1986 Condo Telephone Wiring. Don't Understand.
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1986 Condo Telephone Wiring. Don't Understand.
I don't understand my telephone wiring. Could someone help me understand what's going on here?
I own a condo built in 1986 on the top floor (3rd floor) of my condo building. It has 2 telephone jacks, one in the kitchen and one in the master bedroom.
I'm trying to understand the wiring. I believe it's what's called "continuous loop", versus the home-run type of wiring.
The kitchen jack has 4 cables coming into it. See photo (ignore the upper right cable, that's something else). One pair of cables comes into the bottom of the workbox, which I believe comes up from the telco box on the outside of the building at ground level. One pair of cables comes into the top of the workbox, which I believe goes to the bedroom jack.
The bedroom jack has one pair of cables coming into the top of the workbox, which I believe comes from the kitchen jack.
I don't undertand how this is wired and why there are 2 pairs of cables. It seems like there would only need to be 1 cable coming up from the telco box into the bottom of the kitchen workbox, then 1 cable going from the kitchen workbox to the bedroom workbox. Not sure I understand why there are 2 of each. Can someone explain to me how this works?
I own a condo built in 1986 on the top floor (3rd floor) of my condo building. It has 2 telephone jacks, one in the kitchen and one in the master bedroom.
I'm trying to understand the wiring. I believe it's what's called "continuous loop", versus the home-run type of wiring.
The kitchen jack has 4 cables coming into it. See photo (ignore the upper right cable, that's something else). One pair of cables comes into the bottom of the workbox, which I believe comes up from the telco box on the outside of the building at ground level. One pair of cables comes into the top of the workbox, which I believe goes to the bedroom jack.
The bedroom jack has one pair of cables coming into the top of the workbox, which I believe comes from the kitchen jack.
I don't undertand how this is wired and why there are 2 pairs of cables. It seems like there would only need to be 1 cable coming up from the telco box into the bottom of the kitchen workbox, then 1 cable going from the kitchen workbox to the bedroom workbox. Not sure I understand why there are 2 of each. Can someone explain to me how this works?
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Redundant cabling. It was done that way for a number of possible purposes. The primary reason is in case the occupant wanted two separate telephone "lines" (numbers) in which case each incoming cable would be a separate line/number.
The secondary reason is that back then they used a wall-wart transformer to provide power for the dial light on telephones so equipped. These were the black and yellow conductors. Today dial lights are powered from the telephone line itself.
The third reason is in case the first cable gets damaged in some way there is a spare that can be used.
As to how to wire; you first need to determine which incoming cable has the dial tone from the central office. You can then ignore the second incoming cable. Parallel this incoming cable, matching colors, to one of the cables going to the bedroom and ignore the second cable. On each conductor splice you should add a same-colored pigtail to go to the jack where you match colors or if the jack is marked with a T and R the green wire is connected to T (or tip) with the yellow and black wires ignored.
There ARE alternate wiring plans but this is the most common.
The secondary reason is that back then they used a wall-wart transformer to provide power for the dial light on telephones so equipped. These were the black and yellow conductors. Today dial lights are powered from the telephone line itself.
The third reason is in case the first cable gets damaged in some way there is a spare that can be used.
As to how to wire; you first need to determine which incoming cable has the dial tone from the central office. You can then ignore the second incoming cable. Parallel this incoming cable, matching colors, to one of the cables going to the bedroom and ignore the second cable. On each conductor splice you should add a same-colored pigtail to go to the jack where you match colors or if the jack is marked with a T and R the green wire is connected to T (or tip) with the yellow and black wires ignored.
There ARE alternate wiring plans but this is the most common.
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Is this what a telephone continuous loop looks like, assuming that's what I have in my condo?
If so, what's the purpose of the "return" path? Why doesn't it go from Telco to Kitchen to Bedroom, and terminate at the Bedroom?
The cables are cut inside the workboxes, so I assume at one time they were not cut and continuous and would have had the insulation stripped off the individual red/green wires to attach to the screw-down terminals of the jack itself.
So, if this is how it's wired, to disconnect from the telephone company but still have the kitchen and bedroom wired to each other, I would just make sure to not connect BOTH wires coming up through the bottom of the Kitchen workbox?
If so, what's the purpose of the "return" path? Why doesn't it go from Telco to Kitchen to Bedroom, and terminate at the Bedroom?
The cables are cut inside the workboxes, so I assume at one time they were not cut and continuous and would have had the insulation stripped off the individual red/green wires to attach to the screw-down terminals of the jack itself.
So, if this is how it's wired, to disconnect from the telephone company but still have the kitchen and bedroom wired to each other, I would just make sure to not connect BOTH wires coming up through the bottom of the Kitchen workbox?
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Redundant cabling. It was done that way for a number of possible purposes. The primary reason is in case the occupant wanted two separate telephone "lines" (numbers) in which case each incoming cable would be a separate line/number.
#5
This is what I think you have. I have shown only the working cable. The phone would be connected to where the incoming and out going wires are connected. Usually red and green are used. This can either be a "buss run" where it ends at the last jack or a "loop" where the last jack connects back to the NID.
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Your diagram suggests, and I think user Furd was saying that I probably have (2) bus runs, one for operation and one for redundancy.
My diagram and assumption is a loop, the last jack (bedroom) looping back the way it came, back through the kitchen jack, then back down to the NID. But I don't know why.
What would be the point of having it loop back to the NID? Would there be some kind of terminator on the free end inside the NID? Would the free end just dangle inside the NID? Would it be punched down to an unused block?
This can either be a "buss run" where it ends at the last jack or a loop where the last jack connects back to the NID.
What would be the point of having it loop back to the NID? Would there be some kind of terminator on the free end inside the NID? Would the free end just dangle inside the NID? Would it be punched down to an unused block?
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"So, if this is how it's wired, to disconnect from the telephone company but still have the kitchen and bedroom wired to each other, I would just make sure to not connect BOTH wires coming up through the bottom of the Kitchen workbox?"
Yes, first determine which is from the central office. You could cut a line cord and touch the red/green (or 2 center conductors) to the red & green from the cables until you have dial tone. Mark that one for reference - then connect the others to the red and green of the central office cable and check for dial tone bedroom.
Are you planning to install internet phone service with an ATA (Analog Telephone Adapter)? If yes then leave the central office cable disconnected, and the kitchen and bedroom to each other as you said.
Yes, first determine which is from the central office. You could cut a line cord and touch the red/green (or 2 center conductors) to the red & green from the cables until you have dial tone. Mark that one for reference - then connect the others to the red and green of the central office cable and check for dial tone bedroom.
Are you planning to install internet phone service with an ATA (Analog Telephone Adapter)? If yes then leave the central office cable disconnected, and the kitchen and bedroom to each other as you said.
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What would be the point of having it loop back to the NID?
Would the free end just dangle inside the NID? Would it be punched down to an unused block?
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Are you planning to install internet phone service with an ATA (Analog Telephone Adapter)? If yes then leave the central office cable disconnected, and the kitchen and bedroom to each other as you said.
I've done this before, I'm just trying to avoid having a live cable from Verizon connected to the wiring.