Tamara Wilhite is a technical writer, industrial engineer, mother of two, and published sci-fi and horror author.
What Are RJ45 Cables?
RJ45, short for Registered Jack 45, cables and connectors must meet a host of IEEE, ANSI, TIA and ASTM standards. What do the standards for RJ45 cables mandate? What industrial standards apply to RJ45 cables?
RJ45 Connector and Cable Architecture
RJ45 cables are used in category 5 (cat 5) cables and category 5e (short for category 5 enhanced) cables. Cat5 and cat5e cables are twisted pair of copper cables containing 8 copper wires in 4 twisted pairs.
Cat5 cables are used to carry digital signals such as local area network internet connections and video signals. RJ45 connectors are installed at the end of category 5 and 5e cables to create computer network and signal carrying lines. RJ45 cables typically have an 8 position 8 contact (8P8C) connectors on the end.
Category 6 RJ45 cables are used to connect an Ethernet. These cables must meet EIA/TIA 568B standards for most applications.
RJ45 Cable and Connector Standards
The original JR45 connectors had eight pins, two of were originally meant for telephone lines, but that is obsolete. The RF 45 connectors per IEC 60603-7 standards use an 8P8C modular connector with eight conductors.
RJ45 cables are primarily used in 100BASE-TX and 1000BASE-T Ethernet networks. RJ45 cables must meet Institute of Electrical and Electronics Engineers (IEEE) standard 1394. The 8P8C connectors on RJ45 cables are built to meet American National Standards Institute (ANSI) standard 1096-A.
However, not all 8P8C connectors are connected to RJ45 cables. RJ45 8P8C connector pin assignments are designated by Telecommunications Industry Association (TIA) standard 568B. The copper cable used in RJ45 cat5 cables meets TIA/EIA standard 568-5-A. Category 5 and 5e cables use American Wire Gauge (AWG) 24 wire throughout.
The Relationship Between TIA/EIA/ANSI 568 Standards
TIA 568A and TIA 568B or T568A and T568B are also called EIA 568A and 568B, since the TIA is a spin-off organization of the Electronic Industries Alliance (EIA). TIA standards for telecommunications cables were subsequently adopted by ANSI.
Cables that meet ANSI / TIA / EIA 568 standards do not automatically meet ISO telecommunication cable standards. While TIA standards 568A and 568B were replaced with standard 568C in 2009, many data networks still use cables and connectors designed to meet TIA 568A and 568B standards.
Many RJ45 cables meeting these standards are still in use today because infrastructure such as cables and connectors are slower to change than software.
RJ45 Cable Cover Standards
American Society for Testing and Materials (ASTM) International has created standards for testing materials such as copper wiring. ASTM standard D4566 outlines standard test methods for telecommunication cable jackets and covers. ASTM B193 is the method of verifying the resistivity of the cable covers.
ASTM standard D150 measures alternating current (AC) loss and permittivity of the electrical insulation. The cable covers can also be tested in accordance with IEC standard 61156-1. ASTM D4732 and D4731 are the specifications for filling compounds used in telecommunications wire and cable, typically put in place before RJ45 connectors are attached to the cable.
klanguedoc on January 29, 2012: