1、BRITISH STANDARD BS EN 60052:2002 Voltage measurement by means of standard air gaps The European Standard EN 60052:2002 has the status of a British Standard ICS 19.080 BS EN 60052:2002 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 10 July 2
2、003 BSI 10 July 2003 ISBN 0 580 42228 3 National foreword This British Standard is the official English language version of EN 60052:2002. It is identical with IEC 60052:2002. It supersedes BS 358:1960 which will be withdrawn on 2005-11-01. The UK participation in its preparation was entrusted to Te
3、chnical Committee PEL/42, Testing techniques for high voltages and currents, 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 Standards which implement international or European publicatio
4、ns 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 publication does not purport to include all the necessar
5、y provisions of a contract. Users are responsible for their 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 international/European committee any enquiries on the interp
6、retation, 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 title page, pages 2 to 29 and a back cover. The BSI copy
7、right date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 60052 NORME EUROPENNE EUROPISCHE NORM November 2002 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Norma
8、lisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2002 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60052:2002 E ICS 19.080 English version Vol
9、tage measurement by means of standard air gaps (IEC 60052:2002) Mesure de tension au moyen des clateurs sphres normaliss (CEI 60052:2002) Empfehlungen fr Spannungsmessungen mit Standard-Luftfunkenstrecken (IEC 60052:2002) This European Standard was approved by CENELEC on 2002-11-01. CENELEC members
10、are bound to comply 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 t
11、o the Central Secretariat 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 t
12、he same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerla
13、nd and United Kingdom.Foreword The text of document 42/173/FDIS, future edition 3 of IEC 60052, prepared by IEC TC 42, High-voltage testing techniques, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60052 on 2002-11-01. The following dates were fixed: latest date by
14、 which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2003-08-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2005-11-01 Annexes designated “normative“ are part of the body of t
15、he standard. Annexes designated “informative“ are given for information only. In this standard, annex ZA is normative and annex A to D are informative. Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60052:2002 was approved by CENELEC as a European
16、 Standard without any modification. _ Page2 EN60052:20022002:CEI 25006 3 CONTENTS INTRODUCTION.4 1 Scope.5 2 Normative references5 3 Definitions5 4 Standard sphere-gap 5 4.1 Requirements on shape and surface conditions .5 4.2 General arrangement of a sphere-gap for measurement.6 4.3 Connections7 5 U
17、se of the sphere-gap 8 5.1 Condition of the sphere surfaces9 5.2 Irradiation9 5.3 Voltage measurements 9 6 Reference values in tables 2 and 3 .10 6.1 Accuracy of values in tables 2 and 3 11 6.2 Air density correction factor .11 6.3 Humidity correction factor 12 7 Standard rod-rod gap for measurement
18、 of direct voltage .12 7.1 General arrangement of a rod-rod gap .12 7.2 Reference values.12 7.3 Measurement procedure12 8 Use of standard air gaps for performance checks of approved measuring systems 13 Annex A (informative) Range of experimental calibrations for sphere-gaps .23 Annex B (informative
19、) Procedure by which the values in tables 2 and 3 have been derived from national standards and other sources24 Annex C (informative) Sources of irradiation.25 Annex D (informative) Uncertainty and calibration of sphere-gaps.26 Annex ZA (normative) Normative references to international publications
20、with their corresponding European publications 27 Bibliography28 Figure 1 Vertical sphere-gap 20 Figure 2 Horizontal sphere-gap.21 Figure 3 Arrangement for rod-rod gap.22 Table 1 Clearance limits.7 Table 2 Peak values of disruptive discharge voltages (U 50values in impulse tests) in kV for alternati
21、ng voltages at power frequencies, full lightning and switching impulse voltages of negative polarity and direct voltages of both polarities14 Table 3 Peak values of disruptive discharge voltages (U 50values in impulse tests) in kV for full lightning and switching impulse voltages of positive polarit
22、y17 Table A.1 Experimental calibrations of the sphere-gap23 Table B.1 Rounding off of values in tables 2 and 324 Page3 EN60052:20022002:CEI 25006 4 INTRODUCTION Sphere-gaps have been used as a simple and reliable method for measurement of peak voltage in many industrial test facilities for 75 years,
23、 and the values of tables I and II in the second edition of IEC 60052 have been accepted as an International Consensus Standard of Measurements. These tables appear in this standard as tables 2 and 3. There is no information in the references (e.g. annex A) with regard to traceability to national st
24、andards of measurement. However, the dispersion in the measured values of sparkover voltages upon which tables 2 and 3 are based, does not exceed 3 % for a 95 % confidence level. In view of the long history of IEC 60052 as an International Consensus Standard of Measurement, the values for disruptive
25、 discharge voltage in tables I and II of the second edition of IEC 60052 are reproduced in this publication as tables 2 and 3. They are to be used as mean values with an uncertainty of 3 % for a 95 % confidence level. The material on rod-rod gaps for reliable measurement of high direct voltages has
26、been included here to form an integrated standard on high voltage measurements using standard air gaps. Four informative annexes are included: Annex A gives the limits of voltage and frequency over which tables 2 and 3 have been derived from experiments and can be presumed to be accurate within the
27、limits specified in 4.1. Annex B gives the procedure by which the values in tables 2 and 3 have been derived from previous national standards and other sources. Annex C provides information on additional irradiation, which may be needed in certain situations. Annex D provides information on the unce
