IEC 60909 0 2001 Short Circuit Current_Resumen

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Short-circuit currents in three-phase

a.c. systems –

Part 0:

Calculation of currents

Reference number Reference number IEC 60909-0:2001(E) IEC 60909-0:2001(E)

INTERNATIONAL

STANDARD

IE

IEC

C

60909-0

First edition First edition 2001-07 2001-07

This

This English-language

English-language version is derived from the original

version is derived from the original

bilingual

publication by leaving out all French-language

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Short-circuit currents in three-phase

a.c. systems –

Part 0:

Calculation of currents

For price, see current catalogue For price, see current catalogue

©

No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopy

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Internationa

International Electrotechnical Electrotechnical Commission, l Commission, 3, rue de Varembé, PO Box 131, CH-1211 Genev3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerlanda 20, Switzerland Telephone:

Telephone: +41 +41 22 22 919 919 02 02 11 11 Telefax: Telefax: +41 +41 22 22 919 919 03 03 00 00 E-mail: E-mail: [email protected] [email protected] Web: Web: www.iec.chwww.iec.ch

STANDARD

60909-0

First edition First edition 2001-07 2001-07

XB

Commission Electrotechnique Internationale Commission Electrotechnique Internationale Internati

International onal ElectrotechnicElectrotechnical al CommissionCommission Международная

Международная ЭлектротехническаяЭлектротехническая КомиссияКомиссия

PRICE CODE PRICE CODE

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60909-0 60909-0 ©©_I_IE_EC_C::2₂₀₀₀₀₁₁ _–_– ₃₃ _–_– CONTENTS CONTENTS FOREWORD... FOREWORD... 99 1

1 GeneGeneralral ... 1313 1.1

1.1 ScopScopee ... 1313 1.2

1.2 NormNormativative e refereferencrenceses ... 1515 1.3

1.3 DefiDefinitionitionsns ... 1717 1.4

1.4 SymSymbols, subsbols, subscriptcripts and superss and superscriptcripts...s... 2525 1.4.1

1.4.1 SymSymbolsbols ... 2525 1.4.2

1.4.2 SubsSubscriptcriptss ... 2929 1.4.3

1.4.3 SupeSuperscrrscriptsipts ... 3131 2

2 CharCharacteacteristiristics of shocs of short-crt-circuiircuit curret currents: cants: calculalculating mting methodethod... 3131 2.1

2.1 GeneGeneral..ral... 3131 2.2

2.2 CalcCalculatulation ion assassumpumptions...tions... 3535 2.3

2.3 MethMethod of cod of calcualculatiolationn ... 3535 2.3.1

2.3.1 EquivEquivalenalent vt voltagoltage e sourcsource ae at tht the se short-hort-circcircuit uit localocationtion ... 3535 2.3.2

2.3.2 AppliApplicatication on of of symsymmetmetricarical l comcomponeponentsnts ... 4141 2.4

2.4 MaxiMaximum mum shortshort-ci-circuit rcuit currcurrentsents ... 4545 2.5

2.5 MinimMinimum shorum short-ct-circuiircuit currentt currentss ... 4747 3

3 ShortShort-ci-circuit imrcuit impedapedances of elecnces of electricatrical equipml equipment...ent... 4747 3.1

3.2 NetwNetwork ork feedfeedersers ... 4949 3.3

3.3 TranTransforsformermerss ... 5151 3.3.1

3.3.1 Two-Two-windiwinding trang transfornsformermerss ... 5151 3.3.2

3.3.2 ThreThree-we-windininding transg transformformersers ... 5353 3.3.3

3.3.3 ImImpedapedance nce corrcorrectioection fan factors ctors for for two- two- and and threethree-win-windingding network

