AS 60044.5-2004 Instrument Transformers - Capacitor .

AS 60044.5—2004IEC/PAS 60044-5:2002AS 60044.5Australian Standard Instrument transformersThis is a free 9 page sample. Access the full version online.Part 5: Capacitor voltage transformers

This Australian Standard was prepared by Committee EL-013, Measurement andProtection Transformers. It was approved on behalf of the Council of StandardsAustralia on 25 November 2003 and published on 30 January 2004.This is a free 9 page sample. Access the full version online.The following are represented on Committee EL-013:Australian Electrical and Electronic Manufacturers AssociationCigre AP12CSIRO Telecommunications and Industrial PhysicsElectricity Supply Association of AustraliaUniversity of South AustraliaKeeping Standards up-to-dateStandards are living documents which reflect progress in science, technology andsystems. To maintain their currency, all Standards are periodically reviewed, andnew editions are published. Between editions, amendments may be issued.Standards may also be withdrawn. It is important that readers assure themselvesthey are using a current Standard, which should include any amendments whichmay have been published since the Standard was purchased.Detailed information about Standards can be found by visiting the Standards WebShop at www.standards.com.au and looking up the relevant Standard in the on-linecatalogue.Alternatively, the printed Catalogue provides information current at 1 January eachyear, and the monthly magazine, The Global Standard, has a full listing of revisionsand amendments published each month.Australian StandardsTM and other products and services developed by StandardsAustralia are published and distributed under contract by SAI Global, whichoperates the Standards Web Shop.We also welcome suggestions for improvement in our Standards, and especiallyencourage readers to notify us immediately of any apparent inaccuracies orambiguities. Contact us via email at mail@standards.org.au, or write to the ChiefExecutive, Standards Australia International Ltd, GPO Box 5420, Sydney, NSW2001.This Standard was issued in draft form for comment as DR 03345.

AS 60044.5—2004Australian Standard Instrument transformersPart 5: Capacitor voltage transformersThis is a free 9 page sample. Access the full version online.Originated as part of AS C45—1928.Previous edition AS 1243—1982.AS 1243—1982 revised and redesignated in part as AS 60044.5—2004.COPYRIGHT Standards Australia InternationalAll rights are reserved. No part of this work may be reproduced or copied in any form or by anymeans, electronic or mechanical, including photocopying, without the written permission of thepublisher.Published by Standards Australia International LtdGPO Box 5420, Sydney, NSW 2001, AustraliaISBN 0 7337 5659 X

iiPREFACEThis Standard was prepared by the Standards Australia Committee EL-013, Measurement andProtection Transformers to partially supersede AS 1243—2982 for capacitor voltagetransformers one year after publication. During this period, it is anticipated that regulatoryauthorities will approve current transformers to either Standard. AS 1243—1982 will continueto apply to three-phase voltage transformers only.The objective of this Standard is to provide users and manufacturers of capacitor voltagetransformers with definitions of terms, safety requirements, methods of specifying performanceand methods of test.This Standard is Part Five of a series covering instrument transformers. The series consists ofthe following Standards:AS60044Instrument transformers60044.1Part 1: Current transformers60044.2Part 2: Single-phase inductive voltage transformers60044.3Part 3: Combined transformers60044.5Part 5: Capacitor voltage transformers (this Standard)This Standard is identical with, and has been reproduced, from IEC/PAS 60044-5:2002,Instrument transformers – Part 5: Capacitor voltage transformers.As this Standard is reproduced from an International Standard, the following applies:(a)Its number does not appear on each page of text and its identity is shown only on thecover and title page.(b)In the source text ‘this international standard’ should read ‘this Australian Standard’.(c)A full point should be substituted for a comma when referring to a decimal marker.(d)Any French text on figures should be ignored.This is a free 9 page sample. Access the full version online.The terms ‘normative’ and ‘informative’ are used to define the application of the annex towhich they apply. A normative annex is an integral part of a standard, whereas an informativeannex is only for information and guidance.

iiiCONTENTSPageThis is a free 9 page sample. Access the full version online.Clause1Scope .12Normative references .13Definitions .343.1 General definitions .33.2 Capacitor voltage divider definitions .63.3 Electromagnetic unit definitions .83.4 Carrier-frequency accessories definitions .9General requirements .95Service conditions .965.1 Normal service conditions .95.2 Special service conditions . 115.3 System earthing . 12Ratings. 1276.1 Standard values of rated frequency . 126.2 Standard values of rated voltages . 126.3 Standard values of rated output. 126.4 Standard values of rated voltage factor . 136.5 Limits of temperature rise . 13Design requirements . 1587.1 Insulation requirements . 157.2 Other insulation requirements. 167.3 Short-circuit withstand capability . 207.4 Ferro-Resonance . 207.5 RIV and TO requirements . 217.6 Mechanical requirements. 227.7 Tightness of capacitor voltage divider and electromagnetic unit. 23Classification of tests . 2398.18.28.38.4TypeType tests . 23Routine tests . 26Special tests . 26Test sequence for one or two units . 26Test . 269.1Temperature-rise test . 269.29.39.49.59.69.79.89.99.10Capacitance and tanδ measurement at power-frequency . 27Short-circuit withstand capability test . 28Impulse tests . 29Wet test for outdoor capacitor voltage transformer . 30Ferro-resonance tests . 31Tightness test of a liquid-filled electromagnetic unit. 32Accuracy tests. 32Transient response test . 33Radio interference voltage test . 35