28、rtainty and calibration of sphere-gaps. Page4 EN60052:20022002:CEI 25006 5 VOLTAGE MEASUREMENT BY MEANS OF STANDARD AIR GAPS 1 Scope IEC 60052 sets forth recommendations concerning the construction and use of standard air gaps for the measurement of peak values of the following four types of voltage
29、: a) alternating voltages of power frequencies; b) full lightning impulse voltages; c) switching impulse voltages; d) direct voltages. Air gaps constructed and used in accordance with this standard represent IEC standard measuring devices in accordance with IEC 60060-2 and are primarily intended for
30、 performance checks of high voltage measuring systems. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (includ
31、ing any amendments) applies. IEC 60060-1:1989, High-voltage test techniques Part 1: General definitions and test requirements IEC 60060-2:1994, High-voltage test techniques Part 2: Measuring systems 3 Definitions vacant 4 Standard sphere-gap The standard sphere-gap is a peak voltage measuring device
32、 constructed and arranged in accordance with this standard. The points on the two spheres which are closest to each other are called the sparking points. Figures 1 and 2 show two arrangements, one of which is typical of sphere-gaps with a vertical axis and the other of sphere-gaps with a horizontal
33、axis. 4.1 Requirements on shape and surface conditions The standard sphere-gap consists of two metal spheres of the same diameter D, their shanks, operating gear, insulating supports, supporting frame and leads for connection to the point at which the voltage is to be measured. Standard values of D
34、are 2 5 6,25 10 12,5 15 25 50 75 100 150 and 200 cm. The spacing between the spheres is designated S. Page5 EN60052:20022002:CEI 25006 6 The spheres shall be carefully made so that their surfaces are smooth and their curvature is as uniform as possible. The tolerances on size and shape need usually
35、only be checked when the spheres are first supplied and any suitable instrument (e.g. spherometer) may be used. The diameter of each sphere shall not differ by more than 2 % from the nominal value. The spheres shall be reasonably free from surface irregularities in the region of the sparking point.
36、A medium grade mechanical surface finishing (roughness R maxbelow 10 m) is considered to be adequate. The region of the sparking point is defined by a circle such as would be drawn on the spheres by a pair of dividers set to an opening of 0,3 D and centred in the sparking point. When the sphere-gap
37、is used, it will normally be sufficient to examine the surface by touch and visual inspection. NOTE Any minor damage on the non-adjacent hemispherical surfaces does not alter the sphere-gap performance. 4.2 General arrangement of a sphere-gap for measurement 4.2.1 Vertical gap When the spheres are a
38、rranged vertically, the shank of the high-voltage sphere shall be free from sharp edges or corners and the diameter of the shank shall not exceed 0,2 D over a length D. This requirement is made in order to reduce the influence of the high-voltage shank on the disruptive discharge voltage. If a stres
39、s distributor (corona shield) is used at the end of the shank, its greatest dimension, perpendicular to the axis of the spheres, shall not exceed 0,5 D and shall be at least 2 D from the sparking point of the high-voltage sphere. The earthed shank and the operating gear have a smaller effect and the
40、ir dimensions are therefore less important. Figure 1 gives the limits of size of the components of a typical vertical sphere-gap. The sphere shanks should be visually in line. 4.2.2 Horizontal gap When the spheres are arranged horizontally, the limiting dimensions of a typical sphere-gap are given i
41、n figure 2. They are the same for both sides of the gap. The sphere shanks should be visually in line. 4.2.3 Height of the spheres above the horizontal earth plane The height A of the sparking point of the high-voltage sphere above the earth plane of the laboratory floor shall be within the limits g
42、iven in table 1. If the sphere-gap is mounted with the earthed sphere nearest to the ceiling, and if other surfaces such as walls and the floor are at a considerably greater distance, then the ceiling shall be regarded as the horizontal plane, from which the distance A is measured downwards. Page6 E
43、N60052:20022002:CEI 25006 7 4.2.4 Clearance around the spheres The distance from the sparking point of the high-voltage sphere to any extraneous objects (such as ceiling, walls, and any energized or earthed equipment), and also to the supporting frame work for the spheres, if this is made of conduct
44、ing material, shall not be less than the value of distance B in table 1. Except as permitted below, B should not be less than 2 D, regardless of the value of S. Supporting frameworks for the spheres made of insulating material are exempt from this requirement, provided that they are clean and dry an
45、d that the spheres are used for the measurement of alternating or impulse voltages only. The distance B between the sparking point of the high-voltage sphere and the framework may then be less than is prescribed in table 1, however, it shall not be less than 1,6 D. The peak values of disruptive disc
46、harge voltages in tables 2 and 3 are valid for clearances around the spheres within the limits given in table 1. Table 1 Clearance limits Sphere diameter D cm Minimum value of height A Maximum value of height A Minimum value of distance B Up to 6,25 10 -15 25 50 75 100 150 200 7 D 6 D 5 D 4 D 4 D 3,
47、5 D 3 D 3 D 9 D 8 D 7 D 6 D 6 D 5 D 4 D 4 D 14 S 12 S 10 S 8 S 8 S 7 S 6 S 6 S The test conditions may make it impossible for the values of A and B to comply with the minimum requirements. Such sphere-gaps can be used, providing that, either the conventional deviation z meets the requirements of cla
48、use 5, or, that the uncertainty in the values for disruptive discharge in tables 2 and 3 are suitably increased. Such sphere-gaps could be calibrated under laboratory conditions as indicated in annex D. The circuit should be arranged so that at the test voltage there is no disruptive discharge to ot
49、her objects, no visible leader discharge from the high-voltage lead or the shank within the space defined by B, no visible discharge from other earthed objects extending into the space defined by B. 4.3 Connections The sphere-gap shall be connected in accordance with the requirements specified in IEC 60060-2. 4.3.1 Earthing One sphere normally shall be connected directly to earth. Low ohmic shun
