need help installing two phone lines on cat5 FREE cabling and networking Helpdesk
 Question by Dan S posted 24 Oct 2005
 need help installing two phone lines on cat5
Can someone show me the wiring diagram for hooking up two different phone lines on cat5. I have one line that is already active, and the phone company has stated that they have activated the second line on the box outside. They want a tidy sum to hook it up inside the house. I'm assuming it isn't rocket science but want to make sure I"m not screwing anthing up prior to running wires. I have my DSL, and two phone lines coming off one jack, and have a three way splitter L1, L2, L1+L2. Be much appreciated if someone can help.
 Answer by Joseph Golan posted 25 Oct 2005
Dear Dan,

This all depends how the existing wiring is done. Unfortunately there are many variables:
1. The type of jack
2. The type of cable
3. If the wiring is home-run or daisy chained
4. If you have two-line telephones or 2 single line telephones

First there should be a box typically outside the home known as the NID (Network Interface Device). There are 2 parts to this box, one for the telco and the other for the user. The user portion opens with a standard screwdriver and inside you will see two pairs of screws, marked line 1 and line 2. You should already find wires connected to line 1 and they are either White-Blue (Twisted pair) or Green-Red (JKT). There should also be spare conductors from the existing cable(s).

For the balance of this I will assume that you have twisted pair cabling, at the end I will give you the equivalent colors for JKT cable.

The next thing is to determine what kind of jacks you have. Basically there are 3 wiring types used at the jacks: T568A; T568B; or USOC. you can find these wiring schemes at these urls:
Newer jacks have it's type stamped on the side. The wiring for T568A and USOC are the same for 2 line systems with the White-Blue as pair 1 (Line 1) and the White-Orange as pair 2 (Line 2). The T568B will have the White-Blue as line 1 and the White Green as Line 2.
So if you have T568A or USOC then connect the White-Orange to line 2 in the NID; if you have T568B then connect the White-Green pair to line 2 in the NID.
If all the cables are home-run to the NID you will see as many cables in the NID as jacks in the home or they could be all run to a central location (basement or garage) with a single cable to the NID. Connect all the pairs together (either the white-orange or white-green pairs, depending upon the jacks) in a like manner to the white-blue pair.

You should then find line 2 at the jacks. Make that your DSL connection does not have one of the DSL line filters or it will not work. The filters are only needed on connections to the telephones (most of them are already set to work with 2-line sets.

For JKT cable use the Black-Yellow in place of White-Orange, JKT cable typically uses USOC jacks.

If you still feel unsure, try getting line 2 to one jack first and test it before doing the others.

There are also several books,especially the "Home Cabling Guide" available at this site, see:

or check out your local Radio Shack or Home Depot for other publications.

Added by Joseph Golan on 10/27/2005 after Dan provided photos of his cabling setup
photo edit by Joseph Golan

Fig 1: Faceplate in the room
The Fig 1 is of a combination Leviton faceplate with a USOC RJ-14, using JKT colors, and and "F" bulkhead. The White of the White/Orange will go to the screw with the Black lead and the Orange of the White/Orange with go to the screw with the Yellow lead. See Fig 1 with notes picture attached.
Fig 2: Network Interface Device (NID) outside
Fig 2 is of the NID and I assume that the White Orange pair seen is the telco side. The customer cable, White/Orange pair will go in the next holes (to the right of it) with the White of the White/Orange in the "T" (Tip) and the Orange of the White/Orange in the "R" (Ring). The copper should be exposed (striped), inserted into the holes and then the salmon lever flipped down to make the connections. These are typically gel filled connection points as seen cleared in picture 1728. You can also see the "test" RJ-11 jacks at the bottom of the picture. See Fig 2 with notes picture attached.
The last thing the owner will need to check is to see if there is a splice point in the home connecting the cable from the NID to his station runs, as there is only one cable in the NID besides the feed from the telco. At that point he must splice all the Whites (of the White/Orange pair) together and all the oranges (of the White/Orange pair) together using a similar method found on the White/Blue pair.
Joseph Golan, RCDD

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