Types of Phone Cords

By Kristen Marquette

The connector jack and wires of a phone cord determine how many phone lines you can have.
i telephone 4 image by Aussiebloke from Fotolia.com

Vital to the operations of businesses and offices across the country as well as maintaining family and social networks, the telephone relies on a vital component--the phone cord. These modular connectors link your phone to handsets, headsets and the wall jack. They are also responsible for connecting multiple phones and linking phones to computer modems. In the United States, three types of phone cords are most commonly used.

RJ-11 Phone Cord

You probably use an RJ-11 phone cord in your home as they are most commonly used for home telephones. These phone cords also are used in connecting your phone line to your computer's modem so you can access the Internet. The RJ stands for registered jack standard while the number following the abbreviation represents the exact standard of the phone cord. The 11 of the RJ-11 phone cord signifies that it consists of a six connector jack and two wires. It is this connector jack to wire ratio that differentiates phone cords from each other even when they look identical.

RJ-12 Phone Cord

Resembling the RJ-11 phone cord, the RJ-12 consists of a six-connector jack and four wires and is used by large businesses with multiple phone lines. The extra wires in this type of phone cord allows certain phone systems, such as keyed telephone systems and PBXs--private branch exchange telephone systems--to recognize when the one line is being used.

RJ-14 Phone Line

RJ-14 phone cords possess a six-connector jack and four wires like the RJ-12. The extra wires in this type cord let you hook up a second phone line to the same cable with ease. The center wires acts as the main phone line while the outer wires operate the second phone line. You will most likely use an RJ-14 when installing a second home phone line or in a small office environment that requires no more than two phone lines.