Phone Cable Question

[ccastillo]

This may be a very basic question but I have to ask. Why do some phone cables (base chords that run from the phone to the wall) have one pair (two cables) and others have two pair (four cables). How many pairs are necessary for a phone cable to work? Also can cat5 cable be used as phone cable? Do the colors on each pair make a difference or are they simply there to make sure you terminate the correct pair on each end?

Thank You In Advance......

 

[DigitelD]

It depends on what phone system manufacturer you have. I have seen AT&T systems use all 4 pair. Others have used 3 pair and 2 pair. These are usually analog systems. The newer digital systems use 1 pair. The industry standard is to go in a color code order which is:
white-blue/blue white
white-orange/orange-white
white-green/green-white
white-brown/brown-white
The phone is hooked up usually on the blue pair.
Cat 5 can be used for phone but generally used for data and or VOIP because it is more expensive than Cat3 and Cat3 is all you need.

 

[skip555]

line cords ,flat silver satin , the cords from the phone to the wall use the red/green , black yellow , blue white color code

red green would be line one and be the center two pins

black yellow line ,two , next two out

blue / white line ,three and on the outside

of a 6 conductor plug

most just use the red/green, black yellow

with a 4 conductor plug

what you need depends on the end use , some phones require one pair , some two , some three.

they can also be used to provide dialtone to alolog devices .

no advantage to using cat 5 .

you can use a standard cat 5 patch cord with the att partner sytem as a line cord , but there is no adavantage unless you have extra cords laying around .

we all know you shouldnt be crimping up your own line cords with solid wire cat5e cable right ...
use silver satin stranded .

 

[telnettech]

guys

get off this "dont make your own Cat 5 patch cords" thing...I make cat 5 cables daily and have had no trouble with them at all. Apparently you may doing it incorrectly. a machine is made by a human and is just as likely to make a mistake as a human if not more.

Brian

To error is human.....if the machine doesnt work, then KICK IT !!!!!!!!!!!!!

 

[skip555]

brian

I see failures often of cords made by others , if you are making your own using solid cable the chances of failure down the road are very high , might work fine for you today might work next month but is likley to be a troulbe ticket for me or someone else a year or two down the road .

not a good practice and you are provideng your customer with less then the best .

 

[hawks]

troulble ticket means $$$$... just kidding. We make our own alot also but we do use stranded cable for any patch cable.

 

[SYQUEST]

There have been STANDARDS for patch cords since 2002.

Here is an opinion piece covering that subject you all might find of interest:

http://www.networkcomputing.co.uk/articles/reviews.asp?a_id=68

We have standards for a reason. Making your own patch cords is fine for you, but when the network fails blame your self!!

If it does not meet the Standard, I won't use it.

....JIM....

 

[skip555]

classes like cisco network academy you have to be able to make your own cables ,which gives the new tech the idea that thats the way it should be done

when I took the cisco course the instructor was the head of IT at the local cumminity college he was preaching about how the first thing to look for was the patch cord when there was a problem .

I told them we rarely saw problems with patch cords excpet for obvios abuse and asked if they made their own ..of course ,he says the techs always make what they need on site

I suggested he stock some pre made but he didnt seem impresed with the suggestion.

Besides the standards / quality issue . its cheaper to use pre made than to make your own . by the time you figure the cost of cable , plugs time to cut , crimp and test your up to the cost of a factory cable but with a inferior product

j.Shelton made a great post on the subject in this thread some other good thoughts on the matter

http://www.tek-tips.com/viewthread.cfm?qid=1082060

 

[fs483]

Even though I don't have a big truck fully stocked with networking equipment, I always keep at least 2 pre-made patch cords of differents lenghts (3', 6', 15' and 25'). I also keep a few quality power bars lying around in my trunk. You can make some quick money and fix the problem on the spot without saying : "I'll have to drop by the local computer store pickup some patch cords and of course, I'll be charging my time but not make any markup". You couldn't even make markup if you wanted too when the customer knows that you pickup the cable at BestBuy or something.

 

[telnettech]

i have been making my own cables for 6 years and have not seen any problems with these cables except where i did not make them correctly.....there is no reason that techs that go thru a cable certification course cant make their own cables.....the point is that you have to make it correctly!!!! If not, then you are correct, you will see the network have troubles. Im just saying that "premade" patch cords are not the industry standard and the day that you totally rely on going to a store to buy your cable is the day you cant call yourself a cable tech!!!


Brian

To error is human.....if the machine doesnt work, then KICK IT !!!!!!!!!!!!!

 

[fs483]

Ah but doesn't mean I don't *know* how to make my own cables. I just rather use premade ones which are molded and snagless. I do have the crimpers, spare jacks and boots in case I run out of patch cords. Don't have a field cable molding device though. Also, I don't call myself a cable tech. I'm a IT administrator with cabling knowledge. Anyways, this conversation of make your own patch cable versus using premade cables is getting boring, as it comes up every few months. Oh also, yes I've already got one or 2 bad premade cables.

 

[oldtimerbob]

Your question of how come there are various amounts of pairs are used............

There are a couple of factors to consider:
The time when the cable was installed will determine the type of cable used.
Cat2 was only one pair but could also be bought in other pair counts.
Cat 3 was four pair.
Cat 5 is four pair also.

Any four pair can be used as your cabling solution.

The number of pairs needed for the phones to work is determined by the control device, such as a PBX, etc and what is required by the maker of it.

Most of them today use one pair for the extensions, but some brands such as Panasonice use the organge pair for power and others use three pairs.

Good Luck,

 

[skip555]

cat 3 is /was availible in all pair counts not all cat 3 is 4 pair . 3 pair was pretty much the standard when 3 was introduced

cat 5 is also avilible in pair counts from 2 up to at least 25 , although 4 pair is pretty much the norm.

I dont reacll a cat2 but I do question the one pair standard

the orginal question was as to line cords which are silver satin and I dont beleive they are rated to a catagory , no real reason for them to be anything more than POTS .