1、 IEC 60990 Edition 3.0 2016-05 REDLINE VERSION Methods of measurement of touch current and protective conductor current IEC 60990:2016-05 RLV(en) colour inside THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2016 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specified, no part of
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10、your feedback on this publication or need further assistance, please contact the Customer Service Centre: csciec.ch. IEC 60990 Edition 3.0 2016-05 REDLINE VERSION Methods of measurement of touch current and protective conductor current INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 17.220, 35.020 ISB
11、N 978-2-8322-3449-5 Registered trademark of the International Electrotechnical Commission Warning! Make sure that you obtained this publication from an authorized distributor. colour inside 2 IEC 60990:2016 RLV IEC 2016 CONTENTS FOREWORD . 6 INTRODUCTION . 8 1 Scope 11 2 Normative references . 11 3
12、Terms and definitions. 12 4 Test site 13 4.1 Test site environment 13 4.2 Test transformer . 13 4.3 Earthed neutral conductor . 13 5 Measuring equipment . 14 5.1 Selection of measuring network . 14 5.1.1 General . 14 5.1.2 Perception and startle-reaction (a.c.) 1 6 5.1.3 Letgo-immobilization (a.c.)
13、. 16 5.1.4 Electric burn (a.c.) . 16 5.1.5 Ripple-free d.c. 16 5.2 Test electrodes . 17 5.2.1 Construction 17 5.2.2 Connection 17 5.3 Configuration 17 5.4 Power connections during test . 17 5.4.1 General . 17 5.4.2 Equipment for use only on TN or TT star power distribution systems . 22 5.4.3 Equipme
14、nt for use on IT power distribution systems including unearthed delta systems . 22 5.4.4 Equipment for use on single-phase centre-earthed power supply systems or on centre-earthed delta power supply systems . 22 5.5 Supply voltage and frequency 22 5.5.1 Supply voltage . 22 5.5.2 Supply frequency . 2
15、3 6 Test procedure 23 6.1 General . 23 6.1.1 Touch current measurements . 23 6.1.2 Control switches, equipment and supply conditions 23 6.1.3 Use of measuring networks 24 6.2 Normal and fault conditions of equipment 24 6.2.1 Normal operation of equipment 24 6.2.2 Equipment and supply fault condition
16、s 24 7 Evaluation of results 26 7.1 Perception, startle-reaction and letgo-immobilization . 26 7.2 Electric burn 26 8 Measurement of protective conductor current . 26 8.1 General . 26 8.2 Multiple equipment 26 8.3 Measuring method . 27 IEC 60990:2016 RLV IEC 2016 3 Annex A (normative) Equipment . 28
17、 Annex B (normative) Use of a conductive plane 29 Annex C (normative) Incidentally connected parts . 30 Annex D (informative) Choice of current limits 31 D.1 General . 31 D.2 Limit examples 31 D.2.1 Ventricular fibrillation . 31 D.2.2 Inability to letgo-immobilization . 31 D.2.3 Startle-reaction 31
18、D.2.4 Perception threshold 31 D.2.5 Special applications . 31 D.3 Choice of limits . 32 D.4 Electric burn effects of touch current . 33 Annex E (informative) Networks for use in measurement of touch current . 34 E.1 General . 34 E.2 Body impedance network Figure 3 34 E.3 Perception, Startle-reaction
19、 (and body impedance) network Figure 4 . 34 E.4 Letgo-immobilization (and body impedance) network Figure 5 . 35 Annex F (informative) Measuring network limitations and construction 36 Annex G (informative) Construction and application of touch current measuring instruments . 38 G.1 Considerations fo
20、r selection of components . 38 G.1.1 General . 38 G.1.2 Power rating and inductance for R S and R B38 G.1.3 Capacitor C S38 G.1.4 Resistors R1, R2 and R3 39 G.1.5 Capacitors C1, C2 and C3 39 G.2 Voltmeter 39 G.3 Accuracy . 39 G.4 Calibration and application of measuring instruments . 40 G.5 Records
21、40 G.6 Confirmation systems 41 Annex H (informative) Grippable part . Annex H (informative) Analysis of frequency filtered touch current circuit measurements 44 Annex I (informative) AC power distribution systems (see 5.4) 52 I.1 Introduction General 52 I.2 TN power systems . 53 I.3 TT power systems
22、 . 56 I.4 IT power systems 57 Annex J (informative) Routine and periodic touch current tests, and tests after repair or modification of mains operated equipment . 59 Annex K (normative) Network performance and calibration . 60 K.1 Network or instrument performance and initial calibration 60 K.2 Cali
23、bration in a confirmation system 62 K.2.1 General . 62 K.2.2 Measurement of input resistance 62 K.2.3 Measurement of instrument performance . 62 4 IEC 60990:2016 RLV IEC 2016 Annex M (informative) Bibliography . 65 Figure 1 Example of earthed neutral, direct supply 14 Figure 2 Example of earthed neu
