1、BRITISH STANDARD BS EN 60404-2:1998 +A1:2008 Magnetic materials Part 2: Methods of measurement of the magnetic properties of electrical steel strip and sheet by means of an Epstein frame ICS 29.030 BS EN 60404-2:1998+A1:2008 This British Standard was published under the authority of the Standards Bo
2、ard and comes into effect on 15 September 1996 BSI 2009 First published February 1985 Second edition August 1996 ISBN 978 0 580 65048 2 National foreword This British Standard is the UK implementation of EN 60404-2:1998+A1:2008. It is identical with IEC 60404-2:1996, incorporating amendment 1:2008.
3、It supersedes BS EN 60404-2:1998 which is withdrawn. The start and finish of text introduced or altered by amendment is indicated in the text by tags. Tags indicating changes to IEC text carry the number of the IEC amendment. For example, text altered by IEC amendment 1 is indicated by !“. The UK pa
4、rticipation in its preparation was entrusted to Technical Committee ISE/NFE/5, Magnetic alloys and steels. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users
5、 are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. Amendments/corrigenda issued since publication Amd. No. Date Comments 10038 July 1998 Renumbers BS 6404-2:1996 as BS EN 60404-2:1998 31 January 2009 Implementation of IEC a
6、mendment 1:2008 with CENELEC endorsement A1:2008i Contents Page Foreword 2 1 Scope and object 3 2 Normative references 3 3 General principles of a.c. measurements 3 4 Procedure for the measurement of the specific total loss 5 5 Procedure for the determination of the peak value of magnetic polarizati
7、on, r.m.s value of magnetic field strength, peak value of magnetic field strength and specific apparent power 7 6 General principles of d.c. measurements 9 7 Procedure for the d.c. measurement of the magnetic polarization 9 8 Test report 10 Annex ZA (normative) Normative references to international
8、publications with their corresponding European publications 19 Figure 1 Double-lapped joints 10 Figure 2 The 25 cm Epstein frame 11 Figure 3 Circuit for the wattmeter method 11 Figure 4 Circuit for measuring the r.m.s value of the magnetizing current 12 Figure 5 Circuit for measuring the peak value
9、of the magnetic field strength using a peak voltmeter 12 Figure 6 Circuit for measuring the peak value of magnetic field strength using a mutual inductor M D 13 Figure 7 Circuit for d.c. testing: to obtain discrete values of magnetic polarization 13 Figure 8 Circuit for d.c. testing: continuous reco
10、rding method 14 Annex A (informative) Digital sampling methods for the determination of the magnetic properties 15 Bibliography 18 BS EN 60404-2:1998+A1:2008 BSI 2008blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 60404-2:1998+A1 July 2008 ICS 29.030 Descriptors: Magnetic materials, measur
11、ement of magnetic properties of electrical steel sheet and strip, general principle, procedure, Epstein frame English version Magnetic materials Part 2: Methods of measurement of the magnetic properties of electrical steel strip and sheet by means of an Epstein frame (IEC 60404-2:1996) Matriaux magn
12、tiques Partie2:Mthodesdemesure des proprits magntiques des tles et bandes magntiques au moyen dun cadre Epstein (CEI 60404-2:1996) Magnetische Werkstoffe Teil2:VerfahrenzurBestimmung der magnetischen Eigenschaften von Elektroblech und -band mit Hilfe eines Epsteinrahmens (IEC 60404-2:1996) This Euro
13、pean Standard was approved by CENELEC on 1998-01-01. CENELEC members 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 reference
14、s concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, Geman). A version in any other language made by translation under the responsibility of a CENELEC member
15、 into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands,
16、Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1998 CENELEC All
17、rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60404-2:1998 E 2 Foreword The text of the International Standard IEC 60404-2:1996, prepared by IEC TC68, Magnetic alloys and steels, was submitted to the formal vote and was approved by CENELEC as
18、 EN 60404-2 on 1998-01-01 without any modification. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. In this standard, Annex ZA is normative. Annex ZA has been added by CENELEC. Endorsement notice The text of the International Standard IEC 60404-2:
19、1996 was approved by CENELEC as a European Standard without any modification. latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1998-12-01 latest date by which the national standards conflicting with the EN ha
20、ve to be withdrawn (dow) 1998-12-01 Foreword to amendment A1 The text of document 68/365/FDIS, future The following dates were fixed: Endorsement notice The text of amendment 1:2008 to the International Standard IEC 60404-2:1996 was approved by CENELEC as an amendment to the European latest date by
