phone jack wiring

Installing phone jack wiring is different than it was twenty years ago. We have found a more reliable way to run phone circuits. Phone wiring circuits used to be run using a "daisy chain" wiring method.

phone wiring


Phone jacks have changed a little over the years. With the newer cables like Cat3 and Cat5, the jacks have added a few more terminal screws for extra phone lines. This was probably a good idea.

Still the first two wires that you will connect to will be the red and green wires. That's still the same. The problem is that the new Cat5 doesn't have red and green wires, so you will the blue and white blue wires instead.

Older way of wiring

daisy chain

Daisy chain wiring saves wire by running cable from phone jack to phone jack as illustrated above. The problem is when one phone jack goes bad, (usually from mice chewing on the cable) all the phone jacks behind it go bad also. Cable is cheap these days. It is almost always CAT5 cable.


Newer, better way of wiring

hub wiring


The better method is the "hub topology" or just hub method. As illustrated in the drawing above each phone jack has its own dedicated cable that comes from the junction box. There is a junction box for each phone line in the home. The illustration above shows a home with two phone lines and many phone jacks for each phone line.

Wiring this way helps create "redundancy" for phone systems. Redundancy is probably a bad word in the normal world, but in the computer/communications world, it is completely necessary.

phone junction


A junction lies between the Dmarc block (phone company box) and the phone jacks.

home phone wiring


The phone company will connect the phone box to the residential dwelling. They will bring phone service and connect it into the phone box as shown above.

If you are wiring your own home phone wiring, you will connect the home wiring that comes from the junction box and connect it to the right side of the phone company box. This is simpler than it sounds. See above how the right side of the box has red and green wires? You will connect the green to the marked green screw and the red to the marked red screw.

If you get it backwards you won't get a dial tone once your phones are hooked up. In that case, just switch the red and green leads. It's low voltage, so you won't get shocked. Still, use caution when working with any electrical wiring.

phone wiring diagram


The picture above looks confusing, but just look at the red and green terminals, they are the only ones used for phone wiring. If you're using CAT5 cable then you won't have a green or red in any of the eight wires, but you can use the conversion and do white/blue to the green terminal and blue/white to the red terminal.

Home phone-jack-wiring is very easy to do even though it may seem challenging at first.

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