Phone Line

Two lines, no waiting

If you're tired of juggling your phone, fax, and modem on a single line, it may be time to install a second. The phone company will happily charge you both an activation fee and, if your internal wiring isn't connected, an installation fee.

There's not much you can do about the activation fee, since only the phone company can assign you a new phone line and connect it from its wires to your house. But installation is within your control. You can either hire an electrician or another third party to do it (usually for a little less than the phone company), or you can do it yourself with a few common tools and the right hardware.

This writing will walk you through the basics of both connecting an existing jack to a new phone line and installing a new jack.


What does a phone line look like? It's a cable from the phone pole on the street to a box in your house. This cable is insulated (covered with a plastic sheathing), and inside the insulation are usually four to eight insulated copper wires.

One phone number needs two of these wires, called "tip" and "ring" wires, to work. So if you already have one working phone line in your house, you probably also have the wiring needed for at least one more line--that is, you have at least one more pair of tip and ring wires.

This writing should apply in most U.S. residential situations, though some wiring or equipment may look different than that described here, especially if it's old. If this is the case for you, the manager of your local hardware store may be able to help you sort it out--or you may need to call the telephone company or an electrician after all.

Some words of caution. Phone lines carry a small electrical charge. To avoid getting a jolt, disconnect your line where it comes into your house whenever you work on the wires (disconnection is described in Step 3). Don't do any wiring work if you wear a pacemaker. Avoid working with wet feet or during an electrical storm, and keep uninsulated wires dry.

Step1:Find the Network Interface Device (NID)

The network interface device (NID) is where your phone line enters your house or apartment building. It's a gray box with a cover on it. To find it, follow the phone line from the pole on the street nearest to your building. If it's not on the outside of the building, look inside close to where the line enters the house. NIDs are often attached to basement or closet walls or floor joists.

Do you need to rewire? If all the wiring is properly done in your NID and in your existing wall jack(s), activation will give you access to your new phone line. All you need is a two-line phone or jack adapter, which plugs into an existing jack and splits its current into two or three possible configurations: line 1, line 2, and/or both lines (for a two-line phone).

You can wait until the phone company has activated the new line, then plug a phone into the left and middle holes of the adapter and listen for a dial tone. If you get tones in both, the jack is wired. Or you can follow Step 3 through Step 5 to determine whether the connections are made at the NID and your chosen jack.

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Note: If you live in an apartment building, it's likely that several apartments share an NID. You may need your landlord's help finding it--and, in any event, you should tell him or her you're installing a new phone line in your apartment. Depending on your lease, the landlord may be responsible for the installation--or may just prefer to do it him or herself.

Step2: Order a New Line

Call your local telephone company and request a new phone number. The representative will ask you to choose the services you want (voice mail, call waiting, and so on) and your long-distance provider.

The representative will also arrange a time for a technician to come to your house and activate your new phone line. Tell the representative where the NID is, and, if it's inside, arrange to be there to give the technician access. (Or ask your landlord or building manager to let the technician in.)

Step3: Check the NID Connections

The NID usually has two covers: one for the outside line (marked "telephone company access only") and one for the inside line (marked "customer access"). Everything you need to be concerned with is in the customer access side of the NID.

Open the NID. Inside the customer access side of the NID, you'll see one or more phone jacks just like the square holes on your phone and your wall jacks. The outside line, which enters from the phone company's side of the NID, should be plugged into one of them. Colored wires run between these "test jacks" and pairs of terminals, which are color coded green and red (and sometimes black and yellow). The terminals usually look like metal screws or nuts.

The line that goes to your wall jacks is also connected to these terminals. This line is an insulated cable containing four to eight smaller copper wires, each insulated in different colored sheathing. These wires emerge from within the larger cable sheathing inside your NID. If you have one active phone line, at least two of these wires will be connected to two of the terminals: the tip (T) wire to a green terminal and the ring (R) wire to a red terminal.

