ANSI/TIA-570-B

ANSI and TIA published ANSI/TIA-570-B-2004, or the Residential and Light Commercial Telecommunications Cabling Standard, to address the growing need for "data-ready" homes and multidwelling residential buildings. Just a few years ago, only the most serious geeks would have admitted to having a network in their homes. Today, more and more homes have small networks consisting of two or more home computers, a cable modem, and a shared printer. Even apartment buildings and condominiums are being built or remodeled to include data outlets; some apartment buildings and condos even provide direct Internet access.

Cabling @Work: An Example of Poor Grounding

One of the best examples we can think of that illustrates poor grounding practices was a very large building that accidentally had two main grounds installed, one on each side. (A building should only have one main ground.) A telecommunications backbone cable was then grounded to each main ground.

Under some circumstances, a ground loop formed that caused this cable to emit EMI at specific frequencies. This frequency just so happened to be used by air traffic control beacons. When the building cable emitted signals on this frequency, it caused pilots to think they were closer to the airport than they really were. One plane almost crashed as a result of this poorly grounded building. The FAA (Federal Aviation Administration) and the FCC (Federal Communications Commission) closed the building and shut down all electrical systems for weeks until the problem was eventually found.

The ANSI/TIA-570-B standard provides requirements for residential telecommunications cabling for two grades of information outlets: basic and multimedia cabling. This cabling is intended to support applications such as voice, data, video, home automation, alarm systems, environmental controls, and intercoms. The two grades are as follows:

Grade 1 This grade supports basic telephone and video services. The standard specifies twisted-pair cable and coaxial cable placed in a star topology. Grade 1 cabling requirements consist of a minimum of one four-pair UTP cable that meets or exceeds the requirements for Category 5e, a minimum of one 75-ohm coaxial cable, and their respective connectors at each telecommunications outlet and the DD. Installation of Category 6 cable in place of Category 5e cable is recommended.

Grade 2 Grade 2 provides a generic cabling system that meets the minimum requirements for basic and advanced telecommunications services such as high-speed Internet and in-home generated video. Grade 2 specifies twisted-pair cable, coaxial cable, and optionally optical fiber cable, all placed in a star topology. Grade 2 cabling minimum requirements consist of two four-pair UTP cables and associated connectors that meet or exceed the requirements for Category 5e cabling; two 75-ohm coaxial and associated connectors at each telecommunications outlet and the DD; optionally, two-fiber optical fiber cabling. Installation of Category 6 cabling in place of Category 5e cabling is recommended.

The standard further dictates that a central location within a home or multitenant building be chosen at which to install a central cabinet or wall-mounted rack to support the wiring. This location should be close to the telephone company demarcation point and near the entry point of cable TV connections. Once the cabling system is installed, you can use it to connect phones, televisions, computers, cable modems, and EIA 6000-compliant home automation devices.