1、BSI Standards PublicationArc welding equipmentPart 3: Arc striking and stabilizing devicesBS EN 60974-3:2014National forewordThis British Standard is the UK implementation of EN 60974-3:2014. It is identical to IEC 60974-3:2013. It supersedes BS EN 60974-3:2007 which is withdrawn.The UK participatio
2、n in its preparation was entrusted to TechnicalCommittee WEE/6, Electric arc welding equipment.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions ofa contract. Users are responsibl
3、e for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 77229 0ICS 25.160.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Poli
4、cy and Strategy Committee on 31 May 2014.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN 60974-3:2014EUROPEAN STANDARD EN 60974-3 NORME EUROPENNE EUROPISCHE NORM February 2014 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Norma
5、lisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B - 1000 Brussels 2014 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60974-3:2014 E ICS 25.160 Supersede
6、s EN 60974-3:2007 English version Arc welding equipment - Part 3: Arc striking and stabilizing devices (IEC 60974-3:2013) Matriel de soudage larc - Partie 3: Dispositifs damorage et de stabilisation de larc (CEI 60974-3:2013) Lichtbogenschweieinrichtungen - Teil 3: Lichtbogenznd- und -stabilisierung
7、seinrichtungen (IEC 60974-3:2013) This European Standard was approved by CENELEC on 2013-12-31. 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-
8、to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by tr
9、anslation under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic
10、, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS E
11、N 60974-3:2014EN 60974-3:2014 - 2 - Foreword The text of document 26/518/FDIS, future edition 3 of IEC 60974-3, prepared by IEC/TC 26 “Electric welding“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 60974-3:2014. The following dates are fixed: latest date by which the
12、document has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2014-09-30 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2016-12-31 This document supersedes EN 60974-3:2007. EN 60974-3:20
13、14 includes the following significant technical changes with respect to EN 60974-3:2007: changes induced by the publication of IEC 60974-1:2012. This standard is to be read in conjunction with EN 60974-1:2012. Attention is drawn to the possibility that some of the elements of this document may be th
14、e subject of patent rights. CENELEC and/or CEN shall not be held responsible for identifying any or all such patent rights. This standard covers the Principle Elements of the Safety Objectives for Electrical Equipment Designed for Use within Certain Voltage Limits (LVD - 2006/95/EC). Endorsement not
15、ice The text of the International Standard IEC 60974-3:2013 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following note has to be added for the standard indicated : IEC 60974 NOTE Harmonized in EN 60974 series (not modified).
16、 BS EN 60974-3:2014- 3 - EN 60974-3:2014 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dat
17、ed references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publication Year
18、Title EN/HD Year IEC 60974-1 2012 Arc welding equipment Part 1: Welding power sources EN 60974-1 2012 IEC 60974-7 - Arc welding equipment Part 7:Torches EN 60974-7 - IEC 61140 - Protection against electric shock - Common aspects for installation and equipment EN 61140 - BS EN 60974-3:2014 2 60974-3
19、IEC:2013 CONTENTS 1 Scope 6 2 Normative references 6 3 Terms and definitions 6 4 Environmental conditions . 7 5 Tests . 7 5.1 Test conditions 7 5.2 Measuring instruments . 7 5.3 Conformity of components . 7 5.4 Type tests 7 5.5 Routine tests 7 5.5.1 Stand-alone unit . 7 5.5.2 Built-in unit . 8 6 Pro
20、tection against electric shock . 8 6.1 Insulation . 8 6.1.1 General 8 6.1.2 Clearances . 8 6.1.3 Creepage distances 8 6.1.4 Insulation resistance . 9 6.1.5 Dielectric strength . 9 6.2 Protection against electric shock in normal service (direct contact) 10 6.3 Protection against electric shock in cas
