atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's Can a noob do inside wiring for T1?

Probably just a matter of choice. The shorting bars provide a loopback when the plug is removed. Some people may not want that.

Is it just me or does 1.544 Mbps make you think of dial up compared to 15Mbps that even the cable company will give you now for less than $30 a month? (Of course that's when the kids aren't home from school.)

-Hal

I am about to extend a private T1 line from my Asterisk PBX, located in the basement of my house, to a channel bank in my barn. I will be using two pairs in a 6-pair BSW. The distance is about 200 feet.

I am pondering the above quote, and wonder why that advice is being offered, when T1 lines are often sent from a CO to a subscriber's premises over miles of Cat-nuttin', in regular subscriber OSP.

Perhaps you can explain it to me?

Arthur -

It's been my experience that when the Phone Company sends a T-1 from the CO on copper they send the transmits and receives on at least different binders if not different cables.

Sam

I am trying to understand how we are supposed to fit a pair from two separate shielded cables into a single plug and not have it look kludgy. Also, what do we do with the extra pairs? Also, it seems that connectors 7 and 8 are supposed to be used for grounding. When the Telco terminates it's T1 into an RJ-48X jack, does it usually ground connectors 7 and 8? If we use shielded cable, how do we go about connecting the shielding as well as wires 7 and 8 to connectors 7 and 8 in the modular plug? Can we use ordinary 8p8c modular plugs for T1?

You don't put a plug on it. You terminate it on an RJ48X and then use a short (standard) patch cord to connect it to the equipment.

I've never seen positions 7&8 grounded.

Trim back the shields and tape the end of the cable.

Again - Don't put a plug on the cable.

Sam

Well, the proper way is to terminate both cables on a split block, then run a patch cable with solid wires and punch them down to the appropriate pairs on that same block. There are 2,3,4 and 6 pair split blocks that are perfect for this application. Obviously with outdoor installations, the block will need to be contained within some kind of proper weatherproof enclosure, like an AT&T B-CSC, C-CSC or D-CSC.

Honestly, with regard to the grounding of pins 7/8, I've never really checked. I seriously doubt that anybody even worries about that anymore. I know for sure that on indoor installations, Verizon never does anything with pins 7/8.

Shielded cable includes a drain wire. The drain wires from each cable should be joined together at the block and connected to a suitable ground connection. It is usually easiest to punch these drain wires down on the bottom two rows of clips on the block and just bridge them together. That way, a single pair jumper wire can be used to make the final connection to a suitable ground.

Many of today's outdoor T1 network interfaces include both screw/IDC terminals and an RJ48X jack per circuit. That way, you still have the option to terminate separate cable pairs with minimal effort. These also include a CPE grounding terminal in them to accommodate the drain wires.

Yes, a standard 8P8C plug will work just fine for this application.

Oops! I forgot the original point of the thread that the NID was outside. I would hope that the Telco would bring the demarc inside. There are no weatherproof RJ-48X jacks that I know of.

I guess if there's no room in the outdoor enclosure for another jack and a cord then you've got no choice but to put a head on the cables.

It would be a pretty crappy install on the part of the phone company to force you into that situation. I would complain if they stuck you with that.

Sam

Sam:

They now have T1 network interfaces that look like a "pregnant" standard outdoor NID. Inside the cover is all of the electronic gear in a sealed compartment. They then have the left side for the telco incoming connection to the protectors and the right side for CPE terminations. They are very common in these parts since labor is kept to a minimum for the Verizon installers.

During the miles of cat-nuttin', it might very well be carried on a single pair... so there's no reason to care. Once it comes inside, and becomes 2 pair. Then the longer those two pairs are in contact, the more distorted the signals will get, and Cat5 is actually the worst, because after the twists, 10 feet of cable is at least 12 feet of wire.

I know this because my customers often use any standard Cat5 cable to connect between their smart jacks and my dialers, and sometimes a cross over between the dialer and channel banks or other equipment. They can usually get away with it, as long as the distances are short... like a standard 2m patch cable (6 feet).

But then there was this one customer whose IT department was at odds with the communications department, and tried to put the dialer in the server room, while their PBX was in the phone room. Both rooms were quite sizable, so the cable they used was a 50 foot Cat5e patch cord. They wondered why the recordings they were doing were so scrambled.... We didn't realize this cabling issue immediately, of course. First we tried replacing the hardware, and swapping ports on their switch. The best part was when the tech who ran the cable, said in his whiny voice, "But we used Cat5e - the best there is!" Great for a 350Mhz signal... not so great for a 1.5Mhz signal

My recommendation of 10-15 feet, is from some testing I did. I cut Cat5 cable to lengths of 5, 10, 15, 20, 25, and 30 feet. I punched them down to a jack on each end (crossed over) connected to two different Dialogic T1 cards using 3 foot Cat3 patch cords (additional 6 feet). Then played an audio file from one end, and recorded it on the other. I could definitely notice the distortion on the 20 foot cable... it was probably tolerable to someone not listening for it, though. But audio distortion is one thing... the OP's data T1 won't like it much.

I don't think 200 feet is going to work so well for you....

Hi all. They went ahead and scheduled the install while I am out of town. My representative told me that I don't need to be home. Here is the quote from the representative....

"If the LEC has access to the MPOE it is not necessary for you to be there."

I guess that means they will install the jack on my side of the NID and I will be able to extend it inside when I get home. Should I expect it to work or is there normally another step after that?

Thanks!