IEC 60909 0 2001 Short Circuit Current_Resumen

INTERNATIONAL STANDARD

IEC IE C 60909-0 First edition 2001-07

Short-circuit currents in three-phase a.c. systems – Part 0: Calculation of currents

This English-language  version is derived from the original  bilingual   publication by leaving out all French-language  pages.  pag es. Missi Mis sing ng page pag e numbe nu mbers rs corre cor respo spond nd to the th e Frenc Fre nchhlanguage pages.

Reference number  IEC 60909-0:2001(E)

INTERNATIONAL STANDARD

IEC IE C 60909-0 First edition 2001-07

Short-circuit currents in three-phase a.c. systems – Part 0: Calculation of currents

©  IEC

2001 Copyright - all rights reserved

No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying photocopying and microfilm, without permission in writing from the publisher.

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CONTENTS FOREWORD................................ FOREWORD..................................................... .......................................... ........................................... ........................................... ............................... .......... 9

1

2

3

4

General General ......... .............. .......... ......... ......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... .......... ........... ........... ....... 13 1.1 Scope Scope .......... ............... ......... ......... .......... .......... ......... ......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... ......... ......... .......... ..... 13 1.2 Normativ Normativee referenc references es .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... 15 1.3 Definitio Definitions ns .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... .. 17 1.4 Symbols, Symbols, subscript subscriptss and superscript superscripts...... s........... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... .. 25 1.4.1 Symbols Symbols .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... ......... ......... ....... .. 25 1.4.2 Subscript Subscriptss .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... 29 1.4.3 Superscr Superscripts ipts .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ........ ... 31 Characte Characteristi ristics cs of short-c short-circui ircuitt currents: currents: calcula calculating ting method method..... .......... .......... ........... ........... .......... .......... ........... ........... ..... 31 2.1 General.. General....... .......... .......... .......... .......... .......... .......... .......... ......... ......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... ......... .... 31 2.2 Calculat Calculation ion assump assumptions...... tions........... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... 35 2.3 Method Method of calcu calculatio lation n .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ..... 35 2.3.1 Equivalen Equivalentt voltag voltagee source source at at the the shortshort-circ circuit uit location location .......... ................ ............ ............ ........... ....... 35 2.3.2 Applicati Application on of symmet symmetrica ricall compone components nts .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... ..... 41 2.4 Maximum Maximum short-ci short-circuit rcuit currents currents .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ..... 45 2.5 Minimum Minimum short-c short-circui ircuitt currents currents .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... 47 Short-ci Short-circuit rcuit impeda impedances nces of electrica electricall equipment... equipment........ .......... .......... .......... .......... .......... .......... .......... .......... ........... ........... .......... ..... 47 3.1 General.. General....... .......... .......... .......... .......... .......... .......... .......... ......... ......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... ......... .... 47 3.2 Network Network feeders feeders .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......... .... 49 3.3 Transfor Transformer merss .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......... .... 51 3.3.1 Two-windi Two-winding ng transfor transformer merss .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... 51 3.3.2 Three-w Three-windin inding g transform transformers ers .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......... .... 53 3.3.3 Impeda Impedance nce correctio correction n factors factors for two- and three-win three-winding ding network transformers transformers ................................................ .......................................................................... .................................... .......... 57 3.4 Overhea Overhead d lines and and cables cables .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......... .... 59 3.5 Short-ci Short-circuit rcuit limiting limiting reactors reactors .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ........ ... 61 3.6 Synchrono Synchronous us machin machines es .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......... .... 61 3.6.1 Synchron Synchronous ous gene generator ratorss .......... ............... .......... .......... .......... .......... .......... .......... .......... ......... ......... .......... .......... .......... .......... ....... 61 3.6.2 Synchrono Synchronous us comp compensa ensators tors and motors motors .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... ....... .. 65 3.7 Power Power station station unit .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... 65 3.7.1 Power Power station station units with on-load on-load tap-chan tap-changer....... ger............ .......... .......... .......... .......... .......... .......... .......... ....... 65 3.7.2 Power Power station station units without without on-lo on-load ad tap-chan tap-changer....... ger............ .......... .......... .......... .......... .......... .......... ....... 69 3.8 Asynchr Asynchronous onous motors......... motors.............. .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... .. 71 3.8.1 General General .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ..... 71 3.8.2 Contributio Contribution n to short-ci short-circuit rcuit currents currents by asynchr asynchronous onous motors motors ............ .................. ......... ... 73 3.9 Static Static converte converters...... rs........... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ........ ... 77 3.10 Capacitor Capacitorss and non-rotat non-rotating ing loads loads .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ....... .. 77 Calculati Calculation on of short-ci short-circuit rcuit currents currents .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ........ ... 79 4.1 General.. General....... .......... .......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... ......... .......... .......... .......... .......... .......... ......... ......... .......... .......... ......... .... 79 4.2

