Extending phone lines

outsource_locally

Prominent
Oct 4, 2017
8
0
510
I need to move 2 Comcast business phones from one suite in a building to another (approximately 150ft). Ideally, I don't want to move the modems because the move is temporary. What is the best way to do this? I was thinking of adding an extension to the current drops and running that through the drop tile ceiling. Will I experience deminished quality for the distance I'm running?
 
Solution
Do you know what kind of phone lines these are? If they're regular analog phone lines, then extending them is trivial. In fact you may only need a single extension. Regular phone lines are one twisted pair. The 4-conductor phone jacks in most homes or offices carry two phone lines (center two conductors are main line, outer two conductors are the second line). So you just extend one line, and wire the two pairs to a two-outlet phone outlet.

If these are digital phone lines however (typically office phones with features like extension numbers, forwarding, hold, multi-line, etc), they may be running on two or even three twisted pairs (4-conductor or 6-conductor lines). Not all office phones with these features are digital however...
Do you mean just for phone service or asking how to extend the internet without moving the modems. If it is just phone it is simply run the wire and splice it back to the phone lines

First be sure you are allowed to run cable in the ceiling, this will be part of the lease unless you own the building.

Next most time the building codes require you to run what is called plenium cable in a drop ceiling. Rules related to commercial building are such a pain but they are worried about fire. Even if you can sneak it by the city your insurance will likely not pay out if there is any liability related to things that were not installed to the codes.
 

outsource_locally

Prominent
Oct 4, 2017
8
0
510


So I'm doing this for the building owners, so I already confirmed I could run along the ceiling. They are wanting to keep the comcast internet and phone modems in the main location and move the router and devices (2 computers, 2 phones) to the temporary location. I have plenum cable for the ethernet, and have not yet purchased the cabling for the phones. Moving the internet connection should be simple enough just by running an ethernet cable from the modem in the main location to where the router will be in the temp spot. It's just the phones I'm concerned about.

I've done network cabling before, but I'm very inexperienced when it comes to phones. My thoughts for the easiest solution are to take off the wall plates where the phone jacks are (where the 2 phones reside) and connect a long cable to each current line and run that up through the wall and across the ceiling to the temporary spot.

 
Do you know what kind of phone lines these are? If they're regular analog phone lines, then extending them is trivial. In fact you may only need a single extension. Regular phone lines are one twisted pair. The 4-conductor phone jacks in most homes or offices carry two phone lines (center two conductors are main line, outer two conductors are the second line). So you just extend one line, and wire the two pairs to a two-outlet phone outlet.

If these are digital phone lines however (typically office phones with features like extension numbers, forwarding, hold, multi-line, etc), they may be running on two or even three twisted pairs (4-conductor or 6-conductor lines). Not all office phones with these features are digital however. You can usually (but not always) tell by looking at the connector on the phone itself, and count how many contact pins it has.

Generally distance is not a problem. Cat 3 phone line is good up to several km. The twisted pair rejects noise.

https://en.wikipedia.org/wiki/Differential_signaling


Plenum cable is required when the air space above the drop ceiling is part of the ventilation system (called a plenum space). e.g. air from the air conditioning comes out vents in the ceiling. But the return air vent is located in the plenum space.

If the air space above the drop ceiling is dead space (non-ventilated), then you can toss whatever low-voltage cables up there that you want. Although you shouldn't do anything stupid like laying cables across light fixtures which might heat up.

https://en.wikipedia.org/wiki/Plenum_space

The idea is that if there's a fire, the burning cable could give off toxic fumes. If the cables are in a plenum space, the building's ventilation system could carry those toxic fumes to areas of the building which haven't yet been evacuated. The jacket on plenum cable is fire retardant to minimize this danger.
 
Solution

outsource_locally

Prominent
Oct 4, 2017
8
0
510


That makes perfect sense, thank you! I hadn't even thought of that but you are right. That makes this much easier :)

Thanks so much for sharing your insight!

 

outsource_locally

Prominent
Oct 4, 2017
8
0
510


I'll need to double check the type of phones, but I believe the connection coming from the phone modem is two twisted pairs. Thank you to you and Bill001g for sharing your insight. I wouldn't have considered this myself as I'm inexperienced with phones. Now I know how to plan for this!