network transformtransformersers ... 5757 3.4

3.4 OveOverhearhead lines and lines and cabled cabless ... 5959 3.5

3.5 ShorShort-cit-circuit rcuit limilimiting ting reacreactorstors ... 6161 3.6

3.6 SyncSynchronohronous us mamachinchineses ... 6161 3.6.1

3.6.1 SyncSynchronhronous gous geneeneratorratorss ... 6161 3.6.2

3.6.2 SyncSynchronohronous cus compompensaensators tors and and motmotorsors ... 6565 3.7

3.7 PowePower statir station uniton unit ... 6565 3.7.1

3.7.1 PowePower star station tion units units with with on-on-load load tap-tap-chanchanger...ger... 6565 3.7.2

3.7.2 PowePower sr station tation units units withowithout out on-lon-load ad tap-tap-chanchanger...ger... 6969 3.8

3.8 AsyAsynchrnchronous onous motmotors...ors... 7171 3.8.1

3.8.1 GeneGeneralral ... 7171 3.8.2

3.8.2 ContriContributiobution n to to shorshort-cit-circuit rcuit currcurrents ents by by asyasynchrnchronous onous motmotorsors ... 7373 3.9

3.9 StatStatic ic convconverteerters...rs... 7777 3.10

3.10 CapaCapacitorcitors s and and non-non-rotatrotating ing loadloadss ... 7777 4

4 CalcCalculatiulation of on of shortshort-ci-circuit rcuit currcurrentsents ... 7979 4.1

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4.2.1

4.2.1 ThreThree-pe-phase shorhase short t circcircuit....uit... 8383 4.2.2

4.2.2 LineLine-to--to-line sline short chort circuiircuitt ... 9595 4.2.3

4.2.3 LineLine-to--to-line sline short chort circuiircuit with t with eartearth conh connectnection..ion... 9999 4.2.4

4.2.4 LineLine-to--to-eartearth h shorshort t circcircuituit ...101.101 4.

4.33 PePeak sak shohortrt--cicircrcuiuit cut currrrenentt ii p p...101...101

4.3.1

4.3.1 ThreThree-pe-phase hase shorshort t circcircuit....uit...10....1011 4.3.2

4.3.2 LineLine-to--to-line line short circuitshort circuit ...10...1055 4.3.3

4.3.3 LineLine-to--to-line shorline short circuit with eat circuit with earth connerth connectionction...10....1055 4.3.4

4.3.4 LineLine-to--to-eartearth h shorshort t circcircuituit ...107.107 4.4

4.4 DC comDC componeponent of the shornt of the short-ct-circuircuit curreit currentnt ...107...107 4.5

4.5 SySymmmmetretricaical shl shortort-c-circircuit uit brebreakaking ing curcurrenrentt I I b b...107...107

4.5.1

4.5.1 Far-Far-fromfrom-ge-generanerator tor short short circcircuituit ...107..107 4.5.2

4.5.2 NeaNear-to-r-to-gengeneraterator or short circuitshort circuit ...10....1099 4.

4.66 StSteaeadydy-s-statate shte shorort-t-cicircrcuit cuit cururrerentnt I I k k ...117...117

4.6.1

4.6.1 ThreeThree-ph-phase ase short short circcircuit ouit of one f one genegenerator rator or onor one powe power ser station tation unitunit ...117.117 4.6.2

4.6.2 ThreThree-pe-phase shhase short circort circuit in non-uit in non-mesmeshed nethed networkworks...s...12....1211 4.6.3

4.6.3 ThreThree-pe-phase shhase short circuort circuit in mesheit in meshed netword networks...ks...123...123 4.6.4

4.6.4 UnbaUnbalanclanced ed short short circcircuits...uits...123.123 4.6.5

4.6.5 ShorShort circt circuits auits at the lt the low-vow-voltagoltage side e side of traof transfornsformermers, if os, if one linne line cone conductoductor r is interrupted at the high-voltage side

is interrupted at the high-voltage side ...125.125 4.7

4.7 TermTerminal shorinal short circuit of asynct circuit of asynchronohronous motorus motors...s...1...12727 4.8

4.8 Joule inJoule integrtegral and thal and thermermal equial equivalevalent shortnt short-ci-circuit crcuit currenurrentt ...129..129 Annex

Annex A (normA (normative) ative) Equations Equations for the for the calculation calculation of the of the factorsfactors mm and and nn ...137...137 Figure 1 –

Figure 1 – Short-circuit current of a Short-circuit current of a far-fromfar-from-gener-generator short ator short circuit withcircuit with constant

constant a.c. a.c. componecomponent nt (schem(schematic atic diagramdiagram)...)...31...31 Figure 2 – Short-circuit current of a