Initia Initiall sym symme metri trical cal shortshort-cir circui cuitt curr current ent  I k ′′ ........................................... ............................................................... .................... 83

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4.3 4.3

4.4 4.5

4.6 4.6

4.7 4.8

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4.2.1 Three-p Three-phase hase short short circuit.... circuit......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ..... 83 4.2.2 Line-toLine-to-line line short short circui circuitt .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......... .... 95 4.2.3 Line-toLine-to-line line short short circui circuitt with earth earth connect connection.. ion....... .......... .......... .......... ........... ........... .......... ........... ........ 99 4.2.4 Line-toLine-to-eart earth h short short circuit circuit .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......101 .101 Peak Peak sho short rt--circ circui uitt curr curren entt i p ............................................ .................................................................. ..........................................101 ....................101 4.3.1 Three-p Three-phase hase short short circuit.... circuit......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .........10 ....101 1 4.3.2 Line-toLine-to-line line short circuit .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ........10 ...105 5 4.3.3 Line-toLine-to-line line short short circuit with earth earth connection connection..... .......... .......... .......... .......... .......... .......... .......... .........10 ....105 5 4.3.4 Line-toLine-to-eart earth h short short circuit circuit .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......107 .107 DC compone component nt of the short-c short-circu ircuit it current current .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... ........107 ...107 Symm Symmetr etrica icall short short-c -circ ircuit uit break breaking ing curren currentt I  b ...........................................................107 4.5.1 Far-from Far-from-ge -genera nerator tor short circuit circuit .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......107 ..107 4.5.2 Near-toNear-to-gen generat erator or short circuit .......... ............... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .........10 ....109 9 Stea Steady dy-s -sta tate te shor shortt-ci circ rcuit uit cur curre rent nt I   I k  .................................................................. ...............................117 ........117 k  ........................................... 4.6.1 Three-ph Three-phase ase short circuit circuit of of one generator generator or one one power power station station unit .......... ...........117 .117 4.6.2 Three-p Three-phase hase short short circuit circuit in non-mes non-meshed hed network networks......... s.............. .......... .......... .......... ........... ..........12 ....121 1 4.6.3 Three-p Three-phase hase short short circuit circuit in meshed meshed networks....... networks............ .......... ........... ........... .......... .......... .......... ........123 ...123 4.6.4 Unbalanc Unbalanced ed short circuits...... circuits........... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... .......... ......123 .123 4.6.5 Short Short circuits circuits at at the low-v low-voltag oltagee side of transfor transformer mers, s, if one one line line conducto conductor  r  is interrupted at the high-voltage side ......................................................... ..........................................................125 .125 Terminal Terminal short short circuit of asynchrono asynchronous us motors....... motors............ .......... .......... .......... .......... .......... .......... .......... .......... ..........1 .....127 27 Joule integr integral al and therm thermal al equivale equivalent nt short-ci short-circuit rcuit curren currentt .......... ............... .......... ........... ............ ........... .......129 ..129

