Crimping an RJ45 Connector Correctly

Proper Wiring For Ethernet Cat5/Cat5e Cables

RJ-45 Ethernet ConnectorCables can transmit information along their length. To actually get that information where it needs to go, you need to make the right connections to an RJ45 connector.

Your cable run needs to terminate into a connector, and that connector needs a jack to plug into.

Registered Jack 45 (RJ45) is a standard type of physical connector for network cables. RJ45 connectors are commonly seen with Ethernet cables and networks.

Modern Ethernet cables feature a small plastic plug on each end of the cable. That plug is inserted into RJ45 jacks of Ethernet devices. The term “plug” refers to the cable or “male” end of the connection while the term “jack” refers to the port or “female” end.

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RJ-45 Connector with Protective Cover InstalledRJ45 plugs feature eight (8) pins to which the wire strands of a cable interface electrically. Each plug has eight locations (positions), spaced about 1mm apart. Individual wires are inserted using special cable crimping tools. The industry calls this type of connector 8P8C (Eight Position, Eight Contact).

Ethernet cables and 8P8C connectors are crimped into the wiring pattern to function. 8P8C can be used with other types of connections besides Ethernet; it is also used with RS-232 serial cables, for example. Because RJ45 is by far the predominant usage of 8P8C. Industry professionals use those two terms interchangeably.

T568A or T568B Wiring Standard

RJ45 T568A Compared To T568B Wiring Standards

T568A and T568B are the two color codes used for wiring eight-position modular plugs. Both are allowed under the ANSI/TIA/EIA wiring standards. The only difference between the two color codes is that the orange and green pairs are interchanged.

There are no transmission differences between T568A and T568B cabling schemes. North America’s preference is for T568B. Both ends must use the same standard. It makes no difference to the transmission characteristics of data.

T568B wiring pattern is recognized as the preferred wiring pattern.

Wiring an RJ45 to the T568B Specification

Wiring an RJ45 to the T568B Specification

When wiring the connector, follow the layout shown. Your connector will conform to the T568B standard.

Use a good quality crimping tool along with quality connectors.

How to Crimp an RJ45 to Cat5e or Cat 6 Cable

How to Construct a Crossover Cable

RJ45 Crossover Cable Pinout