Frequently Asked Questions

Wiring Standards

Q.

T568A and T568B wiring: what’s the difference, and how do I know which one to use?

A.

T568A and T568B are the two wiring standards for an 8-position modular connector, permitted under the TIA/EIA-568-A wiring standards document. The only difference between T568A and T568B (also known as Weco, AT&T 258A) is that the orange and green wire pairs (pairs two and three) are interchanged.

Standard 4-Pair Wiring Color Codes
Pair 1	T	White/Blue
	R	Blue/White
Pair 2	T	White/Orange
	R	Orange/White
Pair 3	T	White/Green
	R	Green/White
Pair 4	T	White/Brown
	R	Brown/White

Note: For 6-wire jacks use pair 1, 2 and 3 color codes. For 4-wire jacks, use Pair 1 and 2 color codes.

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How to decide which wiring pattern to use:

1. Does the job specification call out a wiring pattern?
2. Does the customer/end user have a preference for T568A or T568B?
3. Have patch panels already been purchased for the job? If so, they will probably be either T568A or T568B. The jacks should be wired to the same pattern as the panels.
4. Are you adding on to an existing wiring plant? If so, your new wiring should match the existing wiring.

If none of the factors above apply, either T568A or T568B may be used. It is important to ensure that the workstation connectors and the patch panels are wired to the same pattern. T568B is commonly used in commercial installations, while T568A is prevalent in residential installations.

Category 5e+ Component Level Patch Cords

Category 5e+ Patch Cords provide an increased level of performance above our standard Category 5e patch cords. These cords accommodate both T568A and T568B wiring applications, and are offered in a variety of popular colors for easy circuit identification. These premium cords exceed component level performance for patch cords as specified in TIA/EIA-568-B.2.

Category 5e+ Component Level Patch Cords

Cat-5e Patch Panels

Category 5e+ patch panels are designed to exceed TIA/EIA-568-B.2 component, permanent link and channel level performance specifications providing usable bandwidth beyond 155 MHz. These high-density panels are available in 12 through 96 port versions and feature enhanced front and rear labeling features for easy circuit identification. Category 5e+ panels support both T568A and T568B wiring configurations using an easy to read color-coded wiring label.

Cat-5e Patch Panels

JDSU Testing and Verification

JDSU Network and Enterprise Test tools are designed for the requirements of customers who install, manage and maintain premises, enterprise, and broadband access networks. These task-ready, or single-task, test instruments are easy-to-use and allow technicians to Know the Network is ready to support the broad set of advanced communications, entertainment, and commercial applications used by consumers and businesses today.

JDSU Testing and Verification

Network & Telephone Inserts

Leviton's snap-in connectors feature dual color coded wiring labels with both T568A and T568B wiring patterns, for dual flexibility in a single connector, plus fast, accurate termination of station wiring.

Network & Telephone Inserts