1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-22283-3 SANS 60974-3:2009Edition 1IEC 60974-3:2007Edition 2SOUTH AFRICAN NATIONAL STANDARD Arc welding equipment Part 3: Arc striking and
4、stabilizing devices This national standard is the identical implementation of IEC 60974-3:2007 and is adopted with the permission of the International Electrotechnical Commission. WARNING Can only be used in conjunction with SANS 60974-1. Published by SABS Standards Division 1 Dr Lategan Road Groenk
5、loof Private Bag X191 Pretoria 0001Tel: +27 12 428 7911 Fax: +27 12 344 1568 www.sabs.co.za SABS SANS 60974-3:2009 Edition 1 IEC 60974-3:2007 Edition 2 Table of changes Change No. Date Scope National foreword This South African standard was approved by National Committee SABS TC 72, Safety of electr
6、ical appliances and electronic equipment, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This SANS document was published in September 2009. IEC 60974-3Edition 2.0 2007-11INTERNATIONAL STANDARD NORME INTERNATIONALEArc welding equipm
7、ent Part 3: Arc striking and stabilizing devices Matriel de soudage larc Partie 3: Dispositifs damorage et de stabilisation de larc INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE RICS 25.160 PRICE CODECODE PRIXISBN 2-8318-9389-5SANS 60974-3:2009This s tandard ma
8、y only be used and printed by approved subscription and freemailing clients of the SABS . 2 60974-3 IEC:2007 CONTENTS FOREWORD.4 1 Scope.6 2 Normative references .6 3 Terms and definitions .6 4 Environmental conditions7 5 Tests 7 5.1 Test conditions7 5.2 Measuring instruments 7 5.3 Conformity of com
9、ponents.7 5.4 Type tests .7 5.5 Routine tests .7 6 Protection against electric shock 8 6.1 Insulation 8 6.2 Protection against electric shock in normal service (direct contact) .9 6.3 Protection against electric shock in case of a fault condition (indirect contact) 9 7 Thermal requirements.9 8 Abnor
10、mal operation 9 9 Thermal protection .10 10 Connection to the input supply network 10 11 Output 10 11.1 Rated peak voltage .10 11.2 Impulse current .11 11.3 Mean energy .14 11.4 Output circuit capacitance discharging 14 12 Control circuits .15 13 Hazard reducing device 15 14 Mechanical provisions 15
11、 15 Rating plate15 16 Adjustment of the output.16 17 Instructions and markings.16 17.1 Instructions .16 17.2 Markings .17 Annex A (informative) Examples of coupling systems for arc striking and stabilizing devices .18 Annex B (informative) Example of a rating plate.19 Figure 1 Rated peak voltage 10
12、Figure 2 Measurement of electric charge of impulse current 11 Figure 3 Arc striking and stabilizing voltage .12 Figure 4 Measuring circuit for direct contact.12 Figure 5 Measuring circuit for serial contact.14 Figure 6 Measuring circuit for capacitance discharging 15 SANS 60974-3:2009This s tandard
13、may only be used and printed by approved subscription and freemailing clients of the SABS .60974-3 IEC:2007 3 Figure A.1 Examples of coupling systems for arc striking and stabilizing devices18 Figure B.1 Stand-alone unit .19 Table 1 Minimum clearances and creepage distances for arc striking and stab
14、ilizing circuits8 Table 2 Maximum rated peak voltages .11 SANS 60974-3:2009This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS . 4 60974-3 IEC:2007 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ ARC WELDING EQUIPMENT Part 3: Arc striking and stabiliz
15、ing devices FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardiz
16、ation in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is
17、 entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the I
18、nternational Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects si
19、nce each technical committee has representation from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical conten
20、t of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible
21、 in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment
22、 declared to be in conformity with an IEC Publication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC Na
23、tional Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications. 8) Attention
24、 is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC sh
25、all not be held responsible for identifying any or all such patent rights. International Standard IEC 60974-3 has been prepared by IEC technical committee 26: Electric welding. This second edition cancels and replaces the first edition published in 2003 and constitutes a technical revision. This edi
26、tion includes the following significant technical changes with respect to the previous edition: changes induced by the publication of IEC 60974-1, edition 3; routine test for built-in unit (see 5.5.2); clarification of calculation of the rated peak voltage (see 11.1 and Figure 1). SANS 60974-3:2009T
27、his s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .60974-3 IEC:2007 5 The text of this standard is based on the following documents: FDIS Report on voting 26/363/FDIS 26/367/RVD Full information on the voting for the approval of this standard can