24、tral, with transformer for isolation . 14 Figure 3 Measuring network, unweighted touch current . 15 Figure 4 Measuring network, touch current weighted for perception or startle-reaction 15 Figure 5 Measuring network, touch current weighted for letgo-immobilization 16 Figure 6 Test configuration: Sin
25、gle-phase equipment on star TN or TT system . 18 Figure 7 Test configuration: Single-phase equipment on centre-earthed TN or TT system 18 Figure 8 Test configuration: Single-phase equipment connected line-to-line on star TN or TT system . 19 Figure 9 Test configuration: Single-phase equipment connec
26、ted line-to-neutral on star IT system 19 Figure 10 Test configuration: Single-phase equipment connected line-to-line on star IT system 20 Figure 11 Test configuration: Three-phase equipment on star TN or TT system 20 Figure 12 Test configuration: Three-phase equipment on star IT system . 21 Figure 1
27、3 Test configuration: Unearthed delta system . 21 Figure 14 Test configuration: Three-phase equipment on centre-earthed delta system 22 Figure A.1 Equipment . 28 Figure B.1 Equipment platform . 29 Figure F.1 Frequency factor for electric burn 36 Figure F.2 Frequency factor for perception or startle-
28、reaction . 37 Figure F.3 Frequency factor for letgo-immobilization . 37 Figure H.1 Grippable part test device Figure H.1 Triangular waveform touch current, startle-reaction . 45 Figure H.3 1 ms rise time pulse response, startle-reaction 46 Figure H.4 1 ms rise time pulse response, letgo-immobilizati
29、on . 46 Figure H.5 Touch current vs. rise time plot, 20 ms square wave 47 Figure H.6 PFC SMPS touch current waveform . 47 Figure H.7 50 Hz square wave, 0,1 ms rise time, startle-reaction 48 Figure H.8 50 Hz square wave, 0,1 ms rise time, letgo-immobilization . 48 Figure H.9 IEC TS 60479-2 let-go thr
30、eshold for AC and DC combinations augmented by additional data, mA each axis . 49 Figure H.10 Ex1 case: showing r.m.s. window 50 Figure H.11 Waveform ex2 case: showing r.m.s. window 50 Figure I.1 Examples of TN-S power system 54 Figure I.2 Example of TN-C-S power system. 55 Figure I.3 Example of TN-
31、C power system 55 Figure I.4 Example of single-phase, 3-wire TN-C power system 56 Figure I.5 Example of 3-line and neutral TT power system 56 Figure I.6 Example of 3-line TT power system 57 Figure I.7 Example of 3-line (and neutral) IT power system . 57 IEC 60990:2016 RLV IEC 2016 5 Figure I.8 Examp
32、le of 3-line IT power system 58 Table H.1 Triangular waveform response comparison . 45 Table H.2 Square wave touch current response 46 Table H.3 Square wave monopolar touch current response . 48 Table H.4 Mixed ACnDC waveform evaluation, ex1 . 50 Table H.5 Mixed ACnDC waveform evaluation, ex2 . 51 T
33、able K.1 Calculated input impedance and transfer impedance for unweighted touch current measuring network (Figure 3) 60 Table K.2 Calculated input impedance and transfer impedance for perception or startle-reaction touch current measuring network (Figure 4) . 61 Table K.3 Calculated input impedance
34、and transfer impedance for letgo- immobilization current measuring network (Figure 5) . 61 Table K.4 Output voltage to input voltage ratios for unweighted touch current measuring network (Figure 3) 63 Table K.5 Output voltage to input voltage ratios for startle-reaction measuring network (Figure 4)
35、63 Table K.6 Output voltage to input voltage ratios for letgo-immobilization measuring network (Figure 5) . 64 6 IEC 60990:2016 RLV IEC 2016 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ METHODS OF MEASUREMENT OF TOUCH CURRENT AND PROTECTIVE CONDUCTOR CURRENT FOREWORD 1) The International Electrotechn
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48、Additions are in green text, deletions are in strikethrough red text. IEC 60990:2016 RLV IEC 2016 7 International Standard IEC 60990 has been prepared by TC 108: Safety of electronic equipment within the field of audio/video, information technology and communication technology. This third edition ca
49、ncels and replaces the second edition published in 1999. It constitutes a technical revision. The principal changes in this edition as compared with the second edition are as follows: the effects names have been updated to reflect increased understanding of the range of effects and is in concert with present usage; the conditions of use invoking a GRIPPABLE PART have been reduced in the application of the requirements based upon
