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Using CAT 6 for phone wire 1

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lanwan

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Dec 2, 2002
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Has anyone experienced phone issues when using CAT 6 cable for phone wire? Does this cause a problem? I'm having trouble researching this issue. Know of any helpful links?
 
It shouldn't cause any problems, but for standard voice it is overkill. You can run voice on pretty much any twisted pair of wires.


jeff moss
 
like jeff said there is no advantage keep in mind that POTS service reachs your DEMARC on cable that is probably not evan up to cat 3 standards.

it is a interesting question though I rember when cat 5 cable first came out reading that it shouldnt be used for POTS service becouse it could cause cross talk and other problems

we use it all the time though never seen any problem in fact we dont evan carry cat 3 cable any more

so to answer your question I dont think you will see any problems in using the cat 6 cable and of course its nice to have in the wall for future needs
 
I've seen weird problems with Cat5/Cat5e over LONG distances causing major cross talk and static (touch tone tommy, tell everyone the story you told me) but that was about 800-1000 feet I think.

With cat6... I'm sure the same would exist, although cat6 with webbing might not have that problem. I'm not sure.

Bottom line -- I used Category 3 wire for voice if I'm pulling plenty of extra data, to where I know that the voice cabling could never be required for data usage. Category 3 wire is MUCH easier to terminate and work with.
 
I am doing some residential work now, and the customer bought the cable. When he went to ADI to buy cable, they told him there was no such thing as Cat3 cable, so they sold him quad wire. Go figure on that one.

jeff moss
 
I use General Cable Cat3 also, and usually General Cable or CommScope Cat5e.

jeff moss
 
I am doing some residential work now, and the customer bought the cable. When he went to ADI to buy cable, they told him there was no such thing as Cat3 cable, so they sold him quad wire. Go figure on that one.


I hope you dont plan to use the quad wire

 
he only has one phone line now, so I did put it in. I also installed 2 cat5e in each box and one RG6 coax.

jeff moss
 
Hi Avaya Novice,

I would like to know more about this "CAT5/e story" with TTT. Can you enlighten us? What kind of phones were being used etc., because I have never had a crosstalk problem using "electronic" or digital phones - only analogue and that means 500/2500 series type phones or the analogue side from the CO or basically TIP/RING dialtone. This could or would be caused by split pairs, bad terminations, or resistance shorts.

Also those interested might check the cable manufacturers' websites for more info on specific cable and white papers that may provide some good insite into design and applications. You can even call them and talk to an engineer with specific questions. This would surely clear up any erroneous information about the proper use of cable types and the side effects thereof.

BTW, I like General Cable's CAT3 also. It's a good product!

....JIM....
 
Jim,

As I recall... Tommy and I were discussing CO feeders... and it was a rural residence that had twisted pair dialtone drop cable from the pedestal, in conduit, to the SNI. I want to say it was in the range of 1000 feet plus. And it was long ago to where it was definetely an analog telephone. I recall him saying that as soon as they put in NON twisted pair cable, it was fine. I think it was two pair twisted, this was in the 80's if I recall.

I'll have to ask him about it tomorrow.
 
Like I mentioned earlier we dont evan carry cat 3 anymore we use 5e for everything

we rarely run lines that will be strictly analog POTS usually just a fax or modem drop and well under 500' much less a 1000

I have a quanity of cat4 8 pair that I picked up cheap and we often use it to extend demarcs but again usually 100- 300 ' naver seen any problem though

as to the quad wire I can garantee you will have problems if you try to add a second line ..not worth the effort to install in my opion.

 
The weird thing about this is... most of the outside plant work I have done with telephones has been with big big big cables, in the 600-1800 pair category, and a lot of them were VERY old, not quite lead sheath, but almost -- and the twist in those is about every 3-5 feet, not to mention that it's 26 guage conductor. And I never really had any problems with crosstalk there either... most of my splices were either 710 if I had available space in a splice enclosure, or with smaller splice enclosures -- beans to keep the size down. And we're talking 10-20 miles here...
 
I did the install this week with the quad wire. So far, I have the jacks and blocks terminated and I'm waiting to go back and terminate the feed cables. When the job is done, I will post some pictures here. This week I'm also getting some Snap-N-Seal connectors to terminate the coax for this job, I have not used them yet, hopefully they will work well. (from what I read here, they work very nicely)

jeff moss
 
Hey Avaya~
I think the senario that you are remembering was a little different. The rural customer could only get an MPOE at the edge of their property, and had to run their own cable to the house, about 700' or so. They put in their first line themselves, using the two Tips of the two pairs. When they added a 2nd line, they used the two Rings, and had terrible crosstalk. When we straightened it out properly, the crosstalk vanished. Not sure why using Cat5 or even Cat6 would cause any problems with a dial tone though. I agree that it's a whole lot easier to terminate Cat3 on blocks, if it's appropiate for the particular installation.

 
Hi Everyone,

As I read Avaya Novice' response, I was thinking some folks either don't know from lack of knowledge or forget that the circuit characteristics are very different for analog telephone service versus ethernet data transmission and the different anomalies that can and will affect both types of transmissions. In this case the twisting of pairs for analogue causes crosstalk to be cancelled, whether it's 3 feet or 1 inch in relation to the other pairs. The twist causes the signals to cancel one another. So for CAT5/6 or whatever it has NO effect on analogue voice and will not degrade service. That is why there are so few twists in outside plant cables. These cables have been designed with specific characteristics by the manufacturers for the circuits they carry whether it is T1, dialtone, ISDN, DDS, audio, or XDSL(ie ADSL, HDSL, SDSL).

I hope this makes sense. This is why understanding the basics is important in how to apply knowledge to a situation and learning from experience.

....JIM....
 
I've lit up several T1 circuits on 26 guage OSP stuff from the 80's... and suprisingly it worked.

I agree, tommy told the story right -- i remembered it incorrectly.

I still have had problems with properly termianted cat5 twisted pair for dialtone, ill have to think back to what it was.

Oh well. Stick with cat 3 for voice!
 
Stick with cat 3 for voice!

I feel the customer is better served by having at least cat5e in the wall for future applicactions

the cable cost diffrence is negligable


as to the diffaculty of termination it is minimized by practice.

I always strive to give the customer the biggest bang for the buck

getting back to the original question I would pull the cat 6 for the phones
 
As I stated before, If it is a wiring job where there is conduit in the walls, and I'm already running cat5e or whatever for data, then I'm going to run cat3 for voice. I think a lot of people would agree on that one. It has nothing to do with cost, it's just better practice for me -- considering the ease of termination, smaller o.d., etc.
 
One of the great advantages of Cat3 for voice is the ability to use different pairs for multiple phones/faxes/whatever without having to run additional cable. Not a factor on a new installation, where you would just have additional cable runs, but definatly one on a service call for a move/add/change. You just can't snag that brown pair for the credit card machine when it's all Cat5 on patch panels.
 
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