1、September 2007DEUTSCHE NORM English price group 10No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 25.160.10!$I5.“13818
2、11www.din.deDDIN EN ISO 17657-1Resistance welding Welding current measurement for resistance welding Part 1: Guidelines for measurement (ISO 17657-1:2005)English version of DIN EN ISO 17657-1:2007-09Widerstandsschweien Schweistrommessung fr das Widerstandsschweien Teil 1: Leitfaden fr die Messung (I
3、SO 17657-1:2005)Englische Fassung DIN EN ISO 17657-1:2007-09SupersedesDIN ISO 17657-1:2006-02www.beuth.deDocument comprises 18 pages 11.07DIN EN ISO 17657-1:2007-09 2 National foreword This standard has been prepared by Technical Committee ISO/TC 44 “Welding and allied processes”, Subcommittee SC 6
4、“Resistance welding” (Secretariat: DIN, Germany) and has been adopted as EN ISO 17657-1:2007 by Technical Committee CEN/TC 121 “Welding”. The responsible German body involved in its preparation was the Normenausschuss Schweitechnik (Welding Standards Committee), Joint Committee NA 092-00-12 AA Wider
5、standsschweien (DVS AG V 3). DIN EN ISO 17657 consists of the following parts, under the general title Resistance welding Welding current measurement for resistance welding: Part 1: Guidelines for measurement Part 2: Welding current meter with current sensing coil Part 3: Current sensing coil Part 4
6、: Calibration system Part 5: Verification of welding current measuring system The DIN Standard corresponding to the International Standard referred to in the EN is as follows: ISO 669 DIN ISO 669 Amendments This standard differs from DIN ISO 17657-1:2006-02 as follows: a) The text of ISO 17657-1 has
7、 been adopted by CEN without any modification. Previous editions DIN ISO 17657-1: 2006-02 National Annex NA (informative) Bibliography DIN ISO 669, Resistance welding Resistance welding equipment Mechanical and electrical requirements EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 17657-1
8、June 2007 ICS 25.160.10 English Version Resistance welding - Welding current measurement for resistance welding - Part 1: Guidelines for measurement (ISO 17657-1:2005) Soudage par rsistance - Mesurage des courants en soudage par rsistance - Partie 1: Lignes directrices pour le mesurage (ISO 17657-1:
9、2005) Widerstandsschweien - Schweistrommessung fr das Widerstandsschweien - Teil 1: Leitfaden fr die Messung (ISO 17657-1:2005) This European Standard was approved by CEN on 19 May 2007. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for givi
10、ng 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 CEN Management Centre or to any CEN member. This European Standard exists in three official ver
11、sions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgiu
12、m, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR ST
13、ANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 17657-1:2007: EContents Page Foreword Intro
14、duction 1 Scope . 2 Normative references . 3 Terms and definitions. 4 Welding current measuring system 4.1 General. 4.2 Applicability. 4.3 Accuracy 4.4 Welding current meter with current sensing coil 5 Current sensors 5.1 Type of sensor 5.2 Selection of current sensor . 5.3 Conversion coefficient .
15、6 7 Annex C (informative) Conversion coefficient and maximum output voltage of current sensing 2 EN ISO 17657-1:2007 (E) . 3457891012 131555777999Tests and calibration of the welding current measuring systems Selection of requirements and test procedures for a welding current measuring system 10Anne
16、x A (normative) Definition of weld times.Annex B (informative) Types of integrator and equivalent current sensing coil circuits.coils Foreword This document (EN ISO 17657-1:2007) has been prepared by Technical Committee ISO/TC 35 “Paints and varnishes” in collaboration with Technical Committee CEN/T
17、C 139 “Paints and varnishes”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by January 2008, and conflicting national standards shall be withdrawn at the la
18、test by January 2008. This document supersedes EN ISO 17657-1:2001. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia,
19、Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 17657-1:2007 has been approved by CEN as EN
20、ISO 17657-1:2007 without any modifications. 3 EN ISO 17657-1:2007 (E) Introduction Requests for official interpretations of any aspect of this part of ISO 17657 should be directed to the Secretariat of ISO/TC 44/SC 6 via your national standards body. A complete listing of these bodies can be found a
21、t http:/www.iso.org. 4 EN ISO 17657-1:2007 (E) 1 Scope This part of ISO 17657 specifies equipment for the calibration of measuring systems of welding current and indicating weld time in resistance welding using single-phase alternating current of frequency 50 Hz or 60 Hz, or direct current. The guid
22、elines define various basic terms for the measurement of welding current, and give some basic information for users of welding current measuring systems including welding current meters with current sensing coil. 2 Normative references The following referenced documents are indispensable for the app
23、lication 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. ISO 669, Resistance welding Resistance welding equipment Mechanical and electrical requirements ISO 17657-2:2005,
24、 Resistance welding Welding current measurement for resistance welding Part 2: Welding current meter with current sensing coil ISO 17657-3, Resistance welding Welding current measurement for resistance welding Part 3: Current sensing coil ISO 17657-4, Resistance welding Welding current measurement f
25、or resistance welding Part 4: Calibration system ISO 17657-5, Resistance welding Welding current measurement for resistance welding Part 5: Verification of welding current measuring system 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 669 and the f
26、ollowing apply. 3.1 test technical operation that consists of the determination of one or more characteristics or performance of a given product or equipment according to a specified procedure 5 EN ISO 17657-1:2007 (E) 3.2 verification confirmation by examination and provision of evidence that speci
27、fied requirements have been met 3.3 calibration set of operations that establish, under specified conditions, the relationship between values indicated by the measuring instrument or measuring system, and the corresponding values of a measuring instrument or measuring system with confirmed higher ac
28、curacy 3.4 welding current measuring system resistance welding measuring system that measures the welding current value and/or welding current waveform at the primary or secondary circuit of a welding transformer by using a sensing coil, non-inductive shunt or other suitable sensors 3.5 welding curr
