1、Synthetic organic esters for electrical purposes - Guide for maintenance of transformer esters in equipment The European Standard EN 61203 : 1994 has the status of a British Standard EC 1203 : 1992 CENELEC EN+bl1203 94 = 3404583 0356896 4bb Amd. No. BS EN 61203 : 1995 Date Text affected This British
2、 Standard, having been prepared under the direction of the Electrotechnical Sector Board, was published under the authority of the Standards Board and comes into effect on 15 June 1995 0 BSI 1995 Committees responsible for this British Standard The preparation of this British Standard was entrusted
3、to Rchnical Committee GELJ10, Fluids for electrotechnical applications, upon which the following bodies were represented: British Cable Makers Confederation British Lubricants Federation Limited Chemical Industries Association Electricity Association Health and Safety Executive Institute of Petroleu
4、m Institution of Electrical Engineers London Regional Transport National Association of Waste Disposal Contractors Transmission and Distribution Association (BEAMA Ltd.) The foilowing BSI references relate to the work on this standard: Committee reference GEL/10 Draft for comment 86120278 DC ISBN O
5、580 24173 4 CENELEC EN*bL203 94 3404583 OL5b897 3T2 BS EN 61203 : 1995 Contents Committees responsible Page Inside front cover National foreword ii Foreword 2 Qxt of EN 61203 3 i CENELEC EN*b1203 94 = 3404583 O15b898 239 BS EN 61203 : 1996 National foreword This British Standard has been prepared by
6、 “chnical Committee GEU10 and is the English language version of EN 61203 : 1994 Synthdic organic esters for electrical purposes - Guide for maintenance of transfomLer esters in equipmnt, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 120
7、3 : 1992, published by the International Electrotechnical Commission (IEC). WAR“G. This British Standard calls for the use of substances and procedures that may be injurious to health if adequate precautions are not taken. It refers only to technical suitability and does not absolve the user from le
8、gal obligations relating to health and safety at any stage. Cross-references hbiication referred to HD 397 S1 : 1979 (IEC 599 : 1978) EN 60567 : 1992 (IEC 567 : 1992) EN 61099 : 1992 (IEC 1099 : 1992) Compliance with a British Standard does not of itself confer immunity from legal obligations. Corre
9、sponding British Standard BS 5800 : 1979 Guide for the imtion of the analysis of gases in tranqfm and otk oil-filled electrical equiprnmt in sernuice BS EN 60567 : 1993 Guide for the sampling of gases and of oil frwn oil-filled electrical equiprnmt and fw the analysis of free and dissolved gases Bs
10、EN 61099 : 1992 Spccat.iOn for unused synthdic organic esters for electrical purposes ii CENELEC ENxb3203 94 H 3404583 0356899 375 H EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 61203 September 1994 ICs 29. 180 : 29.040.20 Descriptors: Electrical equipment, transformers, electrical insulatin
11、g liquid, esters, organic matter, characteristics, tests, classification, maintenance English version Synthetic organic esters for electrical purposes Guide for maintenance of transformer esters in equipment (IEC 1203 : 1992) Esters organiques de synthse usages lectriques - Guide de maintenance des
12、esters pour transformateurs dans les matriels (CE1 1203 : 1992) Betriebsmitteln Synthetische organische Ester fr elektrotechnische Zwecke Leitlinie zur Wartung von Transformator-Estern in (IEC 1203 : 1992) This European Standard was approved by CENELEC on 1994-03-08. CENELEC members are bound to com
13、ply with the CENKENELEC 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 Sec
14、retariat 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
15、 the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Elect
16、rotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels O 1994 Copyright reserved to CENELEC members Ref. No. EN 61203 : 1994 E CENELEC ENtb3203 94 3404583 0356900 737 = me 2
17、 EN 61203 : 1994 Foreword The CENELEC questionnaire procedure, performed for finding out whether or not the International Standard IEC 1203 : 1992 could be accepted without textual changes, has shown that no common modifications were necessary for the acceptance as European Standard. The reference d
18、ocument was submitted to the CENELEC members for formal vote and was approved by CENELEC as EN 61203 on 8 March 1994. The foiiowing dates were fixed : - latest date of publication of an identical national standard (dop) 1995-03-15 - iatest date of withdrawal of conflicting national standards (dw) 19