Figure 2 – Short-circuit current of a near-to-near-to-generator short circuit withgenerator short circuit with decaying a.c.

decaying a.c. componecomponent nt (schem(schematic atic diagramdiagram)) ...33...33 Figure 3 –

Figure 3 – CharacterCharacterization of short ization of short circuits and their currents...circuits and their currents...37...37 Figure 4 –

Figure 4 – Illustration for calculating the Illustration for calculating the initial symmetricainitial symmetrical short-circuit currentl short-circuit current I I _k_k′′′′ in compliance with the procedure for the equivalent voltage sourc

in compliance with the procedure for the equivalent voltage sourcee ...39...39 Figure 5 – Short-circuit impedances of a three-phase a.c. system at

Figure 5 – Short-circuit impedances of a three-phase a.c. system at the

the short-circshort-circuit uit location location F...F...43...43 Figure 6 – System diagram and equiva

Figure 6 – System diagram and equivalent circuit diagram for network feederslent circuit diagram for network feeders ...49...49 Figure 7 –

Figure 7 – Three-wThree-winding transformer (examinding transformer (example)ple) ...55...55 Figure 8 – Phasor diagram

Figure 8 – Phasor diagram of a synchronous geneof a synchronous generator at rated conditionsrator at rated conditions ...63...63 Figure 9 – Example for the estimation of the

Figure 9 – Example for the estimation of the contribution from the asynchronous mcontribution from the asynchronous motorsotors in relation

in relation to to the total the total short-circshort-circuit uit current...current...75...75 Figure 10 – Diagram to determine the short-circuit type (figure 3) for the highest

Figure 10 – Diagram to determine the short-circuit type (figure 3) for the highest short-circuit current referred to

short-circuit current referred to the symmetricathe symmetrical three-phase short-circuit current atl three-phase short-circuit current at the short-circuit location when the

the short-circuit location when the impedancimpedance angles of e angles of the sequencethe sequence impedances

impedances Z Z (1)(1),, Z Z (2)(2),, Z Z (0)(0) are are identicalidentical ...81...81

Figure 11

Figure 11 – Examples of – Examples of single-fesingle-fed short d short circuits...circuits...85...85 Figure 12 –

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60909-0

60909-0 ©©_I_IE_EC_C::2₂₀₀₀₀₁₁ _–_– ₇₇ _–_–

Figure 13 –

Figure 13 – Short-circuit currents and partial short-circuit currents for Short-circuit currents and partial short-circuit currents for three-phasthree-phasee short circuits between generator and unit

short circuits between generator and unit transformetransformer with r with or without or without on-load tap-chaon-load tap-changer,nger, or at the

or at the connection to the auxiliary transformer of a power station unit and connection to the auxiliary transformer of a power station unit and at theat the auxiliary

auxiliary busbar busbar AA ...89...89 Figure 14 –

Figure 14 – Example of a Example of a meshemeshed network fed d network fed from several sources...from several sources...97...97 Figure 15 – Factor

Figure 15 – Factor κ κ for series circuit as a function of ratio for series circuit as a function of ratio R R// X X or or X X // R R ...101...101 Figure 16 – Factor

Figure 16 – Factor µ µ for for calculation of short-circuit breaking currentcalculation of short-circuit breaking current I I b b...111...111

Figure 17 – Factor

Figure 17 – Factor qq for for the calculation of the calculation of the symmetricthe symmetrical short-circuit breakingal short-circuit breaking current of

current of asynchroasynchronous motorsnous motors ...113...113 Figure 18 –

Figure 18 –λ λ minmin and and λ λ maxmax factors for cylindrical rotor generators factors for cylindrical rotor generators ...119...119

Figure 19 – Factors

Figure 19 – Factors λ λ minmin and and λ λ maxmax for salient-pole gene for salient-pole generatorsrators ...119...119

Figure 20 – Transformer secondary short circuits, if one line (fuse) is opened on Figure 20 – Transformer secondary short circuits, if one line (fuse) is opened on thethe high-vo

high-voltage side of ltage side of a transformer Dyn5a transformer Dyn5 ... 125125 Figure 21 – Factor

