Wiring Standards

Wiring StandardsT568A/B vs EIA/TIA 568

People often confuse the TIA/EIA-568-B wiring standard with the T568A or T568B pin/pair assignment defined in this standard. According to this excerpt taken from Wikipedia.org, “TIA/EIA-568-B specifies that horizontal cables should be terminated using the T568A pin/pair assignments, or, optionally, per [T568B] if necessary to accommodate certain 8-pin cabling systems.” Despite this instruction, many organizations continue to implement T568B for various reasons, chiefly associated with tradition (T568B is equivalent to AT&T 258A). The United States National Communication Systems Federal Telecommunications Recommendations do not recognize T568B.”

T568A standard uses orange for line 2 and green for line 3, where T568B uses green for line 2 and orange line 3. Both are equal in performance, but care should be taken not to mix these wiring codes in the same installation (i.e., jack and patch panel must be wired the same). The same product can be used for either, as long as the pair order corresponds correctly. Most residential products are color-coded for T568A wiring as the default wiring standard.

CEA-863-A StandardConnection Color Codes for Home Theater Systems

These colors are defined by industry standards to make commonly used connections for electronic devices in a home theater system easy to identify. The following is a list of signal connections that reference the CEA-863-A standard for “Connection Color Codes for Home Theater Systems.”

Yellow Composite Video
White Digital Video – Coaxial
Orange Digital Audio – Coaxial
Green Component Video
Grey Sync, Horizontal Deflection
Black Sync, Vertical Deflection
Red Component Video (CH3, R)

Other color ring indicators such as green indicate the use for an RG6 compression connector for coaxial cable and red for an RG59. These two are the most commonly used for video coax applications inside the home.

Cabling Application NotesHDMI™

The HDMI Specifications do not specify cable lengths. However, for long cable runs the following is recommended:
If you need to send a 1080p signal more than 25 feet, or a 1080i signal more than 49 feet, active electronics will help clean up and boost an HDMI signal when it’s traveling long distances. You can purchase either a stand-alone booster or an active cable, where the circuitry is embedded in the connectors themselves. In both cases, the connection requires a power source.

HDMI over CAT5e/6:
Runs of up to 50 meters can be achieved by sending the HDMI signal over a run of CAT5e/CAT6 networking cable, using special adapters designed for this purpose. These products incorporate booster and equalization electronics at each end of the path and require external power. Because of its tighter manufacturing tolerances, CAT6 cable is generally preferred over CAT5 in these applications.

For more info on HDMI see: http://en.wikipedia.org/wiki/HDMI