21、e of a fault condition (indirect contact) . 10 6.4 Protective provision . 10 7 Thermal requirements 10 8 Thermal protection 10 9 Abnormal operation . 10 10 Connection to the supply network 11 11 Output . 11 11.1 Rated peak voltage 11 11.2 Impulse current 12 11.2.1 Risk of electric shock 12 11.2.2 El
22、ectric charge 12 11.2.3 Direct contact . 12 11.2.4 Series contact. 13 11.3 Mean energy 14 11.4 Output circuit capacitance discharging . 15 12 Control circuits 15 13 Hazard reducing device . 15 14 Mechanical provisions . 15 15 Rating plate . 15 16 Adjustment of the output 16 17 Instructions and marki
23、ngs 16 17.1 Instructions 16 17.2 Markings 17 BS EN 60974-3:201460974-3 IEC:2013 3 Annex A (informative) Examples of coupling systems for arc striking and stabilizing devices . 18 Annex B (informative) Example of a rating plate . 19 Bibliography 20 Figure 1 Rated peak voltage 11 Figure 2 Measurement
24、of electric charge of impulse current 12 Figure 3 Measuring circuit for direct contact . 13 Figure 4 Measuring circuit for serial contact . 14 Figure 5 Measurement of mean energy 14 Figure 6 Measuring circuit for capacitance discharging 15 Figure A.1 Examples of coupling systems for arc striking and
25、 stabilizing devices 18 Figure B.1 Stand-alone unit . 19 Table 1 Minimum clearances and creepage distances for arc striking and stabilizing circuits 9 Table 2 Maximum peak voltages 11 BS EN 60974-3:2014 6 60974-3 IEC:2013 ARC WELDING EQUIPMENT Part 3: Arc striking and stabilizing devices 1 Scope Thi
26、s part of IEC 60974 specifies safety requirements for industrial and professional arc striking and arc stabilizing devices used in arc welding and allied processes. This part of IEC 60974 is applicable to stand-alone units which may be connected to a separate welding power source or one where the we
27、lding power source and the arc striking and arc stabilizing device are housed in a single enclosure. NOTE 1 Typical allied processes are for example plasma arc cutting and arc spraying. NOTE 2 This standard does not include electromagnetic compatibility (EMC) requirements. 2 Normative references The
28、 following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60974-
29、1:2012, Arc welding equipment Part 1: Welding power sources IEC 60974-7, Arc welding equipment Part 7: Torches IEC 61140, Protection against electric shock Common aspects for installation and equipment 3 Terms and definitions For the purposes of this document, the terms and definitions given in IEC
30、60974-1 and IEC 60974-7, as well as the following, apply. 3.1 arc striking device device which superimposes a voltage on the welding circuit to ignite an arc 3.2 arc stabilizing device device which superimposes a voltage on the welding circuit to maintain an arc 3.3 arc striking voltage voltage supe
31、rimposed on the no-load voltage to ignite an arc 3.4 arc stabilizing voltage voltage superimposed on the arc voltage to maintain the arc BS EN 60974-3:201460974-3 IEC:2013 7 3.5 arc striking period period during which the arc striking voltage is superimposed on the no-load voltage 4 Environmental co
32、nditions As specified in IEC 60974-1:2012, Clause 4. 5 Tests 5.1 Test conditions As specified in 5.1 of IEC 60974-1:2012. 5.2 Measuring instruments The accuracy of measuring instruments shall be as follows: a) electrical measuring instruments: class 1 (1 % of full-scale reading), except for the meas
33、urement of insulation resistance and dielectric strength where the accuracy of the instruments is not specified, but shall be taken into account for the measurement; b) thermometer: 2 K; c) high-voltage probe: 5 %. 5.3 Conformity of components As specified in 5.3 of IEC 60974-1:2012. 5.4 Type tests
34、As a condition of conformity, the type tests given below shall be carried out on stand-alone units in the following sequence with no drying time between f), g) and h): a) general visual inspection, as defined in 3.7 of IEC 60974-1:2012; b) insulation resistance, as specified in 6.1.4 of IEC 60974-1:
35、2012 (preliminary check); c) enclosure, as specified in 14.2 of IEC 60974-1:2012; d) handling means, as specified in 14.3 of IEC 60974-1:2012; e) drop withstand, as specified in 14.4 of IEC 60974-1:2012; f) protection provided by the enclosure, as specified in 6.2.1 of IEC 60974-1:2012; g) insulatio