21、which the amendment has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2009-03-01 latest date by which the national standards conflicting with the amendment have to be (dow) 2011-06-01 amendment 1 to IEC 60404-2:1996, prepared by IEC TC 6
22、8, Magnetic alloys and steels, was and was approved by CENELEC as amendment A1 to EN 60404-2:1998 on 2008-06-01. submitted to the IEC-CENELEC parallel vote Standard without any modification. BS EN 60404-2:1998+A1:2008 BSI 2008withdrawn 3 1 Scope and object This part of IEC404 is applicable to grain
23、oriented and non-oriented electrical sheet and strip for a.c. measurements of magnetic properties at frequencies up to 400Hz and for d.c. magnetic measurements. The object of this part is to define the general principles and the technical details of the measurement of the magnetic properties of elec
24、trical steel sheet and strip by means of an Epstein frame. The Epstein frame is applicable to test specimens obtained from electrical steel sheets and strips of any grade. The a.c. magnetic characteristics are determined for sinusoidal induced voltages, for specified peak values of magnetic polariza
25、tion and for a specified frequency. The measurements are to be made at an ambient temperature of (23 5) C on test specimens which have first been demagnetized. Measurements at higher frequencies are to be made in accordance with IEC404-10. NOTEThroughout this standard the term “magnetic polarization
26、” is used as defined in IEC50(221). In some standards of the IEC404 series, the term “magnetic flux density” was used. 2 Normative references 3 General principles of a.c. measurements 3.1 Principle of the 25 cm Epstein frame method The 25cm Epstein frame which comprises a primary winding, a secondar
27、y winding and the specimen to be tested as a core, forms an unloaded transformer whose characteristics are measured by the method described in the following subclauses. 3.2 Test specimen The strips to be tested are assembled in a square, having double-lapped joints (see Figure 1), thus forming four
28、branches of equal length and equal cross-sectional area. The strips shall be sampled in accordance with the appropriate product standard in the IEC404-8 series. They shall be cut by a method which will produce substantially burr-free edges and, if so specified, heat treated in accordance with the co
29、rresponding product standard. They shall have the following dimensions: width b = 30mm 0,2mm; length 280mm k l k 320mm. The lengths of the strips shall be equal within a tolerance of 0,5 mm. When strips are cut parallel or normal to the direction of rolling, the edge of the parent sheet shall be tak
30、en as the reference direction. The following tolerances shall apply for the angle between the specified and actual direction of cutting: 1 for grain oriented steel sheet; 5 for non-oriented steel sheet. Only flat strips shall be used. Measurements shall be made without additional insulation. BS EN 6
31、0404-2:1998+A1:2008 BSI 2008 !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 (including any amendments) applies. IEC 60050-221, Inte
32、rnational Electrotechnical Vocabulary Chapter 221: Magnetic materials and components IEC 60404-4, Magnetic materials Part 4: Methods of measurement of d.c. magnetic properties of magnetically soft materials IEC 60404-8-3, Magnetic materials Part 8-3: Specifications for individual materials Cold- rol
33、led electrical non-alloyed and alloyed steel sheet and strip delivered in the semi-processed state IEC 60404-8-4, Magnetic materials Part 8-4: Specifications for individual materials Cold- rolled non-oriented electrical steel sheet and strip delivered in the fully-processed state IEC 60404-8-7, Magn
34、etic materials Part 8-7: Specifications for individual materials Cold- rolled grain-oriented electrical steel sheet and strip delivered in the fully-processed state IEC 60404-10, Magnetic materials Part 10: Methods of measurement of magnetic properties of magnetic sheet and strip at medium frequenci
35、es IEC 60404-13, Magnetic materials Part 13: Methods of measurement of density, resistivity and stacking factor of electrical steel sheet and strip “ 4 The number of strips comprising the test specimen shall be a multiple of four and is specified in the corresponding product standard. However, the a
36、ctive mass of the test specimen see equation (1) shall be at least 240g for strips 280mm long. 3.3 The 25 cm Epstein frame The 25cm Epstein frame (hereinafter referred to as the Epstein frame) shall consist of four coils into which the strips making up the test specimen are inserted (see Figure 2).
