atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring "Split" CAT5 wire - 2 pair data / 1 pair telco?

This is the 21st century and apparently that is what Cat5 was originally designed for! Weather you like it not its being done daily and if you know how to install it correctly you can appreciate it. There is 100 pair phone cable behind my house it was installed in 1980 on poles, it has alarm circuits, ADSL, pots lines and what ever the phone company has running through it. Around supper time everybodys phone is ringing and everybody is on the internet and everything is running through that old 100 pair. There is no noise on my line and the Internet is OK. My house is networked on one cat5 since 1998 and it works great and looks great and cost half the price of running two separate networks ...
Touche

OK, you are right about the three pair wiring requirement, but it did use a D8W line cord and an 8P8C connecting block with WECO wiring (A.K.A: 568B). I was close.

Yes, you are close enough.

Way back in the beginning of Structured cabling systems AT&T came out with a 21 pair cable which included 7 groups of 3 pair, each group was wrapped with mylar and then the 7 3-pair groups were formed under the cable sheath. It was meant to terminate on a row of a 110 block using 110C-3 clips. The wiring system didn't last long as far as the market goes, eventually replaced with 4 pair cat 3.

Note to Sam - This was for Thompson McKinon down on the wharf, Forest installed it about 1986 or 87

Thanks Joe. I remember seeing it and scratching my head. Why not 8x3? It filled the blocks better! I was at Lenox Hill Hospital in those days and we had just finished wiring 3,000+ stations - all with 3 pair. We had 2500 sets for the patients,GTE Flashcomm (analog SLT sets with hold and flash) and Eagle electronic Key for Admin. All sitting behind a GTD-4600 CO.

For Data we used the same 3 pair with Baluns for IBM cluster controllers.

From there I went to Irving Trust. Same set up. 3 pair was all we needed. Electronic Key was either ITT or Eagle. Easy to run, easy to term, easy to use. 8 cables on each side of a 66 block. I guess it was around 1988 that we started experimenting with Cat 5 - but just for Data. Voice was still 3 pair Cat 3.

Sam

half price ? cable is the smallest cost in the equation , the labor is roughly the same to pull one or two cables . termination costs ? your still making two terminations using two jacks .

just how much Ethernet is running on that "old 100 pair" ? (we are talking about Ethernet here )

look at the "ugly work thread here , most of that stuff "works great" if you where to ask those that installed it

there is nothing new about the concept , I recall a distributor in the early 90's touting the adapters and stating two Ethernet drops per cat5 cable or Ethernet and phone on one cable

what you do at your own house for yourself or what may be done in a existing situation with no other practical choice is one thing but to advocate and practice non standard compliant new installations as a "cabling pro" is just plain wrong and a poor practice in my opinion

there is a lot of poor , non standard compliant work being "done daily "

Good points. I may have to do this for a customer of mine. They moved into an Old building with existing cable. I am afraid to open the ceiling tiles due to possible Asbestos used. I think I will just use the Brown White off of the data cable for the voice. :db:

Use the blue/white. The brown/white was originally planned as a power pair wwwaaayyy back when 4 pair was recommended by ATT. The Idea was White/blue-voice, White/orange and White/green-data, and White/brown-power.

Four pair just makes sense. Cat5 was purpose designed for extended data transmission but one of its selling points is it is backwards compatible - so to speak. You can wire a whole building with cat5 and then depending on how you break out the ends you can go voice or data or video. More pairs the better. Four pairs just means you can accomodate all the wiring standards, 568A, B, USOC etc plus it gives room to grow. Which BTW is what happened when POE came about. So I would disagree that the design goal was ripping off buyers. Maybe I am naive that the cable industry is devoid of conspiracies but this one doesn't get my spidey sense worked up.

Touché


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