36、n resistance, as specified in 6.1.4 of IEC 60974-1:2012; h) dielectric strength, as specified in 6.1.5 of IEC 60974-1:2012; i) general visual inspection, as defined in 3.7 of IEC 60974-1:2012. Rated arc striking and stabilizing peak voltage shall be measured in accordance with 11.1 in any convenient
37、 sequence of type tests but before verifying mechanical provisions. The other type tests included in this document and not listed here shall be carried out in any convenient sequence. 5.5 Routine tests 5.5.1 Stand-alone unit All routine tests shall be carried out on each stand-alone unit in the foll
38、owing sequence: BS EN 60974-3:2014 8 60974-3 IEC:2013 a) general visual inspection (as defined in 3.7 of IEC 60974-1:2012); b) continuity of the protective circuit (as specified in Clause 10 and, if applicable, 10.5.1 of IEC 60974-1:2012); c) dielectric strength (as specified in 6.1.5 of IEC 60974-1
39、:2012); d) high-voltage circuit test: working voltage shall be applied to high-voltage circuits to establish insulation integrity as specified by the manufacturer; NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects working voltage. e) general v
40、isual inspection (as defined in 3.7 of IEC 60974-1:2012). 5.5.2 Built-in unit The following routine test shall be carried out on each built-in unit in any convenient sequence for the power source (as specified in 5.5 of IEC 60974-1:2012): High-voltage circuit test: working voltage shall be applied t
41、o high-voltage circuits to establish insulation integrity as specified by the manufacturer. NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects working voltage. 6 Protection against electric shock 6.1 Insulation 6.1.1 General As specified in 6.1
42、.1 of IEC 60974-1:2012. 6.1.2 Clearances The minimum clearances for high-voltage components shall be in accordance with Table 1. The minimum clearance for other components shall be in accordance with 6.1.2 of IEC 60974-1:2012. Conformity shall be checked by measurement and visual inspection. 6.1.3 C
43、reepage distances The minimum creepage distances for arc striking and stabilizing circuits shall be in accordance with Table 1. The minimum creepage distances for other components shall be in accordance with 6.1.3 of IEC 60974-1:2012. Conformity shall be checked by measurement and visual inspection.
44、 BS EN 60974-3:201460974-3 IEC:2013 9 Table 1 Minimum clearances and creepage distances for arc striking and stabilizing circuits Rated peak voltageaClearancebCreepage distancebkV mm mm 3 3 6,3 6 5,5 10 8 8 12,5 10 11 16 12 14 20 15 18 25 18 25 30 20 30 35 NOTE These values apply to circuits which a
45、re designed in accordance with 11.3.aRated peak voltage shall be measured in accordance with 11.1. bInterpolation is allowed. 6.1.4 Insulation resistance As specified in 6.1.4 of IEC 60974-1:2012. 6.1.5 Dielectric strength The output circuit of arc striking and stabilizing devices and the insulation
46、 of coupling components (for example, coupling transformers or coupling capacitors) shall withstand an arc striking test voltage 20 % higher than the rated peak arc striking voltage at the maximum pulse repetition rate of the device. Alternatively, an a.c. test voltage with the same peak value of ap
47、proximately sine waveform at 50 Hz or 60 Hz may be used for coupling components only. The maximum permissible setting of the tripping current shall be 100 mA. The high voltage transformer shall deliver the prescribed voltage up to the tripping current. Tripping is regarded as a flashover or a breakd
48、own. NOTE 1 For the operators safety, the lowest setting of the tripping current (less than or equal to 10 mA) is typical. Conformity shall be checked by the following test. Coupling components intended for use with arc striking and stabilizing voltages shall be subjected to the arc striking test vo
49、ltage or the a.c. test voltage for 60 s. NOTE 2 Interference suppression capacitors are not coupling devices. The output circuit shall be subjected to the arc striking test voltage for 60 s applied between the point of connection to the welding electrode and a) exposed conductive parts; b) other isolated circuits. Flashover or breakdown shall not occur. Any discharges unaccompanied by a voltage drop (corona) are disregarded. NOTE 2 Interference suppression capacitors are subjected to the tes
