atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's New T1 installation question

Dave... that's not a NID that I’ve touched. I found the image on the web, it just shows an outdoor NID with a Smart-Jack built into the enclosure. Around here, outdoor NID’s with Smart-Jacks built into them have a thick door unit where the actual circuitry is housed. I just wanted to make sure that’s what the OP was talking about and not just a standard NID.

Thanks to all you guys. I have learned alot since I posted my un-informed question earlier..lol. you guys rock. I will verify in the morning that it does indeed have the smart jack built in.

You'll notice that the outdoor NID houses 2 circuits, but has 4 jack/plug/terminal sets.

There are 2 sets for each circuit. The top one is wired RJ-48C, using 1&2 and 4&5. The bottom one is wired RJ-48S, using 1&2 and 7&8.

An inside mount 2-slot NID has a slide switch inside to change the jack wiring.

I gtoofed on the above message! My question is this: What would happen if we used CAT5e to extend a T1 circuit about 250' from the Outside Smartjack? I have a pending installation which calls for just that. They already have one T1 that is being fed by a section of 4/24 CAT3 UTP(with one POTS line and one ISDN BRI line as well)..........and they have constant problems on it, but it was installed like that some time ago.

Since you'll be on the customer side of the interface, your best bet for this run would be to use two separate C5e cables, one containing the transmit pair and the other containing the receive. In a perfect world, I'd suggest two-pair, 22 gauge T1 cable where each pair is individually shielded under a common outer jacket.

Cable capacitance over a distance of 250 feet might be enough to cause problems that you can't explain. Once you get beyond about 150 feet, it becomes a finger-pointing festival.

Thank you very much! Do you have any idea locally where we could find the two pair 22 gauge T1 cable in the Hagerstown MD area, since that is where the install is taking place? Other than that would CAT 6 help with the distance factor any?

Quick addendum to the above post. I have found some online suppliers for the 2/22 T1 cable that we might be able to order a rush shipment from, depending on the end user and clients' wishes, which often translate into dollars more so than anything else(penny wise and pound foolish at times).

So another quick question: can we place several T1 circuit sides under the same sheath if they decide to go the separate CAT5e/CAT6 route, i.e. the transmit sides under one heath and the receives sides under the other sheath?

Thanks!

I'd check with CSC in Clarksburg, MD (301-353-1150) for the cable.

As for your second question: Yes, you can place all of the transmits under one cable sheath and the receives in the other. That is done quite often.

Ed said:
Just wire the distant jack at the router as 568B and connect the white/blue of your cable to the red/green terminals. Connect the white/orange to black/yellow pairs as shown in the above pic. As long as the cable run is under 100 feet or so, there will be no issues.

I'm a T1 newbie, about to wire up from my new NIS (same as above) to a T1 DSU/CSU. Based on the pinout of a 586b plug on the router end, I would have wired in the NIS as:
Yellow (CT1) --> Orange (pin2)
Black (CR1) --> Orange/White (pin1)
Red (CT) --> Blue (pin4)
Green (CR) --> Blue/White (pin5)

The picture and Ed's comment seem to have the pair colors reversed, pin1 as CT1, etc. Where am I going wrong?