sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's t1 with DMarc Install

I am trying to fnd some info on this. I have been searching on here and a few other sites and a lot on Google.com and have not found really anything worth while. I need to figure out how to do this as I have a pretty decent ammount of install experience with this type of teleco type of stuff but just not a t1 with dmarc.

any ideas???

Not sure what exactly you are asking...What are you trying to do?

well i am basically saying i have a lot of low voltage cabling expereince but nothing with a t1 and dmarc.....i need some direction in to read up on and do a install for....

Really the only thing we as installers have to do for a T1 is to run a cable from the smartjack to the phone system or router.
The telco puts the smartjack and circuit cards in, and it is their responsibility to provide functionality to that point.
Some of our T1 experts will likely chime in soon.

You talking about what type cabling to run? What pins are used? The DEMARC is the Smartjack.

Extending a T-l DMARC:
---> Run data cable from T1 smart jack to where T1 needs to be (you can also extend by using 2 regular feed pairs but to start you off easy just file that in your notes)

---> Terminate cable on 8 conductor box jack near phone system or router & label with T1 circuit number

---> If Smart jack is modular, crimp a stright thru rj-45 end and plug into smart jack

---> Your T1 is extended and all you need is a straight thru patch cord or t1 crossover cable to patch the t1 to your equipment.

Lots of juice flows thru a T1 circuit which is why I terminate the extended end 1st.

The simple explanation for using feed pairs is to make connections straight thru and use pins 1 & 2 and 4 & 5 on both ends (smartjack RJ-45 and 8 conductor box jack).

Good luck...

so if i was going to help out my buddy do this the phone company who is Bullseye, would already have everything there i just simply would only need to run some cat 5e from the 50 pin "smart jack" to where ever he has his router? he is also getting VOIP from Bullseye....i have done pleanty of POTS and rj45 stuff just not really any of this Bullseye t1 stuff.... a bit lost...or I guess I should say I feel lost.

also any suggestions on how to test? i have a cable tester and a tone generator......i am mostly hoping to find some resources to look up to how setup and install a T1......i can punch the cables i would hope and I can run the cable i am just not sure about some of the in-between stuff as far as testing the D50's and so on?????

any sites i can go to get some good reference? :confused:

The term "RJ45" is 1980's terminology, but I think that I understand what you mean. An RJ45 can never support a T1 or PRI circuit. You are speaking of 8P/8C plugs and jacks, right? In essence, all that you need is a two cable pairs rated at CAT1 or better for a run up to 166 feet. If the run is longer, then go ahead and run a CAT5 or better for each circuit to play it safe.

As previously mentioned, a T1 or PRI circuit only uses pins 1,2,4 and 5 on the plug or jack to provide a transmit and receive path. Other pairs are not necessary. The jack at the far end should be equipped with shorting bars to provide loopback when the hardware is not connected (RJ48 wiring pattern) in order to keep the circuit alive if testing is necessary.

Chances are, you can get away with a simple CAT5e cable run, terminated either 568A or B wiring patterns. They must be the same at both ends.

Here are some reference links to give you some insight into the difference between an RJ45 and RJ48 wiring patterns.

RJ48 Wiring diagram

RJ45 Wiring diagram

Here's another link to most other jack wiring diagrams:

Other USOC Wiring patterns in general

so with a T1 is each line on a seperate circuit?? I think I am mostly confusing myself more then anything....i am just nervious about doing this for my buddy and being totally lost and just standing there with a dumb look on my face...

A T1 circuit is 24 channels on one physical line. It is all digital so you just see a 2 pair connection.
The '50 pin' you speak of would be the Telco Demarc. They would take 2 pairs off of that and connect the smartjack. This is a metal enclosure with a T1 card in it. The bottom of the smartjack has an RJ48X jack on it. That is where you connect to.

No, the smartjack has an 8p8c as was stated before. If you have a 25 pair (50 pin) connector what you have is a channel bank beyond the T-1 interface.

EDIT: Think of it as 24 POTS lines.

ok....lets hope i am not confusing myself......thanks for all of the input......cross your fingers for me as i am going tomorrow to do this.

Good luck...

1. Do you know if "Bullseye" has installed a smartjack or a channel bank?

2. If possible, throw up some cameraphone pics of the Demarc and link 'em, that will answer a lot of questions.

3. Good luck!

FYI.

In Verizon service areas, and possibly AT&T and Quest, the Westell mounting used with T1 & DDS circuit installations have a slide switch that configures a selectable RJ48C or RJ48S interface on the built in eight pin modular jacks provided.

RJ48C DS1 services on pins: 1-2 (CPE RX) & 4-5 (CPE TX)

RJ48S All DDS rates on pins: 1-2 (CPE TX) & 7-8 (CPE RX)

To keep it simple. Run a cat5 with A or B jacks on each end. Plug in a patch cable from your jack to the telco smart jack, it should be tagged or on a card in the unit with your companies name and the circuit number.(this is also the number the phone company usues) This is all telco to that jack. On the other end you will need a crossover or patch depending on the equipment. But at the end jack you have put in, you have extended the demarc from the telco to the equipment and they will need the same cord as if they were plugged directly into smartjk. You are just making one long cord. PS a $60 set of data wire testers will make you look like a pro and save you alot of trouble. .Practice with a patch cord. That's what a good wire will look like.