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What the colors mean. Different colors of insulated sheathing are used to differentiate between the pairs of wires. There are two standard color systems used in most residential wiring. In a four-wire cable (which is standard to many single-family homes), the first pair is green (T1) and red (R1), and the second pair is black (T2) and yellow (R2). If this is what you have, the black and yellow wires will carry your second line. (Six-wire line may also use these colors, with a third pair colored blue [T3] and white [R3].)

In most cable with more than two pairs of wire, two-color insulation is used. You probably won't encounter a cable with more than four pairs (eight wires). These wires have stripes of white and another color: blue (line 1), orange (line 2), green (line 3), and brown (line 4). The tip line is white with stripes of the second color, while the ring line is the second color with stripes of white. So in this scheme, T1=white/blue, R1=blue/white; T2=white/orange; R2=orange/white; and so on.

Connect the T2 and R2 wires. If your T2 and R2 wires are not already attached to their terminals, attach them to the unused pair.

First, disconnect the outside wires from the test jacks in the NID by removing the plugs from the test jacks (just like unplugging a phone). Using your wire stripper, remove about 3/4 inch (2 centimeters) of sheathing from the T2 and R2 wires, exposing the copper. Loosen the T2 and R2 terminals with a screwdriver or wrench and wind the ends of each wire once or twice around its terminal shaft, right below the top of the terminal. If there are metal washers on the terminal shaft, attach the wire between two of them. Remember to attach the T2 wire to the green (or black) terminal, and the R2 wire to the red (or yellow) terminal. Gently tighten the terminals, being careful not to damage the wires.

Plug the outside wires back into the test jacks, fold the wires into the NID, and close it.

Note: If your NID has two pairs of terminals, you should attach the T2 and R2 wires to the unused pair. But there may be more than two pairs. If they aren't labeled clearly with the phone numbers they serve, ask the phone company technician to label them for you when he or she comes out to activate the new line.

Step4: Map the Jacks

If you have more than one telephone connected to your first line, chances are your jacks are wired together, forming a circuit that starts--and sometimes ends--at the NID.

In some houses, a single cable runs from the NID to a more centrally located junction box. The junction box is usually the size of a wall jack, but it can be several times larger. From here, individual cables run out to each jack. If you have this configuration, you will need to connect line 2 at the NID and the junction box, then run a new cable from the junction box to a new jack (see Step 6). Study how the connections are made in your junction box, then copy them.

How jacks are wired together. The jack where the line from the NID is first connected is the "initial" jack. The phone cable enters the jack and its wires are connected to terminals there. Then the cable exits the jack and runs to the next jack, and so on. At the last jack in line (the "terminal" jack), the ends of the wires are connected to terminals, and no cable exits the jack. Alternatively, the last jack may be wired back to the NID, forming a loop.

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If one of these connections is broken, jacks further down the line go dead. So when you rewire one or more jacks for a new phone line (or install a new jack), you need to maintain the existing connections (which service your first phone line) as well as make new ones.

Diagram your circuits. Follow the phone cable from the NID to the first jack it reaches. Then trace it to each subsequent jack until you come to the last jack, or back to the NID. Draw a diagram of your jacks and the lines between them, including the NID, then add in any new jacks you plan to install. This will help you understand what parts of the wiring circuit need to stay intact for both lines to work.

Step5: Rewire an Existing Jack

If you like, you can rewire an existing jack to access a new phone number.

Before you touch the wires, disconnect the outside line(s) at the NID by pulling the plugs out of the test jacks.

Open the jack. Unscrew the jack cover. Inside you should see the cable with four to eight wires emerging from it, and at least two pairs of color-coded terminals (possibly attached to the back of the jack cover itself).

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At least two of the wires will be connected to two of the terminals. This is your existing phone line. If it's not the last jack in the circuit, wires will also lead from these terminals back into a phone cable to service the next jack in line or return to the NID.