Annex A (normative) (normative)

Equations for the calculation of the factors m and n ........................137

Figure 1 – Short-circuit current of a far-from-gener far-from-generator ator short circuit with constant a.c. component component (schematic (schematic diagram)................................... diagram)....................................................... .....................................31 .................31 Figure 2 – Short-circuit current of a near-to-generator near-to-generator short circuit with decaying a.c. component component (schematic (schematic diagram) diagram) ...................................... .......................................................... .................................33 .............33 Figure 3 – Characterization Characterization of short circuits and their currents..............................................37 currents..............................................37 Figure 4 – Illustration for calculating the initial symmetrical symmetrical short-circuit current  I k ′′ in compliance with the procedure for the equivalent voltage source source ......................................39 ......................................39 Figure 5 – Short-circuit impedances of a three-phase a.c. system at the short-circuit short-circuit location F................................... F....................................................... ....................................... ....................................... ..........................43 ......43 Figure 6 – System diagram and equivalent equivalent circuit diagram for network feeders .....................49 Figure 7 – Three-winding Three-winding transformer (example) (example) ...................................... .......................................................... ............................55 ........55 Figure 8 – Phasor diagram of a synchronous generator generator at rated conditions ............................63 ............................63 Figure 9 – Example for the estimation of the contribution from the asynchronous motors motors in relation to the total short-circuit short-circuit current........................................ current.............................................................. ....................................75 ..............75 Figure 10 – Diagram to determine the short-circuit type (figure 3) for the highest short-circuit current referred to the symmetrical symmetrical three-phase short-circuit current at the short-circuit location when the impedance impedance angles of the sequence impedances  Z (1) ....................................................... ..................................... ............................81 ..........81 (1) ,  Z (2) (2) ,  Z (0) (0) are identical .................................... Figure 11 – Examples of single-fed single-fed short circuits............................... circuits.................................................... ...................................85 ..............85 Figure 12 – Example Example of a non-meshed non-meshed network ..................................... ....................................................... ................................89 ..............89

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Figure 13 – Short-circuit currents and partial short-circuit currents for three-phase three-phase short circuits between generator and unit transformer transformer with or without on-load tap-changer, tap-changer, or at the connection to the auxiliary transformer of a power station unit and at the auxiliary busbar A .................................... ....................................................... ..................................... .................................... .................................... .....................89 ...89 Figure 14 – Example of a meshed meshed network fed from several sources......................................97 sources......................................97 Figure 15 – Factor κ  for  for series circuit as a function of ratio R ratio  R// X   X  or  or  X / R  R ...............................101 Figure 16 – Factor µ  for  for calculation of short-circuit breaking current I  current I  b ..............................111 Figure 17 – Factor q  for the calculation of the symmetrical symmetrical short-circuit breaking current of asynchronous asynchronous motors ................................... ...................................................... ...................................... ....................................113 .................113 Figure 18 – λ min .........................................119 min  and λ max max  factors for cylindrical rotor generators .........................................119 Figure 19 – Factors λ min generators .......................................... ...............................................119 .....119 min  and λ max max  for salient-pole generators Figure 20 – Transformer secondary short circuits, if one line (fuse) is opened on the high-voltage high-voltage side of a transformer Dyn5 .................................... ....................................................... ....................................... ...................... .. 125 Figure 21 – Factor m for the heat effect of the d.c. component of the short-circuit current (for programming, the equation for m is given in annex A)................................... A)..................................................131 ...............131 Figure 22 – Factor n  for the heat effect of the a.c. component of the short-circuit current (for programming, the equation for n is given in annex A) A) ................................... ..................................................133 ...............133 Table 1 – Voltage factor c .................................. ................................................... .................................. .................................. .................................41 ................41 Table 2 – Factors α  and   and β  for  for the calculation of short-circuit currents with equation (90) Rated transformation ratio t r r  = U rTHV ................................................. .................................. .........................127 ........127 r THV / U rTLV rTLV ................................ Table 3 – Calculation of short-circuit currents of asynchronous asynchronous motors in the case of  a short circuit at the terminals (see (see 4.7) ....................................... ............................................................. .......................................129 .................129

