1、BRITISH STANDARD BS EN 60512-23-7:2005 Connectors for electronic equipment Tests and measurements Part 23-7: Screening and filtering tests Test 23g: Effective transfer impedance of connectors The European Standard EN 60512-23-7:2005 has the status of a British Standard ICS 31.220.10 BS EN 60512-23-7
2、:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 18 April 2005 BSI 18 April 2005 ISBN 0 580 45821 0 National foreword This British Standard is the official English language version of EN 60512-23-7:2005. It is identical with IEC 60512-23
3、-7:2005. The UK participation in its preparation was entrusted by Technical Committee EPL/48, Electromechanical components, to Subcommittee EPL/48/2, Connectors for electronic equipment, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on requ
4、est to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI E
5、lectronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers
6、to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document
7、comprises a front cover, an inside front cover, the EN title page, pages 2 to 16, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 605
8、12-23-7 NORME EUROPENNE EUROPISCHE NORM March 2005 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 2005 CENELEC - All rights of
9、exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60512-23-7:2005 E ICS 31.220.10 English version Connectors for electronic equipment Tests and measurements Part 23-7: Screening and filtering tests Test 23g: Effective transfer impedance of connectors (IEC
10、60512-23-7:2005) Connecteurs pour quipements lectroniques Essais et mesures Partie 23-7: Essais dcrantage et de filtrage Essai 23g: Impdance de transfert efficace des connecteurs (CEI 60512-23-7:2005) Steckverbinder fr elektronische Einrichtungen Mess- und Prfverfahren Teil 23-7: Prfungen der Schirm
11、ung und Dmpfung Prfung 23g: Effektive Transferimpedanz von Steckverbindern (IEC 60512-23-7:2005) This European Standard was approved by CENELEC on 2005-03-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standar
12、d 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 Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French
13、, German). A version in any other language made by translation under the responsibility of a CENELEC member 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, Cy
14、prus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Foreword The text of document 48B/1505/FDIS, fut
15、ure edition 1 of IEC 60512-23-7, prepared by SC 48B, Connectors, of IEC TC 48, Electromechanical components and mechanical structures for electronic equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60512-23-7 on 2005-03-01. The following dates were fixed: l
16、atest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2005-12-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2008-03-01 Annex ZA has been added by CENELEC. _ Endor
17、sement notice The text of the International Standard IEC 60512-23-7:2005 approved by CENELEC as a European Standard without any modification. _ Page2 EN60512237:2005 CONTENTS 1 Scope and object4 2 Normative references .4 3 Terms and definitions .5 4 Preparation 7 4.1 Test set-up7 4.2 Resources.8 4.3
18、 Preparation of the specimen and the calibrator 9 5 Method.10 5.1 Conditioning10 5.2 Impedance regularity.10 5.3 Operational attenuation of the connecting cables and the DUT.10 5.4 Procedure .10 6 Evaluation of the effective transfer impedance11 7 Details to be specified 12 8 Documentation .12 Annex
19、 A (informative) Screening attenuation calculation .13 A.1 Objective13 A.2 Definition of screening attenuation of a connector screen13 A.3 Screening attenuation A SCin dB.13 Annex B (informative) Test set-up verification .14 B.1 Objective14 B.2 Test set-up verification .14 Page3 EN60512237:2005 CONN
20、ECTORS FOR ELECTRONIC EQUIPMENT TESTS AND MEASUREMENTS Part 23-7: Screening and filtering tests Test 23g: Effective transfer impedance of connectors 1 Scope and object This part of IEC 60512-23 defines a test method which is intended to assess the screening effectiveness of screened non-circular mul