19、95-03-15 Annexes designated normative are part of the body of the standard. In this standard, annex ZA is normative. CENELEC ENxbL203 94 = 3404583 OL5690L 653 9 Page 3 BS EN 61203 : 1994 CONTENTS clause page Scope . Normative references . Tests and their significance 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8
20、3.9 3.10 Colour and appearance Density Kinematic viscosity . Water content Neutralization value Breakdown voltage . D.C. resistivity Flash point - Fire point . Dielectric dissipation factor Diagnosis by gas analysis (IEC 567 and IEC 599) . Frequency of examination of liquids in service . Sampling Te
21、sting procedures . 6.1 Field screening tests . 6.2 Laboratory tests Classification of esters in service . Treatment of ester liquids in group 2 . 8.1 Vacuum treatment and filtration 8.2 Molecular sieve and filtration . Materials used for maintenance equipment Annex ZA (normative) Other international
22、 publications quoted in this standard with the references of the relevant European publications . 4 4 4 5 5 5 5 5 5 6 6 6 6 6 6 6 7 7 7 8 8 8 8 9 CENELEC ENJbL203 94 3404583 0356902 59T = Page 4 BS EN 61203 : 1994 SYNTHETIC ORGANIC ESTERS FOR ELECTRICAL PURPOSES - GUIDE FOR MAINTENANCE OF TRANSFORME
23、R ESTERS IN EQUIPMENT 1 scope This International Standard is a guide to the maintenance of synthetic organic esters, originally complying with the requirements of IEC 1099, in transformers with rated voltages up to 35 kV. It is intended to assist the equipment operator in assessing the quality of th
24、e liquid during use in the equipment and maintaining it in a serviceable condition. Methods for reconditioning ester transformer liquid are outlined. This standard deals only with ester liquid used in equipment where liquid sampling is practicable and which has not previously been filled with any ot
25、her liquid. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and par
26、ties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IEC 567: 1992, Guide for the sa
27、mpling of gases and of oil from oil-filled electrical equipment and for the analysis of free and dissolved gases IEC 599: 1978, Interpretation of the analysis of gases in transformers and other oil-filled electrical equipment in service IEC 1099: 1992, Specifications for unused synthetic organic est
28、ers for electrical purposes 3 Tests and their significance There are several tests which can be applied to transformer synthetic organic esters to determine their suitability for further use or whether corrective action is necessary. The appropriate method of test is indicated by cross reference to
29、clause 9, “Test methods, of IEC 1099. CENELEC EN*b3203 94 m 3404583 0356703 42b Page 5 BS EN 61203 : 1994 Propetfy Subclause of IEC 7099 Colour and appearance Density Kinematic viscosity Flash point Fire point Water content Neutralization value Breakdown voltage D.C. resistivity Dielectric dissipati
30、on factor 9.1f9.2 9.3 9.4 9.5 9.6 9.10 9.1 1 9.13 9.14 9.14 3.1 Colour and appearance The liquid shall be clear without visible contamination. It shall not be excessively dark in colour and shall not have an acrid odour. 3.2 Density Changes in density may suggest contamination with other liquids or
31、materials. 3.3 Kinematic viscosity Changes in viscosity suggest contamination with other liquids, or possibly serious degra- dation due to severe and prolonged overheating. 3.4 Flash point - Fire point Diminution of the flash point or fire point indicates contamination with other liquids and/or liqu
32、id degradation. A significant reduction of the fire point and flash point could indicate a fauli in the transformer. Other properties may also have changed. 3.5 Water content A value above that specified in clause 7 indicates undesirable operating conditions which need corrective action, as outlined
33、 in clause 8. 3.6 Neutralization value An increase in the neutralization value of an ester indicates deterioration by oxidation and/or hydrolysis. A value above that specified in clause 7 indicates an undesirable liquid condition which may accelerate solid insulation deterioration. CENELEC EN*b11203
34、 94 3404583 01156904 362 Page 6 BS EN 61203 : 1994 3.7 Breakdown voltage An unsatisfactory value may be due to the presence of water or particulate contamination, or degradation of the liquid. Remedial treatment of the liquid as described in clause 8 should be considered. 3.8 D.C. resistivity A redu
35、ced value suggests contamination with water or with other soluble impurities. Treatment of the liquid as described in clause 8 should be considered. 3.9 Dielecric dissipation factor An increased value may well indicate degradation of the ester liquid or contamination with water or other impurities.