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INTERNATIONAL ELECTROTECHNICAL COMMISSION

 ____________  SHORT-CIRCUIT CURRENTS IN THREE-PHASE AC SYSTEMS –  Part 0: Calculation of currents

FOREWORD 1) The IEC (International (International Electrotechnical Electrotechnical Commission) Commission) is a worldwide worldwide organization organization for standardization standardization comprising 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 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  particip  part icipate ate in this prepa ratory rato ry work. Internat Inte rnational ional , govern mental and non-go vernmen tal organ izati ons liai sing 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. 2) The formal formal decisions or agreements agreements of the IEC on technical technical matters express, express, as nearly as as possible, an international international consensus of opinion on the relevant subjects since each technical committee has representation from all interested National Committees. 3) The documents documents produced produced have the form of recomm recommendations endations for international international use and are published in the form of  standards, technical specifications, technical reports or guides and they are accepted by the National Committees in that sense. 4) In 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  betwee n the IEC Standard Stan dard and the corre spond ing nati onal or regio nal stand ard shall shal l be clearly clear ly indi cated in the latter. 5) The 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. 6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of 

 paten t ri ghts. The I EC s hall not be he ld r espons ible for ident ifyin g any or all a ll such paten t right r ights. s.

International Standard IEC 60909-0 has been prepared by IEC technical committee 73: Shortcircuit currents. This first edition cancels and replaces IEC 60909 published in 1988 and constitutes a technical revision. The text of this standard is based on the following documents: FD IS

R ep or t on vot i n g

73 / 1 1 9/ FD IS

7 3/ 12 1 / R VD

Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table. Annex A forms an integral part of this standard.

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This part of IEC 60909 shall be read in conjunction with the International Standards, Technical Reports and Technical Specifications mentioned below:  –

IEC TR 60909-1,— Short-circuit current calculation in three-phase a.c. systems – Part 1:  Factors for the calculation calcula tion of short-circuit short-c ircuit currents in three-phase three-ph ase a.c. systems according  accordin g  1) to IEC 60909-0

 –

IEC TR3 T R3 60909 6 0909-2:1 -2:1992, 992, Elec  Electri trical cal equipmen equi pmentt – Data for short-ci shor t-circui rcuitt curre c urrent nt calcula calc ulatio tions ns in accordance with IEC 60909

 –

IEC 60909-3: 6090 9-3:1995 1995,, 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   part ial short-c shor t-circu ircuit it currents curr ents follow fol lowing ing through thr ough earth eart h

 –

IEC TR T R 60909-4 60 909-4:200 :2000, 0, Short-circuit current calculation in three-phase a.c. systems – Part 4:  Examples  Exam ples for the calcula cal culatio tion n of short-ci shor t-circui rcuitt curren cu rrents ts

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

reconfirmed;

•

wi t h d r awn ;

•

repl replac aced ed by a rev revis ised ed editi edition on,, or  or 

•

amended.

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

 ____  _______ ____  _  1)

To be published.

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SHORT-CIRCUIT CURRENTS IN THREE-PHASE AC SYSTEMS –  Part 0: Calculation of currents

1 1.1

General Scope

This part of IEC 60909 is applicable to the calculation of short-circuit currents: •

in lowlow-vol voltag tagee thre threee-pha phase se a.c. a.c. syste systems ms

•

in high high-v -volt oltag agee thre threee-pha phase se a.c. a.c. syst system emss

