Commercial Phone Jack Wiring

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Old 12-11-01, 05:58 PM
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Commercial Phone Jack Wiring

Hello, I work in a building and we have a business phone system which has 6 lines. We work off of 4 major lines in the building and the other 2 are private lines. There is an unused jack in an empty office and we would like to make that phone jack active to our lines. Before, a company rented out that office and had their own phone line separate from ours. Now they are gone and we would like to make that jack active to our lines. I already tried to copy the wiring from an active jack in another office to the jack in the empty office. Unfortunately, it didn't work. Can someone please help me get this jack working?
Old 12-12-01, 02:49 AM
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Is this wired with cat-5 cable?

Each cat-5 has 8 wires in it, enough for 4 phone lines. Does the active jack in the other office have 2 cat-5 cables to it? How many actual "sockets" are there at the target location and how many lines do you want there?

The service is usually set up as follows:
line 1 - white/blue|blue pair
line 2 - white/orange|orange pair
line 3 - white/green|green pair
line 4 - white/brown|brown pair

Look here for a schematic on how the jack/cable is wired.

These diagrams are for network cables, but they are based on the 586A and B standard designed for phones.

For 2-line phones (using a single jack), the inside 2 pins of the jack are line 1, the next outer 2 are line 2. So you would need 3 2-line jacks for your 6 lines. You will also need 4-line phone cords from the jack to the phone.

Wire the jacks as follows:
white/blue to green of jack1
blue to red of jack1.
white/orange to black of jack1
orange to yellow of jack 1.

white/green to green of jack2
green to red of jack2.
white/brown to black of jack2
brown to yellow of jack 2.

Use the blue/white|blue pair and the orange/white|orange pair on the second cat-5 cable for lines 5 and 6 on jack3.

If you are installing six separate jacks, one line per jack), you would wire the red of the jack to the white-with-colored-tracer of the cable, and the green from the jack to the solid-colored wire, for each line.
Old 12-12-01, 10:18 AM
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Your mention a un-used jack in an empty office-this is a termination of a cable.Where does that cable connect to the telephone service?
Old 12-12-01, 10:53 AM
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switchman has likely hit on the problem. The cable from this jack is separate from the cables from the other jacks. It doesn't matter how you hook up this jack because the cable isn't connected to anything at the other end. It might even go to a different outside box.

Look around your building for outside phone boxes. You might find more than one. Look in all of them to find a cable where none of the wires are connected to anything. Or, even more likely, the wires will be connected to a connection block, but the phone company has deactivated the line to that connection block.

If you only have one box, you can probably fix this problem by rearranging the connections in that box, moving the wires from the dead connection block to one of the live ones. If you have two boxes, you may need to run a new cable between them.
Old 12-12-01, 03:03 PM
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Thank you for your help. I will see if I can find an additional outside box.
Old 12-12-01, 05:23 PM
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If it's a typical office building with a drop ceiling then it might be just as easy to run a wire into the office. The drop will be lower than the top of the wall so you can easily make a hole in the drywall and drop the cable down to the jack.
Old 12-13-01, 03:50 AM
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Are you using a "key" phone system? If so you'll have to wire the extra jack back to the main box. You may also have a limited number of extensions available on such a system. Look for that box first and look to see if there are availble ports before you run the wires.
Old 07-30-14, 01:36 PM
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Because you had a previous tenant there with their own telephone line.
Your local telephone company would have set up a separate demark for them.
You will have to find this demark location (point of service entry into bldg) (usually found by a hydro panel or outside of bldg by hydro meter)
Once the demark point is found you will have to reroute those wires or run a new wire to your operational demark point.
That's the only way that line will work as it is presently separate from your system
Old 07-30-14, 02:24 PM
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Olivetree: Welcome to the forums. Please check the dates next time, you responded to a question from more than 12 years ago.
Old 07-30-14, 02:25 PM
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Wow, this is a 13yr old thread and hardly anyone is even a member any more!
Thank you for your reply, however, it would be more beneficial to reply to current members with current problems. This will help no one.

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