) n1 = speed – for the test machine (direct determination as a generator) P2 = output power SIST EN 60034-2-2:2010



60034-2-2 © IEC:2010 – 11 – U2 = output voltage I2 = armature load current
2w = windings temperature (either directly by ETDs or by resistance variation) n2 = speed – for the unloaded test machine (as a generator) U2 = armature voltage (when excited open-circuit) I2 = armature current (when excited short-circuit)
2w = windings temperature (either directly by ETDs or by resistance variation) n2 = speed Upon completion of each test, stop the machines and record in the given order: – test machine winding resistance; – calibrated machine winding resistance. Finally operate the calibrated machine without electrical connection to the test machine and record as specified above. 7.1.4 Determination of performance From the curve developed in
7.1.2 and using the calibrated machine input values, select the appropriate output power to the test machine. Adjust the output power for the standardized coolant temperature. Determination of excitation power shall be in accordance with IEC 60034-2-1. 7.1.4.1 Direct efficiency determination When tested according to
7.1.3 the test machine efficiency is: 12PP=η test machine working as a generator, calibrated machine working as a motor where P2 is the output power of test generator P1
is the calculated input power to the test generator according to
7.1.3. and: 12PP=η test machine working as a motor, calibrated machine working as a generator where P1
is the input power to test motor P2
is the calculated output power from the test motor. 7.1.4.2 Separate losses Using values of P determined from the calibrated machine curve, it is possible to determine the power dissipated by the test machine for other selected conditions that may be used to determine efficiency according to 6.1. SIST EN 60034-2-2:2010



– 12 – 60034-2-2 © IEC:2010 a) Friction and windage loss at rated speed (when the test machine is not electrically connected); b) Active iron loss, and additional open-circuit losses in d.c. and synchronous machines, (when tested at no-load, open-circuit, excited at rated voltage, minus the windage and friction loss). Field losses from a separate source; c) Armature-winding loss and additional-load loss in synchronous machines, (when tested under short-circuit conditions, excited at rated armature current, minus the windage and friction loss). Field losses from a separate source. 7.2 Retardation method The retardation method can be used in determining the separate losses of rotating electrical machines having an appreciable rotational inertia. The retardation method is used to determine: – sum of the friction loss and windage loss ("mechanical losses") in machines of all types; – sum of losses in active iron and additional open-circuit losses in d.c. and synchronous machines; – sum of I2R losses in an operating winding and additional-load losses ("short-circuit losses") in synchronous machines. 7.2.1 Fundamentals The recorded test loss Pt which retards the machine is proportional to the product of the speed at which this loss corresponds and the deceleration at that speed: dtdnCnP−=t where: Pt
is the loss being measured, W; C
is the retardation constant according to
7.2.4; n
is the speed, min–1; dn/dt
is the deceleration from
7.2.3. NOTE The accuracy of the retardation method is directly related to the accuracy of the retardation constant C which depends solely on the moment of inertia J (see
7.2.4). 7.2.2 Test procedure 7.2.2.1 Assembly of test machine The test machine shall be assembled, with all essential components, as for normal operation, but uncoupled from other rotating parts. A suitable speed sensor shall be attached to the rotating element. NOTE When the machine cannot be uncoupled, all possible steps should be
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