atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's 2 T-1's

I have a customer that is moving their system and service to a new location. They were originally going to move their service from a PRI and Data T-1 to a fractionalized Product. Now the carrier is not able to get the new product in on time so they are going to move their existing service to the new location until they can get the new product in (just a few weeks). So my question is can I extend both of the circuits on a single cable? I know I should have prepared a little bit better cabling wise, but the customer is on the cheap. I can definitely pull some more cable and charge them, I just thought I would ask here first.

I have heard different opinions, went to look at a Data circuit for a marina the other day and the customer told me that AT&T said that two circuits shouldn't even be on the same binder. (I didn't hear it myself) just what the customer told me.

What is the official ruling?

Each T1 should have its own cable. We try to run T1's in different binders, or offset the transmit & receive several pairs apart in the same binder.

I agree. Each T1 should have it's own cable and be clearly tagged as well ESPECIALLY in the case of multiple circuits. I also make sure my tags are bright and easy to see. Lastly, we also make sure the dmarc is clearly identified and punchdowns are marked as T1 circuits so some guy doesn't try finding dial tone on one.

As for running cable, my rule of thumb is if you have to run one cable, run two and have a spare just in case. If you ever needed to rule out an extension as a problem you could swap the cable and be done.

Fred

Thanks guys, I kind of thought that would be the case, just wanted to run it by others first. I appreciate the feedback.

J

When Lightpath wired my R&D office, they specified tothe wiring contractor 2 25-pair cables to the office. Mind you, we were only ordering 4 POTS lines. But the contractor (who was the owner and his wife, because the first two times the company showed up the kids they sent did it wrong twice!) told me that Lightpath specs them this way for all orders, so that if T-1's are ever ordered, they terminate the transmits on one CABLE and the recieves on the other!

I support Lightpath's specs to an extent. If you were to extend T circuits from a DSX Patch Panel in one room, to a corresponding patch panel being installed in a separate room (or building, etc.), the wiring & cabling installed between each point of failure should support separation of all receive and transmit pairs; providing them across separate 25-pair cables, to eliminate any interference. Lightpaths' policy obviously applies to all of their work, regardless of the amount of circuits being provided to their customers.

Wow that's expensive eh? 2 25 pair runs for 4 pots lines with the "hopes" for future T1 orders.

Not that I can pick on Lightpath. I've heard nothing but good things about them and Cablevision provides my blazingly fast Internet at home.

Wow that's expensive eh? 2 25 pair runs for 4 pots lines with the "hopes" for future T1 orders.

Yeah, Lightpath uses CAT5 25 pair too.

Cablevision provides my blazingly fast Internet at home.

Blazingly fast? Until the kids come home from school around here.


-Hal

So, let me get this staight, the T-1 can come in via the Telco 2200-pair cable for several miles, but you have to seperate the transmit and recieves for the last 100 feet?

Larry, We recently extended numerous T1s from one DSX Patch Panel to an extended/corresponding panel in another room using 25 pair cables between the 2 DSX panels. Our panels are built to provide all transmit sides of all the T1 circuits across one or more cables, and all receive sides of the same T1 circuits across separate cables, to eliminate any interference. If T1s must be within in the same binder, we try to provide separation (using vacant pairs) between the T1s' receive and transmit pairs.

I just stumbled across this thread and it looks like I finally found someone who knows what they're doing. I'm in a similar situation:

I'm bringing in 10 (eventually) point-to-point T1 circuits along with a PRI. The demarc is a couple floors down, so my idea was to use traditional cat5e patch panels at either end and use two 25-pair runs, one for tx and one rx. I'm coming from the data side with no real telephony experience. Is this the right idea?

You can use this approach, but I'd run multiple CAT5e four pair cables and split the tx/rx between them. Eleven circuits, even only half of them running under the same cable sheath might be setting you up for a lifetime of NTF's. To keep it clean, you could probably get away with individual cable runs without splitting the circuits up as long as the run isn't too far.

I'd also advise against using standard patch panels in favor of using the proper RJ48X jacks so that maintenance operations will keep the circuit looped.

Thanks for the quick reply.

So, if we were talking about 4 T1's, I could use two CAT5e cables, with the 4 TX pairs on one, and the 4 RX pairs on the other? That would be useful since I have plenty of CAT5e to spare.

Is the DSX patch panel mentioned earlier the RJ48X type you're referring to?

Thanks again!

We always run 2 shielded (Cat 3) cables - one for xmits and one for receives and have never had any problems.

Cat 5 ought to work fine though, if you don't have shielded cable. But, as Ed said, keep the xmits and receives separate.
Sam

JKB:

Yes, you should be fine with that approach, and yes, a DSX patch panel will be be perfect.