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 consideration. 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 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 gives the short-circuit current related to the one load flow presupposed. This method, therefore, does not necessarily lead to the maximum short-circuit current. This part of IEC 60909 deals with the calculation of short-circuit currents in the case of balanced or unbalanced short circuits. 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  physical  phys ical propert prop erties ies and effects effe cts (result (res ulting ing in differe dif ferent nt requireme requ irements nts for their thei r calcu ca lculati lati on): •

line-to-e line-to-earth arth short short circuit, circuit, occurri occurring ng in a solidly solidly earthe earthed d neutral neutral system system or an impeda impedance nce earthed neutral system; system;

•

a single single line-toline-to-earth earth fault, occurring occurring in an isolated isolated neutral neutral earthe earthed d system system or a resona resonance nce earthed neutral system. This fault is beyond the scope of, and is therefore not dealt with in, this standard.

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. 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 it is possible to determine the short-circuit impedance on the basis of measurements at the location of the prospective short circuit considered.

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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   being  bein g possi po ssible ble both bot h for f or exis e xistin ting g systems sys tems and for systems syst ems at the planning plan ning stage. stag e. In general, two short-circuit currents, which differ in their magnitude, are to be calculated: •

the maxim maximum um shortshort-circu circuit it current current which which determ determines ines the the capacity capacity or rating rating of electr electrical ical equipment; and

•

the minim minimum um shortshort-circ circuit uit current current which which can can be a basis, basis, for exam example, ple, for for the selecti selection on of  fuses, for the setting of protective devices, and for checking the run-up of motors.

 NOTE 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 the scope of this standard.

This standard does not cover short-circuit currents deliberately created under controlled conditions (short-circuit testing stations). This part of IEC 60909 does not deal with t he calculation of short-circuit currents in installations on board ships and aeroplanes. 1.2

Normative references

The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC 60909. For dated references, subsequent subsequent amendments to, or revisions of, any of these 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 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  currently valid International Standards. IEC 60038:1983, IEC 60038:1983, IEC standard stan dard voltages volt ages IEC 60050(131):1978,  Interna  Int ernatio tional nal Electrot Elect rotechn echnical ical Vocabula Vocab ulary ry – Chapter Chap ter 131: 131 : Electric Elec tric and  magnetic circuits IEC 60050(151):1978,  Interna  Int ernatio tional nal Electrot Elect rotechn echnical ical Vocabula Vocab ulary ry – Chapter Chap ter 151: 151 : Electric Elec tric and  magnetic devices IEC 60050-195:1998,  Interna  Int ernatio tional nal Electrot Elec trotechn echnical ical Vocabula Vocab ulary ry – Part 195: Earthin Eart hing g and   prot ection ecti on against agai nst electri elec tricc shock  sh ock  IEC 60056:1987, High-v 60056:1987, High-voltage oltage alternating-c alternating-curren urrentt circuit-bre circuit-breakers akers IEC 60071-1:1993, Insula 60071-1:1993, Insulation tion coordina coordination tion – Part 1: 1: Definitions, Definitions, principles principles and and rules rules IEC 60781:1989,  Application  Application guide for calculation calculation of short-circuit short-circuit currents currents in low-voltage low-voltage radial   systems  systems IEC 60865-1:1993, Short-circuit currents – Calculation of effects – Part 1: Definitions and calculation methods

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IEC TR 60909-1,   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. a.c. systems according to IEC 60909-01) IEC TR3 60909-2:1992,  Elect rical rica l equipmen equi pmentt – Data Dat a for short-c sho rt-circu ircuit it current curr ent calcula calc ulatio tions ns in accordance with IEC 60909 IEC 60909-3:1995, 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   short-ci  shor t-circui rcuitt curren cu rrents ts f lowi ng throu t hrough gh earth eart h IEC TR 60909-4:2000, Short-circuit current calculation in three-phase a.c. systems – Part 4:  Examples  Exam ples for the calcula calc ulatio tion n of short-ci shor t-circui rcuitt curren cu rrents ts IEC 60949:1988, Calculation of thermally permissible short-circuit currents, taking into account non-adiabatic heating effects IEC 60986:1989, 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 

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To be published.