Figure 21 – Factor mm for the for the heat effect of the d.c. component of the short-circuit currentheat effect of the d.c. component of the short-circuit current (for programming, the equation for

(for programming, the equation for mm is is given in annex given in annex A)...A)...131...131 Figure 22 – Factor

Figure 22 – Factor nn for the for the heat effect of the a.c. component of the short-circuit currentheat effect of the a.c. component of the short-circuit current (for programming, the equation for

(for programming, the equation for nn is given in annex A is given in annex A)) ...133...133 Table 1 – Voltage factor

Table 1 – Voltage factor cc...41...41 Table 2 – Factors

Table 2 – Factors α α and and β β for the for the calculation of short-circuit currents with equation (90)calculation of short-circuit currents with equation (90) Rated transformation ratio

Rated transformation ratio t t r r = = U U rTHVrTHV//U U rTLVrTLV...127...127

Table 3 – Calculation of

Table 3 – Calculation of short-circuit currents of asynchshort-circuit currents of asynchronous motors in the case of ronous motors in the case of a short circuit at the terminals (se

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INTERNATIONAL ELECTROTECHNICAL COMMISSION INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________

SHORT-CIRCUIT CURRENTS IN THREE-PHASE AC SYSTEMS –

Part 0: Calculation of currents

FOREWORD FOREWORD

1)

1) The IEC (InternationaThe IEC (International Electrotechnical Electrotechnical Commissiol Commission) is a n) is a worldwworldwide organizaide organization for standardization for standardization comprisingtion comprising all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, the IEC publishes International Standards. Their preparation is this end and in addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may entrusted to technical committees; any IEC National Committee interested in the subject dealt with may part

participicipate ate in in this this prepapreparatoratory ry work. work. InteInternatrnationalional , , governgovernmental mental and and non-gonon-go vernmenvernmen tal tal organorganizatiizati ons ons liailiai singsing with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2)

2) The formaThe formal decisions or agreel decisions or agreements of the IEC on technicments of the IEC on technical matters exal matters express, as nearly apress, as nearly as possible, an internations possible, an internationalal consensus of opinion on the relevant subjects since each technical committee has representation from all consensus of opinion on the relevant subjects since each technical committee has representation from all interested National Committees.

interested National Committees. 3)

3) The documThe documents produceents produced have the form of recd have the form of recommommendations for interendations for international use and are published in the form of national use and are published in the form of standards, technical specifications, technical reports or guides and they are accepted by the National Committees standards, technical specifications, technical reports or guides and they are accepted by the National Committees in that sense.

in that sense.

4)

4) In order to promote international unification, IEC National Committees undertake to apply IEC InternationalIn order to promote international unification, IEC National Committees undertake to apply IEC International Standards transparently to the maximum extent possible in their national and regional standards. Any divergence Standards transparently to the maximum extent possible in their national and regional standards. Any divergence betwee

betwee n n the the IEC IEC StanStandard dard and and the the correcorrespondsponding ing natinati onal onal or or regioregional nal standstandard ard shalshall l be be clearclearly ly indiindi cated cated in in thethe latter.

latter.

5)

5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for anyThe IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with one of its standards.

equipment declared to be in conformity with one of its standards.

6)

6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of paten

paten t rit ri ghts. ghts. The IThe IEC sEC shall hall not not be hebe held rld r esponsespons ible ible for for identident ifyinifying any g any or aor all ll such such patenpatent rt rightights.s.

International Standard IEC 60909-0 has been prepared by IEC technical committee 73: International Standard IEC 60909-0 has been prepared by IEC technical committee 73: Short-circuit currents.

circuit currents.