36、Remedial treatment of the liquid should be considered. 3.1 O Diagnosis by gas analysis (IEC 567 and IEC 599) Ester liquids will produce a mixture of gases on thermal decomposition due to high temperature hot spots, arcing and breakdown under electrical stress conditions. These will be similar to tho
37、se produced from mineral oil (see IEC 567 and IEC 599) but no information is as yet available to allow interpretation of gas analysis data. 4 Frequency of examlnation of liquids In servlce It is not possible to specify a frequency of examination which will meet all equipment designs and operating co
38、nditions. Where practicable, samples of ester should be taken and analyzed before energizing, after twelve months, and thereafter at five year intervals. Heavily loaded and higher voltage units, with rated voltage greater than 35 kV, may require more frequent testing. Increased frequency is also adv
39、isable where any of the significant properties approaches the limit recommended for continued service or shows an increased rate of change. 5 Sampling Sampling should be carried out during or as soon as possible after normal operation by the procedures described in clause 8 of IEC 1099. It is impera
40、tive that all precautions described in the method are adhered to, in order to avoid erroneous test resuits and retesting. 6 Testing procedures In general, no one test can be used as the sole criterion of the condition of an ester in service. Evaluation of the condition of a liquid should preferably
41、be based upon the value of significant characteristics as determined in adequately equipped laboratories. However, field screening tests are widely used. CENELEC EN*b1203 94 3404583 0156905 2T9 Page 7 BS EN 61203 : 1994 6.1 Field screening tests Field screening tests are usually made to determine wh
42、ich samples require laboratory investigation. Field tests are usually limited to visual inspection and breakdown voltage. However, portable instruments are available that can be used for field measurements of d.c. resistivity, dielectric dissipation factor, neutralization value and water content. 6.
43、2 Laboratory tests These include most or all of the tests listed in clause 3 as these often enable the cause of degradation or source of contamination to be recognized. 7 Classification of esters in service Based on current industrial experience, esters in service can be classified as follows: GROUP
44、 1 This group includes liquids that are in satisfactory condition for continued use. The values of the following properties are considered to be satisfactory for 35 kV or lower voltage equipment. - Appearance clear - Water content I; 400 mgkg - Neutralization value I 2,O mg KOH/g - Breakdown voltage
45、 30 kV - Dielectric dissipation factor, - D.C. resistivity at ambient temperature 2 6 G a.m at ambient temperature s 0,Ol - Fire point 300 “C GROUP 2 This group includes liquids which require only minor reconditioning for further service. This will be indicated by a cloudy or dirty appearance, highe
46、r moisture content and lower breakdown voltage. The appropriate treatment is outlined in clause 8. Treatment should result in a significant improvement of the condition of the ester with values for breakdown voltage and water content tending to approach those indicated by the manufacturer at commiss
47、ioning. CENELEC ENxb1203 94 3404583 0356906 135 Page 8 BS EN 61203 : 1994 GROUP 3 This group includes liquids which cannot be restored to a satisfactory condition by the methods outlined in clause 8. Such esters should be returned to the supplier or disposed of in accordance with local regulations.
48、8 Treatment of ester Ilqulds in group 2 Reconditioning may be carried out by one of the following two methods using equipment commensurate with the quantity of liquid to be processed. 8.1 Vacuum treatment and filtration The ester liquid, preferably heated at 60 OC to 80 OC. shall be passed into a va
49、cuum chamber by spraying or by flow over baffle plates to give a large surface area of liquid. The pressure shall be as low as possible, 0,l kPa or less as attainable in practice. A filter of 5 pm to 10 pm pore size shall be placed on the exit side of the unit. 8.2 Molecular sieve and filtration The ester liquid shall be passed through a bed of dried molecular sieve beads at ambient temperature, and then, filtered at 5 pm to 10 pm nominal pore size. NOTE - If the material cannot be rendered usable ater reconditioning it should be disposed of as described in cla
