1、BRITISH STANDARD BS EN 60247:2004 Insulating liquids Measurement of relative permittivity, dielectric dissipation factor (tan $) and d.c. resistivity The European Standard EN 60247:2004 has the status of a British Standard ICS 17.220.99; 29.040.10 BS EN 60247:2004 This British Standard was published
2、 under the authority of the Standards Policy and Strategy Committee on 26 April 2004 BSI 26 April 2004 ISBN 0 580 43672 1 National foreword This British Standard is the official English language version of EN 60247:2004. It is identical with IEC 60247:2004. It supersedes BS 5737:1979 which is withdr
3、awn. The UK participation in its preparation was entrusted to Technical Committee GEL/10, Fluids for electrotechnical applications, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standar
4、ds which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This p
5、ublication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible interna
6、tional/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN tit
7、le page, pages 2 to 27 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 60247 NORME EUROPENNE EUROPISCHE NORM April 2004 CENELEC European Committee for Ele
8、ctrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2004 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref
9、. No. EN 60247:2004 E ICS 17.220.99; 29.040.10 English version Insulating liquids Measurement of relative permittivity, dielectric dissipation factor (tan ) and d.c. resistivity (IEC 60247:2004) Liquides isolants Mesure de la permittivit relative, du facteur de dissipation dilectrique (tan ) et de l
10、a rsistivit en courant continu (CEI 60247:2004) Isolierflssigkeiten Messung der Permittivittszahl, des dielektrischen Verlustfaktors (tan ) und des spezifischen Gleichstrom- Widerstandes (IEC 60247:2004) This European Standard was approved by CENELEC on 2004-04-01. CENELEC members are bound to compl
11、y 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 Secr
12、etariat 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
13、the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia
14、, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Foreword The text of document 10/573/FDIS, future edition 3 of IEC 60247, prepared by IEC TC 10, Fluids for electrotechnical applications, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60247 on 2004-04-01.
15、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) 2005-01-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2007-04-01 Annex ZA h
16、as been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60247:2004 was approved by CENELEC as a European Standard without any modification. _ Page2 EN60247:200474206 4002:CEI 3 CONTENTS FOERWORD 2 INTRODUCTION. 5 1 Scope. 6 2 Normative references 6 3 Terms and defin
17、itions . 6 4 General 7 4.1 Permittivity and dielectric dissipation factor (tan ) . 7 4.2 Resistivity 8 4.3 Sequence of determinations. 8 4.4 Factors leading to erroneous results 8 5 Apparatus. 9 5.1 Test cell 9 5.2 Test equipment10 5.3 Glassware .10 5.4 Measuring instrument for permittivity and tan
18、.10 5.5 Measuring instrument for d.c. resistivity .10 5.6 Time-measuring device10 5.7 Safety10 6 Cleaning solvent .11 7 Cleaning the test cell 11 7.1 Trisodium phosphate cleaning procedure .11 7.2 Storage of cell .12 8 Sampling 12 9 Preparation of samples.12 10 Conditioning and filling the test cell
19、 .13 10.1 Cell conditioning 13 10.2 Filling the cell 13 11 Test temperature 13 12 Measurement of dissipation factor (tan )14 12.1 Test voltage.14 12.2 Measurement 14 12.3 Report .14 13 Measurement of relative permittivity14 13.1 Measurement 14 13.2 Report .15 14 Measurement of d.c. resistivity15 14.
20、1 Test voltage.15 14.2 Time of electrification 15 14.3 Measurement 15 14.4 Report .16 Page3 EN60247:200474206 4002:CEI 5 Annex A (informative) Example of an alternative procedure for cleaning the test cell Ultrasonic procedure.17 Annex B (informative) Example of a simplified cleaning procedure for a
21、 test cell.18 Annex C (informative) Alternative procedures for routine testing of dielectric dissipation factor and resistivity of insulating liquids19 ugiFrE 1 examfo elp ht aree-etrmlani clle fro maesuremstne sdiuqil no .22 FiugrE 2 examfo elp csrgninee fro eht cfo lle Fiugre 1.32 ugiFrE 3 examfo
22、elp assemd gnilbrawfo gni clel42 ugiFrE 4 examfo elp t awo-etrmlani clle fro maesuremstne diuqil nis.52 FiugrE 5 examfo elp et ast ced llesdengi fro olw-olss eleidctrci sdiuqil 62 Page4 EN60247:2004 60247 IEC:2004 5 xennA ( Aifnroma)evit xEmafo elp retla narp evitancorudef eor clset eht gninaet ce l
23、l tlUrascino procudere.71 xennA B (inform)evita Examfo elp a similpfdei clp gninaerocudere fro et ast clel.81 xennA ( Cifnrom)evita retlArp evitancorudese fro rset enituotfo gni celeidrtci sidsinoitap facrot dna resisytivit fo nisudiuqil gnitals91 Figure 1 Example of a three-terminal cell for measur
24、ements on liquids .22 Figure 2 Example of screening for the cell of Figure 1.23 Figure 3 Example of assembling drawing of cell24 Figure 4 Example of a two-terminal cell for measurements in liquids.25 Figure 5 Example of a test cell designed for low-loss dielectric liquids 26 4egaP 4002:74206NE Annex
25、 ZA (normative) Normative references to international publications with their corresponding European publications . 2774206 4002:CEI 11 INTRODUCTION Health and safety General caution. This International standard does not purport to address all the safety problems associated with its use. It is the r
26、esponsibility of the user of the standard to establish appropriate health and safety practices and determine the applicability of regulatory limitations prior to use. Environment This standard gives rise to insulating liquids, chemicals, used sample containers and oil contaminated solids. The dispos
27、al of these items should be carried out according to local regulations with regard to their impact on the environment. Every precaution should be taken to prevent the release into the environment of these liquids. Page5 EN60247:200474206 4002:CEI 31 INSULATING LIQUIDS MEASUREMENT OF RELATIVE PERMITT
28、IVITY, DIELECTRIC DISSIPATION FACTOR (TAN ) AND DC RESISTIVITY 1 Scope This International standard describes methods for the determination of the dielectric dissipation factor (tan ), relative permittivity and d.c. resistivity of any insulating liquid material at the test temperature. The methods ar