This first edition cancels and replaces IEC 60909 published in 1988 and constitutes a technical This first edition cancels and replaces IEC 60909 published in 1988 and constitutes a technical revision.

revision. The text of

The text of this standard is based on this standard is based on the following documents:the following documents:

F

FDDIISS RReeppoorrt t oon n vvoottiinngg 7

733//111199//FFDDIISS 7733//112211//RRVVDD

Full information on the voting for the approval of this standard can be found in the report on Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table.

voting indicated in the above table. Annex A forms an integral part of

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60909-0

60909-0 ©©_I_IE_EC_C::2₂₀₀₀₀₁₁ _–_–₁₁₁₁ _–_–

This part of IEC 60909 shall be read in conjunction with the International Standards, Technical This part of IEC 60909 shall be read in conjunction with the International Standards, Technical Reports and

Reports and Technical Specifications mentioned below:Technical Specifications mentioned below: –

– IEC IEC TR TR 60909-1,—60909-1,— Short-circuit current calculation in three-phase a.c. systems – Part 1:Short-circuit current calculation in three-phase a.c. systems – Part 1: Factors

Factors for for the the calculacalculation tion of of short-cshort-circuit ircuit currents currents in in three-phthree-phase ase a.c. a.c. systems systems accordinaccording g to IEC 60909-0

to IEC 60909-01)1)

–

– IEC TIEC TR3 6R3 609090909-2:1-2:1992,992, Elec Electritrical cal equiequipmenpment – t – Data Data for for shorshort-cit-circuircuit ct curreurrent nt calccalculaulatiotions ns inin accordance with IEC 60909

accordance with IEC 60909 –

– IEC IEC 609060909-3:9-3:19951995,, Short-circuit current calculation in three-phase a.c. systems – Part 3:Short-circuit current calculation in three-phase a.c. systems – Part 3: Currents during two separate simultaneous single-phase line-to-earth short circuits and Currents during two separate simultaneous single-phase line-to-earth short circuits and part

part ial ial shorshort-ct-circuircuit it currcurrents ents folfollowlowing ing thrthrough ough eartearthh –

– IEC TIEC TR 60R 60909-4909-4:200:2000,0, Short-circuit current calculation in three-phase a.c. systems – Part 4:Short-circuit current calculation in three-phase a.c. systems – Part 4: Exam

Examples ples for for the the calcalculaculatiotion of n of shorshort-cit-circuircuit cut currenrrentsts

The committee has decided that the contents of this publication will remain unchanged until 2007. The committee has decided that the contents of this publication will remain unchanged until 2007. At this date, the publication will be

At this date, the publication will be •• rreeccoonnffiirrmmeedd;;

•• wwiitthhddrraawwnn;;

•• rereplplacaced ed by by a ra revevisised ed ededitiitionon, o, or r •• aammeennddeedd..

The contents of the corrigendum of February 2002 have been included in this copy. The contents of the corrigendum of February 2002 have been included in this copy.

__

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SHORT-CIRCUIT CURRENTS IN THREE-PHASE AC SYSTEMS –

Part 0: Calculation of currents

1

1 GeneralGeneral

1.1

1.1 ScopeScope

This part of IEC 60909 is applicable to the calculation of short-circuit currents: This part of IEC 60909 is applicable to the calculation of short-circuit currents: •• in lin low-ow-volvoltagtage te threhree-e-phaphase se a.ca.c. sy. systestemsms

•• in hin highigh-v-voltoltagage te threhree-e-phaphase se a.ca.c. s. systystememss

operating at a nominal frequency of 50 Hz or 60 Hz. operating at a nominal frequency of 50 Hz or 60 Hz.

Systems at highest voltages of 550 kV and above with long transmission lines need special Systems at highest voltages of 550 kV and above with long transmission lines need special consideration.

consideration.

This part of IEC 60909 establishes a general, practicable and concise procedure leading to results, This part of IEC 60909 establishes a general, practicable and concise procedure leading to results, which are generally of acceptable accuracy. For this calculation method, an equivalent voltage source at which are generally of acceptable accuracy. For this calculation method, an equivalent voltage source at the short-circuit location is introduced. This does not exclude the use of special methods, for example the the short-circuit location is introduced. This does not exclude the use of special methods, for example the superposition method, adjusted to particular circumstances, if they give at least the same precision. The superposition method, adjusted to particular circumstances, if they give at least the same precision. The superposition method gives the short-circuit current related to the one load flow presupposed. This superposition method gives the short-circuit current related to the one load flow presupposed. This method, therefore, does not

method, therefore, does not necessarily lead to the maximum short-circuit current.necessarily lead to the maximum short-circuit current. This part of IEC 60909 deals with the calculation of short-circuit currents in the

This part of IEC 60909 deals with the calculation of short-circuit currents in the case of balancedcase of balanced or unbalanced short circuits.

or unbalanced short circuits.