29、ent meter resistance welding meter of portable type, or built into the weld controller for measuring short period current and which consists of at least a data capturing and calculating unit (e.g. integrator and accumulating unit) and a display unit 3.6 master welding current meter welding current m
30、eter calibrated against a reference welding current meter 3.7 reference welding current meter welding current meter which is sufficiently well-established to be used for the calibration of welding measuring systems or welding current meters 3.8 certified reference equipment reference equipment which
31、 is certified by a technically valid procedure, accompanied by, or traceable to, a certificate or other documentation issued by a certifying body 3.9 current sensing coil (toroidal coil or Rogowski coil) multi-wound coils, in which wire is wound around a non-magnetic core of constant cross section,
32、for detecting the magnetic flux generated by current 3.10 weld time time during which the welding current is applied, expressed as a number of cycles or a length of time in milliseconds NOTE Annex A gives further information on the definition of weld time. 3.11 current flow time duration defined fro
33、m the start time of current conduction to the time when its current has decreased to a 10 % level of the measured welding current value, which is applied only to direct current for determination of minimum value of the hold time NOTE 1 Annex A gives further information on the definition of current f
34、low time. NOTE 2 Current flow time is applicable only to direct current. 6 EN ISO 17657-1:2007 (E) 3.12 welding current current value accumulated over the weld time and indicated by the r.m.s. value, which is applicable for alternating and direct current NOTE 1 In the case of capacitor discharge cur
35、rent, the welding current can be indicated by the r.m.s. or the peak value. NOTE 2 Annex A in ISO 17657-2:2005 gives further information on how to calculate the welding current values. 3.13 phase control typical current control technique in resistance welding, e.g. by changing the firing angle in ea
36、ch half-weld cycle of alternating current 4 Welding current measuring system 4.1 General Welding current measuring systems consist of a welding current meter, a current sensor (e.g. current sensing coil, non-inductive shunt, or any suitable sensors) and display. 4.2 Applicability The welding current
37、 measuring system shall be selected based on a consideration of the following factors, in order to guarantee highly accurate measurement: type of current sensor (coil, shunt, other suitable sensors); type of welding current (alternating, direct or pulsed current); current level or current range; fre
38、quency of current or current waveform; location of current sensor (primary or secondary of circuit). Welding current measuring systems are classified into two types. One is used for measurement of alternating current only, which does not apply correctly to measurements of direct current. The other i
39、s a multi-purpose type applicable for the measurement of all current types, including continuous direct and pulsed direct current in addition to alternating current. 4.3 Accuracy The scatter in measured current value is caused by the following factors: manufacturing variations of current sensor and
40、existence of distortion caused by incorrect use, or excessive repeat bending in fitting and detaching the coil; setting position of current sensor; magnetic noise affecting the connection parts of cables and connecting leads; temperature variations; design differences in the integrator/amplifier use
41、d to convert the output signal of the current sensor to a current waveform, and different calculation algorithms for welding current value in the data processing 7 EN ISO 17657-1:2007 (E) unit, in particular different definitions of the start time and finish time for calculation of r.m.s. current va
42、lues; variation of the input impedance and gain setting of the integrator if the combination of the current sensor and the integrator has been changed (when using a current sensing coil). For high accurate measurements of welding current, i.e. less than 0,5 % error, the current sensing coil shall be
43、 located in the same position as that in which it was calibrated. The welding current measuring system shall be calibrated as a set including the current sensor and integrator/amplifier in order to guarantee the accuracy. If calibration of the sensor alone is required, the input impedance of the cal
44、ibration system shall be the same value as the input impedance of the welding current meter. 4.4 Welding current meter with current sensing coil The welding current sensing system consists of at least a current sensing coil, an integrator, a data processing unit, and output devices for displaying or
45、 recording the welding current value and weld time. See Figure 1. The current sensing coil is used for detecting the changing magnetic flux around the welding electrode or current conductor. The integrator converts a signal detected by the current sensing coil to the current waveform, and the data p
46、rocessing unit calculates the r.m.s. value of current over the weld time or for a fixed duration (see Annex A). Key 1 current sensing coil 5 display unit, recorder, or control devices 2 resistance welding machine 6 welding current measuring system 3 integrator 7 welding current meter 4 data processi
47、ng unit Figure 1 An example of welding current meter with current sensing coil 8 EN ISO 17657-1:2007 (E) 5 Current sensors 5.1 Type of sensor The following current sensors can be used in resistance welding: current sensing coil; non-inductive shunt; any other suitable sensors (e.g. hall devices). Th
48、e current sensing coils are predominantly used for current measurement, and classified into two main types, one is a flexible coil, the other is a rigid coil. The flexible coil type is usually used to measure the welding current set at the secondary circuit of a resistance welding machine. The rigid
49、 coil type can be mounted in any positions in the secondary or primary circuit, or built into the transformer. 5.2 Selection of current sensor The following factors shall be checked when selecting the type of a current sensor to be used: sensitivity/conversion coefficient; maximum output voltage of the current sensor in the measuring range; frequency response; setting position error; temperature dependency of the sensitivity/conversion coefficient; current sensor output load
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