ivPage10 Routine tests . 3610.1 Tightness of the liquid-filled capacitor voltage divider . 3610.2 Power-frequency withstand test and measurement of capacitance, tanδ andpartial discharge. 3610.3 Verification of terminal markings . 4010.4 Power-frequency withstand tests on the electromagnetic unit . 4010.5 Ferro-resonance check. 4110.6 Accuracy check . 4111 Special Tests. 4211.1 Measurement of the transmission factor of high frequency overvoltages. 4211.2 Mechanical strength test. 4311.3 Determination of the temperature coefficient (T C ) . 4311.4 Tightness design test of capacitor units . 4312 Marking of the capacitor units . 4412.1 General . 4412.2 Marking . 4413 Terminal markings . 4413.1 General . 4413.2 Markings . 4414 Additional requirements for measuring capacitor voltage transformer . 47This is a free 9 page sample. Access the full version online.14.1 Accuracy class designation . 4714.2 Standard reference range of frequency. 4714.3 Standard accuracy classes . 4714.4 Limits of voltage error and phase displacement . 4714.5 Tests for accuracy . 4815 Additional requirements for protective capacitor voltage transformers . 4815.1 Accuracy class designation . 4815.2 Standard reference range of frequency. 4815.3 Standard accuracy classes . 4815.4 Limits of voltage error and phase displacement . 4915.5 Transient response. 4915.6 Requirements for secondary windings intended to produce a residual voltage . 5016 Rating plate . 5316.1 Markings of the rating plate . 5316.2 Example of a typical rating plate. 5517 Requirements for carrier - frequency accessories . 5617.117.217.317.417.5Annex AGeneral . 56Drain coil and voltage limitation device. 56Type tests . 56Routine tests . 57Marking of the rating plate . 57(normative) Typical diagram of a capacitor voltage transformer . 58Annex B (informative) Transient response of capacitor voltage transformer under faultconditions . 60Annex C (normative) High-frequency characteristics of capacitor voltage transformers . 61Bibliography . 62

vThis is a free 9 page sample. Access the full version online.PageFigure 1 – Altitude correction factor for the insulation . 11Figure 2 – Altitude correction factor for the temperature rise . 14Figure 3 – Flow charts test sequence to be applied when performing the type test(figure 3a) and routine test (figure 3b). 25Figure 4 – Diagram of a capacitor voltage transformer for the transient response testusing equivalent circuit method . 34Figure 5 – Series burden . 35Figure 6 – Pure resistance . 35Figure 7 – Test circuit . 38Figure 8 – Alternative circuit . 38Figure 9 – Example of balanced test circuit . 39Figure 10 – Example of calibration circuit. 39Figure 11 – Example of an error diagram of class 1 CVT for accuracy check with theequivalent circuit. 42Figure 12 – Single-phase transformer with a neutral primary terminal and a singlesecondary . 45Figure 13 – Single-phase transformer with a neutral primary terminal and with twosecondaries . 45Figure 14 – Single-phase transformer with a neutral primary terminal and with twotapped secondaries. 45Figure 15 – Single-phase transformer with a neutral primary terminal, with one residualvoltage winding and a single secondary . 46Figure 16 – Error diagram of a capacitor voltage transformer for accuracy classes 0,2,0,5 and 1,0 . 48Figure 17 – Transient response of a capacitor voltage transformer . 49Figure A.1 – Example of a diagram for a capacitor voltage transformer . 58Figure A.2 – Example of a diagram for a capacitor voltage transformer with carrierfrequency accessories . 59Table 1 – Rated ambient temperature categories . 10Table 2 – Standard values of rated voltage factors for accuracy and thermalrequirements. 13Table 3 – Limits of temperature rise of windings . 14Table 4 – Standard insulation levels . 16Table 5 – Partial discharge test voltages and permissible levels . 17Table 6 – Creepage distance . 20Table 7a – Ferro-resonance requirements . 21Table 7b – Ferro-resonance requirements . 21Table 8 – Transmitted overvoltage requirements. 22Table 9 – Static withstand test loads . 22Table 10 – Test voltage for temperature rise test . 27Table 11 – Burden ranges for accuracy tests . 33Table 12 – Test voltages for units, stacks and complete capacitor voltage divider. 37Table 13 – Ferro resonance check . 41Table 14 – Accuracy check points (example) . 42Table 15 – Modalities of application of the test loads to the line primary terminals . 43Table 16 – Limits of voltage error and phase displacement for measuring capacitorvoltage transformers . 47Table 17 – Limits of voltage error and phase displacement for protective capacitorvoltage transformers . 49Table 18 – Standard values . 50Table 19 – Rated secondary voltages for capacitor voltage transformersto produce a residual voltage . 51Table 20 – Marking of the rating plate . 53

This is a free 9 page sample. Access the full version online.viNOTES