In case of an accidental or intentional conductive path between one line conductor and local In case of an accidental or intentional conductive path between one line conductor and local earth, the following two cases must be clearly distinguished with regard to their different earth, the following two cases must be clearly distinguished with regard to their different phys

physical ical propproperterties ies and and effeeffects cts (res(resultulting ing in in difdiffereferent nt requrequiremeirements nts for for theitheir car calculculatilati on):on):

•• line-line-to-eto-earth sharth short circort circuit, ocuit, occurricurring in a song in a solidly elidly earthearthed neutrad neutral systel system or an imm or an impedapedancence earthed neutral

earthed neutral systemsystem;;

•• a singa single linele line-to--to-earth earth fault, fault, occuoccurring rring in an isolin an isolated neated neutral eutral earthearthed systed system or a rem or a resonasonancence earthed neutral system. This fault is beyond the scope of, and is therefore not dealt with in, earthed neutral system. This fault is beyond the scope of, and is therefore not dealt with in, this standard.

this standard.

For currents during two separate simultaneous single-phase line-to-earth short circuits in an For currents during two separate simultaneous single-phase line-to-earth short circuits in an isolated neutral system or a resonance earthed neutral system, see IEC 60909-3.

isolated neutral system or a resonance earthed neutral system, see IEC 60909-3.

Short-circuit currents and short-circuit impedances may also be determined by system tests, by Short-circuit currents and short-circuit impedances may also be determined by system tests, by measurement on a network analyzer, or with a digital computer. In existing low-voltage systems measurement on a network analyzer, or with a digital computer. In existing low-voltage systems it is possible to determine the short-circuit impedance on the basis of measurements at the it is possible to determine the short-circuit impedance on the basis of measurements at the location of the

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60909-0

The calculation of the short-circuit impedance is in general based on the rated data of the The calculation of the short-circuit impedance is in general based on the rated data of the electrical equipment and the topological arrangement of the system and has the advantage of electrical equipment and the topological arrangement of the system and has the advantage of bein

being pog possissible ble botboth fh for eor exisxistinting sysg systems tems and and for for systsystems at ems at the the planplanning ning stagstage.e. In general, two short-circuit currents, which differ in

In general, two short-circuit currents, which differ in their magnitude, are to be calculated:their magnitude, are to be calculated:

•• the mthe maximaximum sum short-hort-circucircuit currit current whent which deich determtermines thines the capae capacity or racity or rating of eting of electrlectricalical equipment; and

equipment; and

•• the mthe miniminimum sum short-hort-circcircuit curuit current wrent which chich can be a an be a basisbasis, for e, for examxample, fople, for the ser the selectilection of on of fuses, for the setting

fuses, for the setting of protective devices, and for checking the run-up of motors.of protective devices, and for checking the run-up of motors. NOTE

NOTE The current in a three-phase short circuit is assumed to be made simultaneously in all poles. Investigations of The current in a three-phase short circuit is assumed to be made simultaneously in all poles. Investigations of non-simultaneous short circuits, which may lead to higher aperiodic components of short-circuit current, are beyond non-simultaneous short circuits, which may lead to higher aperiodic components of short-circuit current, are beyond the scope of this standard.

the scope of this standard.

This standard does not cover short-circuit currents deliberately created under controlled This standard does not cover short-circuit currents deliberately created under controlled conditions (short-circuit testing stations).

conditions (short-circuit testing stations). This part of IEC 60909 does not deal with t

This part of IEC 60909 does not deal with t he calculation of short-circuit currents in installationshe calculation of short-circuit currents in installations on board ships and

on board ships and aeroplanes.aeroplanes.

