GB/T 31723.405-2026Metallic communication cable test methods - Part 4-5: Electromagnetic compatibility (EMC) - Screening or coupling attenuation - Absorbing clamp method (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting.

This document is Parts 4-5 of GB/T 31723.GB/T 31723 has already published the following parts.

---Parts 4-5.Electromagnetic Compatibility Coupling or Shielding Attenuation Absorption Clamp Method;

---Parts 4-6.Electromagnetic Compatibility Surface Transfer Impedance Line Injection Method;

---Part 4-11.Electromagnetic Compatibility Patch Cords, Coaxial Cable Assemblies, Connectors, and Cable Coupling Attenuation or Shielding Attenuation Absorption Pliers;

---Part 4-12.Coupling attenuation or shielding attenuation absorption clamp method for electromagnetic compatibility connection hardware;

---Part 4-13.Coupling Attenuation Absorption Clamp Method for Electromagnetic Compatibility Links and Channels (Laboratory Conditions);

---Part 4-14.Coupling attenuation absorption clamp method for electromagnetic compatibility cable assemblies (field conditions).

This document replaces GB/T 31723.405-2015 "Test Methods for Metallic Communication Cables - Part 4-5.Electromagnetic Compatibility Shielding or Coupling".

Compared with GB/T 31723.405-2015, the main technical changes in the "Combined Attenuation Absorption Clamp Method" are as follows, apart from structural adjustments and editorial modifications.

as follows.

---The measurement frequency has been changed, with the upper limit extended to 2400MHz (see Chapter 1, 2015 edition);

---The term "quasi-coaxial cable" has been added (see 3.1);

---Added "Performance Characteristics of Balanced-Unbalanced Converters (30MHz~2400MHz)" (see Table 2);

---Added "TP Connection Unit Requirements" (see 5.3);

---Added "Mismatch Conditions" (see 7.2.2);

---Added "Arrangement for Coupling Attenuation Measurement of Unbalanced-to-Unbalanced Converters" and "Representation of Test Results" (see 7.3.2 and).

7.3.3);

---A normative appendix, "Determination of Internal Circuit Impedance," has been added (see Appendix A).

This document is equivalent to IEC 62153-4-5:2021 "Metallic communication cables - Test methods - Part 4-5.Electromagnetic compatibility - Shielding or coupling".

"Combined attenuation absorption clamp method".

The following minimal editorial changes have been made to this document.

---Added the definitions of parameters Pdiff and Pcom,max in Chapter 4, which are respectively "matching differential mode power" and "matching common mode maximum power".

Peak value;

---Adjust Figures 2 and 3 to be included in section 5.1 to maintain consistency with the content of section 5.1;

---The definition of alphaTP-connectingunit in formula (6) has been added as "the attenuation of the TP connection unit used";

---Correct the numerator "P2" to "P1" in formulas (7), (8), (10), and (11);

---Correct the third row and fourth column of the left-hand matrix in formula (E.2) to "S34";

---Correct "SxyAB" in formula (E.3) to "SxyAB" to be consistent with Figure E.4.

Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents.

This document was proposed by the Ministry of Industry and Information Technology of the People's Republic of China.

This document is under the jurisdiction of the National Technical Committee on Standardization of High-Frequency Cables and Connectors for Electronic Equipment (SAC/TC190).

Introduction

To standardize electromagnetic compatibility measurements of metal communication cables, patch cords, and coaxial cable assemblies, and to provide a basis for the measurement of electromagnetic compatibility of metal communication cables, patch cords, and coaxial cables.

Component manufacturers and testing organizations offer various electromagnetic compatibility (EMC) measurement methods. GB/T 31723 specifies the EMC measurement methods for metallic communication cables.

Definition of measurement, limits, and test procedures and requirements for different measurement methods.

GB/T 31723 is proposed to consist of the following parts.

---Part 4-0.Recommended limits for the relationship between electromagnetic compatibility surface transfer impedance and shielding attenuation. The aim is to establish...

This relates to the relationship and recommended limits between surface transfer impedance and shielding attenuation in communication cables.

---Part 4-1.Introduction to Electromagnetic Compatibility Shielding Measurement. The purpose is to establish a measurement and testing method for the electromagnetic shielding of metallic communication cables.

General specifications for site, equipment, procedures and data processing.

---Part 4-2.Electromagnetic Compatibility Shielding and Coupling Attenuation Injection Clamp Method. The aim is to establish the shielding attenuation of metallic communication cables.

And an injection clamp test method for dynamic coupling attenuation of balanced shielded or unshielded data cables.

---Part 4-3.Electromagnetic Compatibility Surface Transfer Impedance Triaxial Method. The aim is to establish the surface transfer impedance of metallic communication cables.

A method for testing the resistance of three coaxial axes.

---Part 4-4.Electromagnetic Compatibility Shielding Attenuation Test Method for Shielding Attenuation alphaS at Frequencies 3GHz and Above (Triaxial Method).

The key is to establish a three-coaxial test method for shield attenuation of metal communication cables.

---Parts 4-5.Electromagnetic Compatibility Coupling or Shielding Attenuation Absorption Clamp Method. The purpose is to establish the coupling or shielding of metallic communication cables.

Absorption clamp test method for masking attenuation.