29、e primarily intended for making reference tests on unused liquids. They can also be applied to liquids in service in transformers, cables and other electrical apparatus. However the method is applicable to a single phase liquid only. When it is desired to make routine determinations, simplified proc
30、edures, as described in Annex C, may be adopted. With insulating liquids other than hydrocarbons, alternative cleaning procedures may be required. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition
31、cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60093, Methods of test for volume resistivity and surface resistivity of solid electrical insulating materials IEC 60250, Recommended methods for the determination of the perm
32、ittivity and dielectric dissipation factor of electrical insulating materials at power, audio and radio frequencies including metre wavelengths IEC 60475, Method of sampling liquid dielectrics IEC 61620, Insulating liquids Determination of the dielectric dissipation factor by measure- ment of the co
33、nductance and capacitance Test method 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 permittivity (relative) the relative permittivity of an insulating material is the ratio of capacitance C xof a capacitor in which the space between and aro
34、und the electrodes is entirely and exclusively filled with the insulating material in question, to the capacitance C oof the same configuration of electrodes in vacuum. The capacitance C aof the configuration of electrodes in air can normally be used instead of C o to determine the relative permitti
35、vity with sufficient accuracy Page6 EN60247:200474206 4002:CEI 51 3.2 dielectric dissipation factor (tan ) DDF dielectric dissipation factor, DDF, (tan ) of an insulating material is the tangent of the loss angle. The loss angle is the angle by which the phase difference between applied voltage and
36、the resulting current deviates from /2 rad when the dielectric of the capacitor consists exclusively of the insulating material NOTE For practical purposes, measured values below 0,005 for tan and power factor are essentially the same. A simple conversion can be used to convert one to the other. The
37、 power factor is the sine of the loss angle and the relationship between power factor and dielectric dissipation factor can be expressed as follows: 2 ) ( 1 DDF DDF PF + = (1) 3.3 d.c. resistivity (volume) the volume resistivity of an insulating material is the quotient of a d.c. electrical field st
38、rength and the steady state current density within the material NOTE The unit of resistivity is the ohmmetre ( m). 4 General Permittivity, tan and resistivity, either separately or together, are important indicators of the intrinsic quality and degree of contamination of an insulating fluid. These p
39、arameters may be used to interpret the deviation from desired dielectric characteristics and the potential influence on performance of equipment in which the fluid is used. 4.1 Permittivity and dielectric dissipation factor (tan ) The permittivity and the dielectric dissipation factor (tan ) of elec
40、trical insulating liquids depend to a considerable extent on the test conditions under which they are measured, in particular on the temperature and on the frequency of the applied voltage. Permittivity and dissipation factor are the measurements of dielectric polarization and conductivity of the ma
41、terial. At power frequency and sufficiently high temperature, as recommended in these methods, the losses may be attributable exclusively to the conductivity of the liquid, that is, to the presence of free charge carriers in the liquid. Measurements of the dielectric properties of high purity insula
42、ting liquids are therefore of value as an indication of the presence of contaminants. The dielectric loss factor is usually inversely proportional to the measuring frequency and varies with the viscosity of the medium. The value of the test voltage when measuring the dissipation factor is less impor
43、tant and often governed by the sensitivity of the measuring bridge. However, it must be borne in mind that too high a voltage stress results in secondary phenomena at the electrodes, dielectric heating, discharges etc. While relatively large amounts of impurities produce a comparatively small change
44、 in permittivity, the tan of insulating liquids may be strongly affected by traces of dissolved contaminants or colloidal particles. Some liquids are much more sensitive to contamination than hydrocarbon liquids due to their higher polarity, which results in turn in higher solvent power and dissocia
45、tion capability. Therefore, they require comparatively greater care in handling than hydrocarbon liquids. Page7 EN60247:200474206 4002:CEI 71 Since the initial value is thought to be representative of the actual conditions of the liquid, it appears most desirable that tan should be measured as soon
46、as temperature equilibrium has been reached. Tan is very sensitive to changes of temperature. Its increase, with increases in temperature is generally exponential. It is therefore, necessary to carry out measurements, under sufficiently precise temperature conditions. The procedure described below a
47、llows the test specimen to attain temperature equilibrium with the test cell in minimum time. 4.2 Resistivity The conventional resistivity as measured by this standard is generally not the true resistivity. Application of a d.c. voltage will change the initial characteristics of the liquid with time
48、, due to charge migration. The true resistivity can only be obtained at low voltage, immediately after application of the voltage. This standard uses a relatively high voltage for an extended time and the result will generally be different from that from IEC 61620. Measurements of resistivity of liq
49、uids to this standard, depends on a number of test conditions, namely: a) Temperature Resistivity is very sensitive to changes of temperature, its dependence on the inverse of the temperature, expressed in Kelvin, (1/K) is generally exponential. It is therefore necessary to carry out measurements under sufficiently precise temperature conditions. b)