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If a second pair of wires (either a black and a yellow or white/orange striped) are connected to another pair of terminals, then this jack is already wired for a second line. Close the jack, wait for the phone company to activate your line, and go to Step 6.

Another set of very short, color-coded wires may be visible (possibly attached to the jack cover), connecting the terminals to the part of the jack where your telephone cord plugs in. Don't detach these; they carry the current from the jack to your phone cord.

If you want to install a new jack in a new location, jump to Step 7.

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Connect the T2 and R2 wires. If the second pair of wires isn't connected to its terminals, connect them now. The T2 terminal is usually either green or black and the R2 terminal is usually either red or yellow. (Or they may correspond to the other color system described in Step 3.)

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There are many different jacks available, with different-looking terminals: The terminals may be metal screws or nuts, or they may be a row of plastic clips with metal contacts inside. Study how the existing connection is made and copy it.

More jacks? If you want to wire another jack for the second line, connect the outgoing wires to the terminals, too. Then go to the next jack down the line and continue the connection.

When you're done, reconnect the outside line(s) to the test jack(s) in the NID. Plug a jack adapter into the wall jack to access either phone line.

Step6: Check the Connections

Once the phone company has activated your line and you've hooked up your jacks, it's time to test both of your phone lines.

Check for dial tones. Plug a phone into each jack you wired for line 2. If you have a dial tone, you're connected. Do the same for each line 1 jack (to make sure you didn't break the existing connection).

If any of the jacks has no dial tone, take a working phone to the circuit box and plug it into the test jacks for each line. If you don't get a dial tone in each line (and you're sure the phone you're using works), call the phone company--the problem is on their end. If you get dial tones, the problem is somewhere in your internal wiring.

Troubleshoot. Check your connections to make sure the circuits are complete from the NID to the terminal jack for each line. Check also that the color coding matches at each connection. If the connections look correct, check for damaged wire along the circuit. If the wire looks intact, but the phone line isn't working properly, it may be time to call in a professional phone technician.

Call yourself. If you have dial tones, call the line 2 number from a line 1 phone and make sure it's ringing in each of the rooms where you connected it. If it's not, make sure the phone you're using works (by plugging it into a working line 1 jack). Then check that it's plugged into the right hole in your jack adapter. Then check the jack's wiring--it may still be wired for line 1.

Each phone configuration is unique in some way, but the preceding guidelines should help you install a second line with ease--and at a fraction of the usual cost.

Step7: Install a New Jack (Optional)

If you want your new phone to be in a room where there's no current jack, you'll have to install one. This step describes wiring a new one-line jack for only line 2, leaving the existing circuit for line 1 intact.

Before you start, disconnect the outside line(s) from the test jack(s) in the NID.

Measure the distance. Starting from the existing jack nearest your new jack location, determine the path the connecting phone cable will take. Measure each part of the path to determine how much cable to buy.

Connect the T2 and R2 wires. Make sure the NID and the jacks up the circuit from the new jack are wired for the second phone line (see Step 3 and Step 5).

Run the new cable. Attach outgoing T2 and R2 wires from your new piece of cable to the T2 and R2 terminals in the nearest existing jack. Using cable staples every few inches (8 to 10 centimeters), secure the cable along the route you measured to the new jack location. Note: Be careful to hammer in the staples around the wire, not through it. The staple point can damage the wire and break the phone connection.

Attach the new jack. Using the hardware that came with your new jack, mount the jack's base to the wall or baseboard. Feed the incoming cable into the back of the jack and connect the T2 and R2 wires to the T1 and R1 terminals (these are the active terminals on your new, single-line jack).

Note: If you want your new jack to host line 1 as well as line 2, you will have to connect the new cable's T1 and R1 wires at both ends, and install a new two-line jack. If you want to continue the circuit for either line 1 or line 2, you will have to run a new outgoing cable from the new jack to the next jacks in line. Remember, if you wire a jack for both lines, you'll need a jack adapter to access them.