37、A mutual inductor for air flux compensation is included with the Epstein frame. The winding formers supporting the coils are made of hard insulating material, such as phenolic paper. They have a rectangular cross-section with 32mm inner width. A height of approximately 10mm is recommended. The coils
38、 shall be fixed to an insulating and non-magnetic base in such a way as to form a square (seeFigure 2). The length of the sides of the square formed by the internal edges of the strips of the test specimen shall bemm (seeFigure 2). Each of the four coils shall have two windings: a primary winding, o
39、n the outside (magnetizing winding); a secondary winding, on the inside (voltage winding). NOTEAn electrostatic screen may be provided between these windings. The windings shall be distributed uniformly over a minimum length of 190mm, each coil having one quarter of the total number of turns. The in
40、dividual primary windings of the four coils shall be connected in series, as shall be the secondary windings. The number of primary and secondary turns may be adapted to the particular conditions prevailing with regard to the power source, measuring equipment and frequency. NOTEThe total number of t
41、urns generally used and recommended is700 or 1000. In order to reduce the effect of the impedances of the windings as much as possible, the following requirements shall be met: NOTEThese requirements are satisfied, for example, if windings with the following characteristics are used: total number of
42、 turns: N 1= 700, N 2= 700; primary (outer) winding: each of the four coils carries 175 turns of two copper wires connected in parallel, each with a nominal cross-sectional area of approximately 1,8 mm 2 , wound side by side in three layers; secondary winding: each of the four coils carries 175 turn
43、s of one copper wire with a nominal cross-sectional area of 0,8 mm 2wound in one layer. The effective magnetic path length, lm, of the magnetic circuit shall be conventionally assumed to be equal to 0,94 m. Therefore, the active mass, m a , that is the mass of the test specimen which is magnetically
44、 active, is given by: 3.4 Air flux compensation The mutual inductor for air flux compensation shall be located in the centre of the space enclosed by the four coils, its axis being directed normal to the plane of the axes of these coils. The primary winding of the mutual inductor shall be connected
45、in series with the primary winding of the Epstein frame, and the secondary winding of the mutual inductor shall be connected to the secondary winding of the Epstein frame in series opposition (seeFigure 3). 220 +1 0 where R 1and R 2 are the resistances of the primary and secondary windings, respecti
46、vely, in ohms; L 1and L 2 are the inductances of the primary and secondary windings, respectively, in henrys; N 1and N 2 are the total number of turns of the primary and secondary windings, respectively. (1) where l is the length of a test specimen strip, in metres; l m is the conventional effective
47、 magnetic path length, in metres (l m= 0,94 m); m is the total mass of the test specimen, in kilograms; m a is the active mass of the test specimen, in kilograms. ma lm4l -m = BS EN 60404-2:1998+A1:2008 BSI 20085 The adjustment of the value of the mutual inductance shall be made so that, when passin
48、g an alternating current through the primary windings in the absence of the specimen in the apparatus, the voltage measured between the non-common terminals of the secondary windings shall be no more than 0,1% of the voltage appearing across the secondary winding of the test apparatus alone. Thus the average value of the rectified voltage induced in the combined secondary windings is proportional to the peak value of the magnetic polarization in the test specimen. 3.5 Power supply The power supply shall have a low impedance and a high stability of voltage and frequency. During measure
