ITU-T K.147 (07/2023)
Current
The latest, up-to-date edition.
Protection of digital ports connected to balanced pairs of conductors
Hardcopy , PDF
English
07-01-2023
1 Scope
2 References
3 Definitions
3.1 Terms defined elsewhere
3.2 Terms defined in this Recommendation
4 Abbreviations and acronyms
5 Conventions
6 Overview
6.1 General
6.2 Network power delivery
6.3 Twisted-pair data link and surge protector capacitance
6.4 Twisted pair powering usage
6.5 Link insulation
6.6 Summary of link conductor usage
7 Link voltage, current and resistance values
7.1 Single balanced pair link
7.2 Two and four balanced pair link
8 Surges on network systems
8.1 Surge coupling mechanisms
8.2 Direct coupling – permanent
8.3 Direct coupling – transient
8.3.1 Voltage limiters
8.3.2 Capacitance
8.4 Magnetic coupling
8.5 Electric and electromagnetic coupling
8.6 Surge resistibility design approaches
9 [ITU-T K.44] and [ITU-T K.117] test circuits
9.1 Test circuit overview
9.2 Power fault resistibility
9.3 RP link
Annex A Ethernet surge test circuits based on ITU-T K-series Recommendations
A.1 Introduction
A.2 Ethernet port testing
A.2.1 Test generators
A.2.1.1 1.2/50-8/20 generator
A.2.1.2 AC generator
A.2.2 Untested port termination and coupling network
A.2.3 Common-mode test circuits
A.2.4 Differential-mode test circuits
A.2.5 Ethernet intermediate link connections
A.3 Testing of XDSL ports
A.3.1 Test generators for external port testing
A.3.1.1 Lightning surge generators
A.3.1.2 AC generator
A.3.2 Untested port termination and coupling network for external port testing
A.3.3 Differential-mode test circuits for external port
A.3.4 Common-mode test circuits for external port
A.3.5 External port to another external port
A.3.6 Test generators for internal port testing
A.3.7 Untested port termination and coupling network for internal port testing
A.3.8 Common-mode test circuits for internal port
A.3.9 Differential-mode test circuits for internal port
Appendix I Examples of Ethernet twisted pair DC power feeds
I.1 Introduction
I.2 Powering over one twisted pair
I.3 Powering over two twisted pairs
I.4 Powering over four twisted pairs
Appendix II Networking evolution
II.1 General
II.2 B.2 Universal serial bus
II.3 Profinet
II.4 SPE
II.5 Testing
Bibliography
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