---Parts 4-6.Electromagnetic Compatibility Surface Transfer Impedance Line Injection Method. The purpose is to establish the surface transfer impedance of metallic communication cables.

Anti-line injection test method.

---Parts 4-7.Test Procedures for Transfer Impedance ZT and Shielding Attenuation alphaS or Coupling Attenuation alphaC of Electromagnetic Compatibility Connectors and Components Method 3.Coaxial Tube-in-Tube Test. The purpose is to establish the tube-in-tube test for impedance transfer, coupling, or shielding attenuation in metallic communication cables.

method.

---Parts 4-8.Electromagnetic Compatibility Capacitive Coupling Admittance. The purpose is to establish the capacitive coupling admittance of metallic cables and other passive components.

The testing method for nano.

---Parts 4-9.Coupling Attenuation Triaxial Method for Electromagnetic Compatibility Shielded Balanced Cables. The aim is to establish the coupling attenuation method for shielded balanced cables.

A three-coaxial test method for coupling attenuation.

---Part 4-10.Electromagnetic Compatibility Feedthrough and Electromagnetic Pad Transfer Impedance and Shielding Attenuation Dual-Coaxial Method. The aim is to establish...

A dual coaxial test method for the transfer impedance and shielding attenuation of feedthrough devices and electromagnetic pads.

---Part 4-11.Electromagnetic Compatibility Patch Cords, Coaxial Cable Assemblies, Connector Cables, Coupling Attenuation or Shielding Attenuation Absorption Clamps the purpose of this method is to establish the absorption clamp test for cable coupling attenuation or shielding attenuation in patch cords, coaxial cable assemblies, and connectors.

method.

---Part 4-12.Coupling attenuation or shielding attenuation absorption clamp method for electromagnetic compatibility (EMC) connection hardware. The purpose is to establish the connection hardware...

Absorption clamp test method for component coupling attenuation or shielding attenuation.

---Part 4-13.Coupling Attenuation of Electromagnetic Compatibility Links and Channels (Laboratory Conditions) Absorption Clamp Method. The aim is to establish experimental...

Absorption clamp test method for link and channel coupling attenuation under indoor conditions.

---Part 4-14.Coupling Attenuation of Electromagnetic Compatibility Cable Assemblies (Field Conditions) Absorption Clamp Method. The purpose is to establish field conditions.

Absorption clamp test method for coupling attenuation of cable assemblies.

---Part 4-15.Electromagnetic Compatibility Test Methods for Measuring Transfer Impedance and Shielding Attenuation or Coupling Attenuation Using Triaxial Elements.

The purpose is to establish a triaxial test unit to measure the transfer impedance, shielding attenuation, or coupling attenuation of metallic communication cables and other passive components.

The test method for reduction.

---Part 4-16.Electromagnetic Compatibility Using a triaxial arrangement to extend the measurement frequency range of transfer impedance to higher frequencies and to shield the frequency range for attenuation measurements has been extended to lower frequencies. The aim is to establish the metal communication when using a specific triaxial apparatus for measurement.

Extrapolating test results of impedance transfer of passive components such as cables to higher frequencies, and extrapolating test results of shielding attenuation to lower frequencies.

The method.

---Part 4-17.Electromagnetic Compatibility Reduction Factor. The purpose is to establish a test method for the reduction factor of metallic communication cables.

Test methods for metallic communication cables, Parts 4-5.

Electromagnetic compatibility shielding or coupling attenuation absorption clamp method

1 Scope

This document describes the determination of metals within the frequency range of 30MHz to 1000MHz (2400MHz) (depending on the performance of the absorption clamp).

Absorption clamp method for the coupling or shielding attenuation characteristics of communication cables. This method is based on the three-stage absorption clamp method specified in IEC 62153-4-4 or IEC 62153-4-9.

An alternative to the coaxial method. Because the external circuitry for the absorption clamp method is not specified, test results obtained in different locations and laboratories may vary.

The difference is significant, and the variation can even exceed ±6dB.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

Note. GB/T 14733.2-2008 Telecommunications Terminology - Transmission Lines and Waveguides (IEC 60050-726:1982, IDT) IEC TS62153-4-1 Test methods for metallic communication cables – Part 4-1.Introduction to electromagnetic compatibility and electromagnetic shielding measurements [Me-CISPR 16-1-3.2004 Specification for apparatus and methods of measuring radio disturbances and immunity – Part 1-3.Radio disturbances and immunity equipment-Disturbancepower) Note. GB/T 6113.103-2021 Specification for Radio Interference and Immunity Measurement Equipment and Methods Part 1-3.Radio Interference and Immunity Measurement Interference power of auxiliary equipment in measurement equipment (CISPR16-1-3.2016, IDT)

3 Terms and Definitions

The terms and definitions defined in IEC 60050-726 and IEC TS62153-4-1, as well as the following terms and definitions, apply to this document.

The URLs for the terminology databases maintained by ISO and IEC for standardization are as follows.

quasi-coaxial cable

A cable structure having two or more inner conductors, enclosed by a cable shield that serves as an outer conductor, and connected together at both ends.

Note. Shielded symmetrical or multi-core cables become quasi-coaxial systems by short-circuiting the internal conductive cores.