21、ti-pole, electrically short, connectors by the measurement of the effective (surface) transfer impedance Z TE expressed in , using a network analyzer, for frequencies up to 1 GHz. It is based on the line injection test method according IEC 61196-1 with a specific type of injection wire, which is ada
22、pted to the shapes of connectors. Due to the specific test set-up used in the method described hereinafter the connector screen itself is not verified, but the combination of two connectors (male and female) together, i.e. the test results include the effectiveness of the screens of the two connecto
23、rs and the joint between the connectors and the joints of the cable to the connector. 2 Normative references 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
24、the referenced document (including any amendments) applies. IEC 60050(581), International Electrotechnical Vocabulary (IEV) Chapter 581: Electro- mechanical components for electronic equipment IEC 60068-1:1988, Test requirements Part 1: General requirements and guidance IEC 60512-1-100: Electromecha
25、nical components for electronic equipment Basic testing procedures and measuring methods Part 1-100: General Applicable publications IEC 60512-23-3: Electromechanical components for electronic equipment Basic testing procedures and measuring methods Part 23-3: Screening and filtering tests Test 23c:
26、 Screening effectiveness of connectors and accessories IEC 61196-1:1995, Radiofrequency cables Part 1: Generic specification General, definitions, requirements and test methods Page4 EN60512237:2005 3 Terms and definitions For the purposes of this document, the terms and definitions of IEC 60050(581
27、) and the following additional definitions apply. 3.1 inner and outer circuit inner circuit consists of the screens and the conductor of the test specimen. The inner circuit measured or calculated quantities may be identified in the equations and figures by the symbols with the subscript 1, for exam
28、ple: U 1 , Z 1 , or I 1 . Outer circuit, which consist of the screen surface and the inner surface of a surrounding test jig box. The outer circuit measured or calculated quantities may be identified in the equations and figures by the symbols with the subscript 2, for example: U 2 , Z 2 , or I 2 .
29、3.2 transfer impedance Z Tquotient of the longitudinal voltage induced in the outer circuit formed by the screen under test and the measuring box and the current fed into the inner circuit or vice versa. Z Tof the connector is expressed in ohms ( ) or decibels (dB) in relation to 1 U 2n= U 2 2 Z 2 Z
30、 T U 2f= U 2 2 Z 2 Z 2 Z 1 U 1 E Z 1 U 1 I 1n I 1f l /101 2 T I U Z = Expression in dB ( ): + = 1 log 20 ) ( dB T 10 T Z Z Figure 1 Definition of Z T 3.3 capacitive coupling impedance Z Fquotient of twice the voltage induced to the terminating impedances Z 2of the matched outer circuit by a current
31、I 1fed (without retouring over the screen) to the far-end termination Z 1of the inner circuit or vice versa (in dB, see 3.2) IEC 138/05 Page5 EN60512237:2005 U 1f U 1n Z 2 I 2n U 2n Z 2 I 2 C T I 2f Z 2 I 1 Z 1 I 1 Z 1 U 1 l /10 U 2f I 1I 2n = I 2fU 1n = U 1fI 2n = I 2f= (1/2) I 2 = I 2 /2I 2 = I 2n
32、 + I 2fT 2 1 1 f 2 1 f 2 n 2 f 2 C j Z Z I U I U U Z = = + =Expression in dB ( ): + = 1 log 20 ) ( dB F 10 F Z Z Figure 2 Definition of Z F 3.4 effective transfer impedance Z TEmaximum absolute value of the sum or difference of the Z F and Z Tat every frequency T F TE max Z Z Z = Expression en dB (
33、): + = 1 log 20 ) ( dB TE 10 TE Z Z 3.5 coupling length combined length of the two connectors and cables, which are inside the test jig is called the coupling length L c . The highest frequency f maxto which Z T , Z Fand Z TEcan be measured is dependant on the coupling length. The maximum frequency
34、f maxis different when measuring from the near- or far-end. The f maxshould be kept under the corner frequency f cof the summing function. r2 r1 c c, f n = L c f IEC 139/05 Page6 EN60512237:2005 The maximum coupling lengh max c, L allowed on the highest frequencies f n max f is r2 r1 max c, max c, f
35、 n f n = f c L where max c, L is the maximum coupling length (m); max f is the highest frequency (Hz); c is the velocity of light 300 Mm/s; r1 is the resulting relative permittivity of the dielectric of the connector and the connecting cable for the length L c(inner system); r2 is the resulting rela
