1、September 2007DEUTSCHE NORM English price group 13No 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、12www.din.deDDIN EN ISO 17657-4Resistance welding Welding current measurement for resistance welding Part 4: Calibration system (ISO 17657-4:2005)English version of DIN EN ISO 17657-4:2007-09Widerstandsschweien Schweistrommessung fr das Widerstandsschweien Teil 4: Kalibriersystem (ISO 17657-4:2005)E
3、nglische Fassung DIN EN ISO 17657-4:2007-09SupersedesDIN ISO 17657-4:2006-02www.beuth.deDocument comprises 30 pages 11.07DIN EN ISO 17657-4:2007-09 2 National foreword This standard has been prepared by Technical Committee ISO/TC 44 “Welding and allied processes”, Subcommittee SC 6 “Resistance weldi
4、ng” (Secretariat: DIN, Germany) and has been adopted as EN ISO 17657-4:2007 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 Widerstandsschweien (D
5、VS 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: Calibration sys
6、tem 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 17657-4:2006-02 as follows: a) The text of ISO 17657-4 has been adopted by
7、CEN without any modification. Previous editions DIN ISO 17657-4: 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 17657-4 June 2007 ICS 25.
8、160.10 English Version Resistance welding - Welding current measurement for resistance welding - Part 4: Calibration system (ISO 17657-4:2005) Soudage par rsistance - Mesurage des courants en soudage par rsistance - Partie 4: Systme dtalonnage (ISO 17657-4:2005) Widerstandsschweien - Schweistrommess
9、ung fr das Widerstandsschweien - Teil 4: Kalibriersystem (ISO 17657-4:2005) 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 giving this European Standard the status of a national s
10、tandard 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 versions (English, French, German). A version in any ot
11、her 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, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estoni
12、a, 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 STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPI
13、SCHES 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 17657-4:2007: EContents Page 2 EN ISO 17657-4:2007 (E) Foreword. 3 Introduction 4 1 Scope .5 2
14、 Normative references .5 3 Terms and definitions. 5 4 Construction of calibration system 6 4.1 Reference welding current measuring system 6 4.2 Test set-up .6 4.3 Basic feature for calibration of welding current measuring system 6 4.4 Basic feature for calibration of current sensor .8 4.5 Basic feat
15、ure for calibration of welding current meter without sensor .9 5 Physical environment and operating conditions 10 6 Calibration requirements .10 6.1 Reference welding current measuring system 10 6.2 Reference current sensor.10 6.3 Data acquisition device 11 6.4 Test stage and power sources 11 7 Test
16、 report .11 7.1 Test report for calibration of welding current measuring systems .11 7.2 Test report for calibration of current sensors .12 7.3 Test report for calibration of welding current meters without sensors. .12 8 Test procedure 13 8.1 General .13 8.2 Calibration of welding current measuring
17、system . 13 8.3 Calibration of current sensor 14 8.4 Calibration of welding current meter without sensor 14 8.5 Special calibration cases .14 Annex A (informative) Measuring set-up16 Annex B (informative) Items to be recorded or filed as reference documentation for calibration 21 Annex C (informativ
18、e) Examples of the test report in accordance with this part of ISO 17657 .23 Foreword The text of ISO 17657-4:2005 has been prepared by Technical Committee ISO/TC 44 “Welding and allied processes” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 17657-4:2
19、007 by Technical Committee CEN/TC 121 “Welding”, 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 December 2007, and conflicting national standards shall be
20、 withdrawn at the latest by December 2007. 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, Finland, France, Germany,
21、 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 17657-4:2005 has been approved by CEN as EN ISO 17657-4:2007 without
22、any modifications. 3 EN ISO 17657-4:2007 (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 at http:/www.iso.org. 4 EN
23、 ISO 17657-4:2007 (E) 1 Scope This part of ISO 17657 specifies calibration systems and calibration procedures for welding current measuring systems, current sensors, welding current meters and monitoring devices with current sensor used for measuring welding current in resistance welding with altern
24、ating current of 50 Hz or 60 Hz, or with direct current. The procedures are applicable for a current range between 0,5 kA and 25 kA. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies.