28、 be found in the report on voting indicated in the above table. This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. This part of IEC 60974 shall be read in conjunction with IEC 60974-1. The list of all the parts of IEC 60974, under the general title Arc welding equip
29、ment, can be found on the IEC web site. The committee has decided that the contents of this publication will remain unchanged until the maintenance result date indicated on the IEC web site under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication w
30、ill be reconfirmed, withdrawn, replaced by a revised edition, or amended. SANS 60974-3:2009This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS . 6 60974-3 IEC:2007 ARC WELDING EQUIPMENT Part 3: Arc striking and stabilizing devices 1 Scope This par
31、t 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 arc striking and arc stabilizing devices that are either connected to a separate welding
32、 power source or built into the welding power source 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 following referenced documents are i
33、ndispensable 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 60974-1:2005, Arc welding equipment Part 1: Welding power sources IEC 60974-7:2005, A
34、rc welding equipment Part 7: Torches 3 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 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
35、 stabilizing device device which superimposes a voltage on the welding circuit to maintain an arc 3.3 arc striking voltage voltage superimposed on the no-load voltage to ignite an arc 3.4 arc stabilizing voltage voltage superimposed on the arc voltage to maintain the arc 3.5 arc striking period peri
36、od during which the arc striking voltage is superimposed on the no-load voltage SANS 60974-3:2009This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .60974-3 IEC:2007 7 4 Environmental conditions As specified in IEC 60974-1, Clause 4. 5 Tests 5.1
37、Test conditions As specified in 5.1 of IEC 60974-1. 5.2 Measuring instruments The accuracy of measuring instruments shall be as follows. a) Electrical measuring instruments: class 0,5 (0,5 % of full-scale reading), except for the measurement of insulation resistance and dielectric strength where the
38、 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. 5.4 Type tests As specified in 5.4 of IEC 60974-1, with the addition of the following
39、requirement. Rated arc striking and stabilizing peak voltage shall be measured in accordance with 11.1 in any convenient sequence of type tests but before verifying mechanical provisions. The other type tests included in this standard may be carried out in any convenient sequence. 5.5 Routine tests
40、5.5.1 Stand-alone unit All routine tests shall be carried out on each stand-alone unit in the following sequence: a) general visual inspection (see 3.7 of IEC 60974-1); b) continuity of the protective circuit (see Clause 10 and, if applicable, 10.4.2 of IEC 60974-1); c) dielectric strength (see 6.1.
41、5 of IEC 60974-1); 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
42、) general visual inspection (see 3.7 of IEC 60974-1). 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. a) High-voltage circuit test: working voltage shall be applied to high-voltage circuits to establish insula
43、tion integrity as specified by the manufacturer. SANS 60974-3:2009This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS . 8 60974-3 IEC:2007 NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects w
44、orking voltage. 6 Protection against electric shock 6.1 Insulation 6.1.1 General As specified in 6.1.1 of IEC 60974-1. 6.1.2 Clearances As specified in 6.1.2 of IEC 60974-1, with the addition of the following requirement. The minimum clearances of high-voltage components shall be in accordance with
45、Table 1. Conformity shall be checked by measurement and visual inspection. 6.1.3 Creepage distances As specified in 6.1.3 of IEC 60974-1, with the addition of the following requirement. The minimum creepage distances of arc striking and stabilizing circuits shall be in accordance with Table 1. Confo
46、rmity shall be checked by measurement and visual inspection. Table 1 Minimum clearances and creepage distances for arc striking and stabilizing circuits Rated peak voltageaClearance bCreepage distancebkV mm mm3 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 ap
47、ply to circuits which are 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. 6.1.5 Dielectric strength The output circuit of arc striking and stabilizing devices
48、and the insulation of coupling components (for example, coupling transformers or coupling capacitors) shall withstand an SANS 60974-3:2009This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .60974-3 IEC:2007 9 arc striking test voltage 20 % higher
49、 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 approximately sine waveform at 50 Hz or 60 Hz may be used for coupling components only. 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 voltage or the a.c. test voltage for 60 s. NOTE Interference
