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IEC TS 62153-4-1
Edition 1.0 2014-01
TECHNICAL
SPECIFICATION
colour
inside
Metallic communication cable test methods –
Part 4-1: Electromagnetic compatibility (EMC) – Introduction to electromagnetic
screening measurements
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IEC TS 62153-4-1
Edition 1.0 2014-01
TECHNICAL
SPECIFICATION
colour
inside
Metallic communication cable test methods –
Part 4-1: Electromagnetic compatibility (EMC) – Introduction to electromagnetic
screening measurements
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XD
ICS 33.100 ISBN 978-2-8322-1311-7
– 2 – TS 62153-4-1 © IEC:2014(E)
CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Symbols interpretation . 10
4 Electromagnetic phenomena. 12
5 The intrinsic screening parameters of short cables . 14
5.1 General . 14
5.2 Surface transfer impedance, Z . 14
T
5.3 Capacitive coupling admittance, Y . 14
C
5.4 Injecting with arbitrary cross-sections . 16
5.5 Reciprocity and symmetry . 16
5.6 Arbitrary load conditions . 16
6 Long cables – coupled transmission lines . 16
7 Transfer impedance of a braided wire outer conductor or screen . 24
8 Test possibilities . 30
8.1 General . 30
8.2 Measuring the transfer impedance of coaxial cables . 30
8.3 Measuring the transfer impedance of cable assemblies . 31
8.4 Measuring the transfer impedance of connectors . 31
8.5 Calculated maximum screening level . 31
9 Comparison of the frequency response of different triaxial test set-ups to measure
the transfer impedance of cable screens . 36
9.1 General . 36
9.2 Physical basics . 36
9.2.1 Triaxial set-up . 36
9.2.2 Coupling equations . 38
9.3 Simulations . 40
9.3.1 General . 40
9.3.2 Simulation of the standard and simplified methods according
to EN 50289-1-6, IEC 61196-1 (method 1 and 2) and
IEC 62153-4-3 (method A) . 40
9.3.3 Simulation of the double short circuited methods . 46
9.4 Conclusion . 54
10 Background of the shielded screening attenuation test method (IEC 62153-4-4) . 54
10.1 General . 54
10.2 Objectives . 55
10.3 Theory of the triaxial measuring method . 55
10.4 Screening attenuation . 60
10.5 Normalised screening attenuation . 62
10.6 Measured results . 63
10.7 Comparison with absorbing clamp method . 65
10.8 Practical design of the test set-up . 66
10.9 Influence of mismatches . 67
10.9.1 Mismatch in the outer circuit . 67
10.9.2 Mismatch in the inner circuit . 69
TS 62153-4-1 © IEC:2014(E) – 3 –
11 Background of the shielded screening attenuation test method for measuring the
screening effectiveness of feed-throughs and electromagnetic gaskets
(IEC 62153-4-10) . 72
11.1 General . 72
11.2 Theoretical background of the test Fixtures and their equivalent circuit . 73
11.3 Pictures and measurement results . 76
11.3.1 Characteristic impedance uniformity . 76
11.3.2 Measurements of shielding effectiveness . 78
11.3.3 Calculation of transfer impedance . 80
11.4 Calculation of screening attenuation for feed-through when the transfer
impedance Z is known . 82
T
12 Background of the shielded screening attenuation test method for measuring the
screening effectiveness of RF connectors and assemblies (IEC 62153-4-7) . 83
12.1 Physical basics . 83
12.1.1 Surface transfer impedance Z . 83
T
12.1.2 Screening attenuation a . 84
S
12.1.3 Coupling attenuation a . 84
C
12.1.4 Coupling transfer function . 84
12.1.5 Relationship between length and screening measurements . 85
12.2 Tube in tube set-up (IEC 62153-4-7) . 86
12.2.1 General . 86
12.2.2 Procedure . 86
12.2.3 Measurements and simulations . 88
12.2.4 Influence of contact resistances . 89
Bibliography . 91
Figure 1 – Total electromagnetic field . 12
(E ,H )
t t
Figure 2 – Defining and measuring screening parameters – A triaxial set-up . 13
Figure 3 – Equivalent circuit for the testing of Z . 15
T
Figure 4 – Equivalent circuit for the testing of Y = j ωC . 15
c T
Figure 5 – Electrical quantities in a set-up that is matched at both ends . 16
Figure 6 – The summing function S{L·f} for near and far end coupling . 20
Figure 7 – Transfer impedance of a typical single braid screen . 20
Figure 8 – The effect of the summing function on the coupling transfer function of a
typical single braid screen cable . 21
Figure 9 – Calculated coupling transfer functions T and T for a single braid – Z = 0 . 21
n f F
Figure 10 – Calculated coupling transfer functions T and T for a single braid – Im(Z )
n f T
is positive and Z = +0,5 × Im(Z ) at high frequencies . 22
F T
Figure 11 – Calculated coupling transfer functions T and T for a single braid – Im(Z )
n f T
is negative and Z = –0,5 × Im(Z ) at high frequencies. 23
F T
Figure 12 – : the complete length dependent factor in the coupling function T . 24
L·S
Figure 13 – Transfer impedance of typical cables . 25
Figure 14 – Magnetic coupling in the braid – Complete flux. 26
Figure 15 – Magnetic coupling in the braid – Left-hand lay contribution . 26
Figure 16 – Magnetic coupling in the braid – Right-hand lay contribution . 26
Figure 17 – Complex plane, Z = Re Z + j Im Z , frequency f as parameter . 27
T T T
Figure 18 – Magnitude (amplitude), | Z (f) | . 27
T
– 4 – TS 62153-4-1 © IEC:2014(E)
Figure 19 – Typical Z (time) step response of an overbraided and underbraided single
T
braided outer conductor of a coaxial cable . 28
Figure 20 – Z equivalent circuits of a braided wire screen . 29
T
Figure 21 – Comparison of signal levels in a generic test setup . 32
Figure 22 – Triaxial set-up for the measurement of the transfer impedance Z . 36
T
Figure 23 – Equivalent circuit of the triaxial set-up . 37
Figure 24 – Simulation of the frequency response for g . 41
Figure 25 – Simulation of the frequency response for g . 41
Figure 26 – Simulation of the frequency response for g . 42
Figure 27 – Simulation of the frequen
...