25、 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, Resistance welding Welding current measurement for resistance welding Part 2: Weldin
26、g current meter with current sensing coil ISO 17657-3:2005, Resistance welding Welding current measurement for resistance welding Part 3: Current sensing coil 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 669 and the following apply. 3.1 test (curr
27、ent) sensor current sensor to be calibrated 3.2 reference (current) sensor current sensor calibrated in highly accurate condition, used for calibration of current sensors 3.3 test welding current meter welding current meter to be calibrated 5 EN ISO 17657-4:2007 (E) 3.4 non-inductive shunt high prec
28、ision and low value resistance with a very low inductive component 3.5 analog-to-digital converter ADC device to convert analog input signals into digital signals 3.6 data acquisition device instrument or device used to acquire analog data, which tracks changes in physical variables such as voltage,
29、 current and temperature 3.7 measuring accuracy of reference welding current measuring system sum of measuring accuracy values of each component calibrated by a certified reference equipment (e.g. reference sensor, integrator, ADC etc.) 4 Construction of calibration system 4.1 Reference welding curr
30、ent measuring system Components of a reference welding current measuring system shall be calibrated by certified reference equipment in accordance with Clause 6. The reference welding current measuring system consists of a calibrated current sensor, a data acquisition system and a display unit or a
31、recorder. 4.2 Test set-up The test set-up consists of a test stage or an appropriate circuit for conducting high current, and a power source with a current control unit for supplying a test current. All signal cables shall be twisted and shielded. The cable resistance shall be very small and negligi
32、ble compared to the impedance of the current sensor. Typical examples of the test set-up are shown in Annex A. NOTE A resistance welding machine/transformer can be used as a test set-up. 4.3 Basic feature for calibration of welding current measuring system A welding current meter with a current sens
33、or should be calibrated in a set consisting of the meter and the sensor. Calibration systems for a welding current meter with its sensor consist of a test set-up, a reference welding current measuring system and the welding current measuring system to be tested. The function of a reference welding c
34、urrent meter can be replaced with a calibrated data acquisition device. Figure 1 shows the basic features required for calibration of welding current measuring system. 6 EN ISO 17657-4:2007 (E) a) b) Key 1 reference welding current measuring system 2 reference sensor 3 test sensor 4 alternating curr
35、ent or direct current power source 5 secondary circuit 6 test welding current meter 7 reference welding current meter 8 test set-up 9 data acquisition device Figure 1 Basic feature for calibration of welding current measuring system 7 EN ISO 17657-4:2007 (E) 4.4 Basic feature for calibration of curr
36、ent sensor A calibration system for a current sensor consists of a test set-up, a reference welding current measuring system and a calibrated data acquisition device connected to the current sensor to be tested. The function of the reference welding current meter can be replaced by using another cha
37、nnel of the data acquisition device. Figure 2 shows the basic feature required for the calibration of current sensor. a) b) Key 1 reference welding current measuring system 2 reference sensor 3 test sensor 4 alternating current power source 5 secondary circuit 6 data acquisition device 7 reference w
38、elding current meter 8 data acquisition device Figure 2 Basic feature for the calibration of current sensor 8 EN ISO 17657-4:2007 (E) 4.5 Basic feature for calibration of welding current meter without sensor A calibration system for a welding current meter of the high-impedance integrator type witho
39、ut current sensor consists of a calibrated data acquisition device of the high-input-impedance integrator type, a calibrated reference sensor, and the test welding current meter. See Figure 3 a). The welding current meter to be tested is connected to the same output port of the reference current sen
40、sor. The data acquisition device shall not be replaced by a reference welding current meter of the low-impedance integrator type. For calibration of a welding current meter with the low impedance integrator unit, and when two reference coils are used for the calibration, the calibration system shall
41、 consist of a calibrated reference welding current measuring system and a calibrated second reference sensor connected to the welding current meter to be tested. See Figure 3 b). a) b) Key 1 reference welding current measuring system 2 reference sensor 3 second reference sensor 4 alternating current
42、 or direct current power source 5 secondary circuit 6 test welding current meter 7 reference welding current meter 8 data acquisition device Figure 3 Basic feature for calibration of welding current meter without sensor 9 EN ISO 17657-4:2007 (E) 5 Physical environment and operating conditions Unless
43、 otherwise specified, the calibration system shall be capable of operating under the following conditions without any adverse effect on its accuracy. Any deviation from these conditions shall be agreed upon between the test laboratory and the client. at an ambient air temperature between +5 C and +4
44、0 C; in relative humidity up to 95 %; at altitudes up to 1 000 m above mean sea level. 6 Calibration requirements 6.1 Reference welding current measuring system Components of the reference welding current measuring system shall be calibrated by using certified reference equipment at least once a yea
45、r. The total measuring accuracy is defined as the sum of measuring accuracy of each component of the reference welding current measuring system and shall be better than that stipulated for the highly accurate class stipulated in ISO 17657-2. The specification, name of certifying test body and releva
46、nt data for the reference welding current measuring system, including the data acquisition device, and the reference current sensor shall be recorded on all documentation. See Annex B. 6.2 Reference current sensor Properties of reference current sensor shall be measured accurately with no external i
47、nfluences (e.g. strong magnetic field caused by the high current) and calibrated by using certified reference equipment at a full wave alternating current of 50 Hz or 60 Hz, or direct current. In the case of using a non-inductive shunt as the reference current sensor, the conversion coefficient shal
48、l be between 10 mV/kA and 150 mV/kA, and the error shall be less than 0,25 %. The phase shift between a measured welding current and the output voltage shall be less than 1 for a sinusoidal wave current of 10 kHz. Measuring accuracy of the reference current sensor including positioning error shall b
49、e within 0,5 %, or the position should be fixed with pre-mounted current sensors on the current conductor to prevent any positioning error. NOTE A current sensing coil used as a reference current sensor should be made with as low internal impedance as possible. Recommended specifications for a current sensing coil to be cased as a reference current sensor are shown below: toroidal coil with return winding known as a Rogowski-type coil; L 23 EN ISO 17657-4:2007 (E) C.2 Test report for calibration of a current sen