36、tive permittivity of the dielectric of the outer system. NOTE The condition means that the phase constant of the cable multiplied with the length is less than 1. 4 Preparation 4.1 Test set-up Network analyzer Generator Receiver Coax switch n f LF toroid ferrite Adapter Screened 50 resistor DUT (Devi
37、ce under test) Test jig outer screen HF toroid ferrite Cable assemblyFigure 3 Example of a practical measurement set-up IEC 140/05 Page7 EN60512237:2005 P 1n P 0 P 1f Z 1 Z 1Figure 5 Schematic measurement circuit 4.2 Resources The measurements shall be performed using a network analyzer or alternati
38、vely, a discrete signal generator and selective measuring receiver. The measuring equipment consists of a) a network analyzer with a sufficient frequency range or alternatively, a signal generator with the same characteristic impedance as the quasi-coaxial system of the cable under test or with an i
39、mpedance adapter and complemented with a power amplifier and/or a low noise amplifier if necessary for very low transfer impedance (The noise floor of the test set-up shall be 10 dB lower than the measurement.); b) a time domain reflectometer (TDR) with a system rise time of less than 200 ps or a 5
40、GHz network analyzer with FD/TD facilities; c) two adapters, see Figure 4; the included impedance matching network, needed to match the near- and far-end of the inner circuit to the receiver, is calculated as follows: If the impedance of the inner system Z 1is less than 50 (the receiver input resist
41、ance) the formulas below are used. 50 1 . 50 1 s Z R = 50 1 1 1 p Z Z R = The configuration is depicted below: R s 50 side R p Z 1sideIEC 142/05 IEC 143/05 Page8 EN60512237:2005 The voltage gain, k mof the circuit is: Going from the receiver (50 ) to the DUT (Z 1 ) s 1 p p 1 p 1 RD m, R Z R R R Z R
42、Z k s + + = Going from the DUT (Z 1 ) to the receiver (50 ) + = 50 50 s DR m, R k If the impedance of the inner system Z 1is greater than 50 (the receiver input resistance) the formulae below are used. 1 1 s 50 1 Z Z R = 1 p 50 1 50 Z R = The configuration is depicted below: R s 50 side R p Z 1sideT
43、he voltage gain, k mof the circuit is: Going from the receiver (50 ) to the DUT (Z 1 ) 1 s 1 RD m, Z R Z k + = Going from the DUT (Z 1 ) to the receiver (50 ) s s p p p DR m, 50 50 50 R R R R R k + + = d) a test jig, being a fully screened enclosure of which both halves (for easy access) shall be jo
44、ined by using metal finger-strips; the size of the jig shall be such to contain the DUT and one of the adapters; e) clip-on toroid ferrites (It is recommended to supply all the test leads of the measurement cable assemblies with these ferrites); f) a 1-2 port coaxial switch. 4.3 Preparation of the s
45、pecimen and the calibrator For the preparation of the specimen, the following details shall apply, according to the detail specification: a) preparation of the connector (DUT) and the necessary cable assembly; b) adapters, matched between the measuring equipment (50 ) and the impedance of the connec
46、tor contacts in parallel, and thus the conductors of the screened cable in parallel, see Figure 4; IEC 144/05 Page9 EN60512237:2005 c) applying the clip-on ferrites, they will be reinforced at lower frequencies by taking a number of turns of the test circuit coaxial cables through the ferrite toroid
47、s. 5 Method 5.1 Conditioning The test is performed under standard atmospheric conditions in accordance with IEC 60068-1. No temperature correction is needed. 5.2 Impedance regularity The impedance regularity of the outer and inner circuit should be tested in the frequency and time domain (system ris
48、e time of the step function measurement below 200 ps (TDR) or 5 GHz bandwidth of a Network Analyzer to be able to be distinguished between the reflection points in the conversion frequency domain/time domain) where the time domain measurement is used to detect impedance steps in the set-up. The return loss (frequency domain) in the outer and inner test circuit should be 10 dB less in magnitude than the screening effectiveness values, over the frequency range in which the measurements are taken. 5.3 Operational attenuation o
