CEI NORME IEC INTERNATIONALE 60044-7 INTERNATIONAL STANDARD Premiere édition First edition 1999-12 Transformateurs de mesure Partie 7: Transformateurs de tension électroniques Instrument transformers - Part 7: Electronic voltage transformers IEC 1999 Droits de reproduction réservés — Copyright - all rights reserved Aucune partie de cette publication ne peut etre reproduite ni No part of this publication may be reproduced or utilized in utilisée sous quelque forme que ce soit et par aucun procedé, any form or by any means, electronic or mechanical électronique ou mécanique, y compris la photocopie et les including photocopying and microfilm, without permission in microfilms, sans I'accord écrit de I'éditeur. writing from the publisher. International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland Telefax: +41 22 919 0300 IEC web site http://www.iec.ch e-mail: [email protected] CODE PRIX XB Commission Electrotechnique_ Internationale PRICE CODE EC International Electrotechnical Commission MewAyHapoAHa neKTpoTexHuyeCHan KoMuccuA Pour prix, voir catalogue en vigueur For price, see current catalogue 60044-7@IEC:1999 3 CONTENTS Page FOREWORD Clause General 1.1 Scope 9 1.2 Normative references. 1.3 General block diagram of electronic voltage transformers , 13 Definitions. 2 .15 2.1 General definitions.. .15 2.2 Additional definitions for single-phase electronic protective voltage transformers .. .. 27 2.3 Index of symbols.... .27 3 General requirements .. .31 3.1 General... .29 3.2 Information to be given for enquiries, tenders and orders.. Normal and special service conditions 4 .31 4.1 Normal service conditions ... 31 4.2 Special service conditions.. 4.3 Earthing system.. .37 Ratings . 5 .37 5.1 Standard values of rated voltages. .37 5.2 Standard values of rated output . ..39 5.3 Standard values of rated voltage factor.. ..39 5.4 Standard values of rated auxiliary power supply voltage .. 41 5.5 Standard reference values of other influencing parameters. 41 Design requirements.. 6 43 6.1 Insulation requirements for primary voltage sensor. 43 6.2 Insulation requirements for low-voltage components . .51 6.3 Short-circuit withstand capability... .53 6.4 Limits of temperature rise . .53 Radio interference voltage requirements. .53 6.5 6.6 Transmitted overvoltage requirements .. 55 6.7 Electromagnetic compatibility requirements ... .55 Reliability 6.8 59 6.9 Abnormal conditions withstand capability. .61 Abnormal conditions signalling.... 6.10 61 6.11 Mechanical requirements . .61 6.12 Earthing terminals.. .63 Classification of tests ... 7.1 Type tests. .63 7.2 Routine tests .65 7.3 .65 Special tests. - 5 - 60044-7@IEC:1999 Page Clause .65 8 Type tests 8.1 Impulse test on primary voltage terminals . .65 8.2 Wet test for outdoor type electronic voltage transformers. .69 8.3 Tests for accuracy ... 8.4 Test for abnormal conditions withstand capability 71 8.5 Radio interference voltage test .73 8.6 Transmitted overvoltage test.. ..73 8.7 Electromagnetic compatibilitytests .73 8.8 Impulse voltage withstand test for low-voltage components .79 Transient performance tests 8.9 .81 Routine tests.... 9 9.1 Verification of terminal markings ... .81 9.2 Power-frequency withstand tests on primary voltage terminals and partial discharge measurement. Power-frequency voltage withstand test for low-voltage components ... 9.3 ...85 9.4 Tests for accuracy . 10 Special tests. .87 10.1 Chopped lightning-impulse test on primary voltage terminals ... .87 10.2 Measurement of capacitance and dielectric dissipation factor ... . 89 10.3 Mechanical strength tests .. .89 11 Markings... 11.1 Rating plate markings . .. 91 11.2 Terminal markings ... 12 Accuracy requirements for single-phase electronic measuring voltage transformers...... 95 12.1 General requirements .. .95 12.2 Maintenance requirement... ..97 12.3 Accuracy class designation for electronic measuring voltage transformers... 12.4 Standard accuracy classes for electronic measuring voltage t