GB/T 31723.406-2026Metallic cable and other passive components test methods - Part 4-6: Electromagnetic compatibility (EMC) - Surface transfer impedance - Line injection 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 4-6 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 31723.406-2015 "Metallic Communication Cables - Test Methods - Part 4-6.Electromagnetic Compatibility - Surface Transfer".

Compared with GB/T 31723.406-2015, the main technical changes in "Impedance Line Injection Method" are as follows, except for structural adjustments and editorial modifications.

---Added terms and definitions for "internal circuit," "external circuit," and "transfer impedance" (see 3.1~3.3);

---The physical context information has been changed (see Chapter 4, 4.2 of the 2015 edition);

---The device has been changed (see 5.2, version 5.2 of 2015);

---The impedance of the internal circuitry has been changed (see 5.4, 5.4.2 in the 2015 edition);

---The matching circuits for Z2 50ohm have been removed (see sections 5.4.3 and 5.4.4 in the 2015 edition);

---The overview of test sample preparation and sample length has been revised (see 6.1 and 6.2, 4.3 and 6.1 in the 2015 edition);

---The formula has been modified (see 7.3~7.5, 2015 version 7.3~7.5);

---The representation of test results has been changed (see 8.1, 2015 edition of 8.1);

--- Added normalized shielding attenuation (see 8.2).

This document is equivalent to IEC 62153-4-6:2017 "Metallic cables and other passive components - Test methods - Part 4-6.Electromagnetic compatibility".

Surface transfer impedance line injection method.

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

---Correct "Lc" to "Lc" in Figures 1, 10 and 11 to be consistent with the index number description;

---In section 6.1, "see h1 and h2 in Figure 7" should be corrected to "see h1 and h2 in Figure 7" to maintain consistency with Figure 7;

---Correct "Ugenerator/Ureceiver" in 6.2 to "Ugen/Urec" to be consistent with formula (6).

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 Absorption Clamp Method for Electromagnetic Compatibility Links and Channels (Laboratory Conditions). The aim is to establish practical...

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

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

A clamp test method for absorbing coupling attenuation of cable assemblies under load.

---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 metal cables and other passive components Parts 4-6.Electromagnetic Compatibility Surface Transfer Impedance Line injection method

1 Scope

This document describes how to obtain surface transfer impedance by applying a defined voltage and current to the cable shield and measuring the induced voltage.

The method was used to determine the shielding effectiveness of shielded metal communication cables.

Measurements are performed using common high-frequency measuring instruments, with a frequency range from several kilohertz to 1 GHz or higher.

2 Normative references

This document has no normative references.

3 Terms and Definitions

The following terms and definitions apply to this document.

internal circuit

The circuit, indicated by subscript 2, consists of the conductors and shielding of the cable under test (CUT).

The circuit, indicated by subscript 1, consists of the shielding surface of the CUT and the injection lines.

transfer impedance

The ratio of the longitudinal voltage induced in the internal circuitry of a cutter with a shorter electrical length per unit length to the current in the external circuitry (line-injected circuitry).

The value is the same as the value, and vice versa.

4 Physical background information

The transfer impedance ZT of the shielding layer is an important parameter for determining the shielding effectiveness of a cable.

Capacitive coupling in most cables is negligible. However, for single-shielded cables, capacitive coupling cannot be ignored.

The coupling through the shielding layer can be described by the capacitive CT or capacitive coupling admittance YC. For a short, uniform cable with a short electrical length, YC is...

It is defined as the ratio of the internal circuit current to the external circuit voltage (composed of the test shield and the injection line) per unit length, and vice versa.

When capacitive coupling is not negligible, the shielding effectiveness is represented by the equivalent transfer impedance ZTE, as shown in Equations (1) and (2).

ZTE = max|ZF±ZT| (1) ZF=jomegaCTZ1Z2=YCZ1Z2 (2)