1.2

1.2 Normative referencesNormative references

The following normative documents contain provisions which, through reference in this text, The following normative documents contain provisions which, through reference in this text, constitute provisions of this

constitute provisions of this part of IEC 60909. For part of IEC 60909. For dated references, subsequedated references, subsequent amendments to,nt amendments to, or revisions of, any of

or revisions of, any of these publications do not apply. However, parties to agreements based onthese publications do not apply. However, parties to agreements based on this part of IEC 60909 are encouraged to investigate the possibility of applying the most recent this part of IEC 60909 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO maintain registers of of the normative document referred to applies. Members of IEC and ISO maintain registers of currently valid International Standards.

currently valid International Standards. IEC 60038:1983,

IEC 60038:1983, IEC IEC stanstandard dard voltvoltagesages IEC 60050(131):1978,

IEC 60050(131):1978, Int Internaernatiotional nal ElectElectrotrotechnechnical ical VocabVocabulaulary ry – – ChapChapter ter 131131: : ElecElectric tric and and magnetic circuits

magnetic circuits IEC 60050(151):1978,

IEC 60050(151):1978, Int Internaernatiotional nal ElectElectrotrotechnechnical ical VocabVocabulaulary ry – – ChapChapter ter 151151: : ElecElectric tric and and magnetic devices

magnetic devices IEC 60050-195:1998,

IEC 60050-195:1998, Int Internaernatiotional nal ElecElectrottrotechnechnical ical VocabVocabulaulary ry – – Part Part 195: 195: EartEarthinhing g and and prot

prot ectiection on agaiagainst nst elecelectritric shc shock ock IEC 60056:1987,

IEC 60056:1987, High-v High-voltage oltage alternalternating-cating-currenurrent circt circuit-breuit-breakersakers IEC 60071-1:1993,

IEC 60071-1:1993, Insula Insulation cotion coordinaordination – tion – Part 1Part 1: Defi: Definitions, nitions, principrinciples aples and rulnd ruleses IEC 60781:1989,

IEC 60781:1989, Applic Application ation guide guide for for calcucalculation lation of of short-cshort-circuit ircuit currecurrents nts in in low-vollow-voltage tage radial radial syste

systemsms

IEC 60865-1:1993,

IEC 60865-1:1993, Short-circuit currents – Calculation of effects – Part 1: Definitions and calculationShort-circuit currents – Calculation of effects – Part 1: Definitions and calculation methods

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IEC TR 60909-1,

IEC TR 60909-1,   _{Short-circuit currents calculation in three-phase a.c. systems – Part 1: Factors}_{Short-circuit currents calculation in three-phase a.c. systems – Part 1: Factors}

for the calculation of short-circuit currents in three-phase a.c

for the calculation of short-circuit currents in three-phase a.c. systems according to IEC 60909-0. systems according to IEC 60909-01)1)

IEC TR3 60909-2:1992,

IEC TR3 60909-2:1992, Elect Elect ricarical l equiequipmenpment t – – DatData a for for shoshort-crt-circuircuit it currcurrent ent calccalculaulatiotions ns inin accordance with IEC 60909

accordance with IEC 60909 IEC 60909-3:1995,

IEC 60909-3:1995, Short-circuit current calculation in three-phase a.c. systems – Part 3:Short-circuit current calculation in three-phase a.c. systems – Part 3: Currents during two separate simultaneous single phase line-to-earth short circuits and partial Currents during two separate simultaneous single phase line-to-earth short circuits and partial shor

short-cit-circuircuit cut currenrrents fts f lowilowi ng tng throuhrough gh eartearthh IEC TR 60909-4:2000,

IEC TR 60909-4:2000, Short-circuit current calculation in three-phase a.c. systems – Part 4:Short-circuit current calculation in three-phase a.c. systems – Part 4: Exam

Examples ples for for the the calccalculaulatiotion of n of shorshort-cit-circuircuit cut currenrrentsts IEC 60949:1988,

IEC 60949:1988, Calculation of thermally permissible short-circuit currents, taking intoCalculation of thermally permissible short-circuit currents, taking into account non-adiabatic heating effects

account non-adiabatic heating effects IEC 60986:1989,

IEC 60986:1989, Guide to the short-circuit temperature limits of electrical cables with a rated Guide to the short-circuit temperature limits of electrical cables with a rated voltage from 1,8/3 (3,6) kV to 18/30 (36) kV voltage from 1,8/3 (3,6) kV to 18/30 (36) kV