atcomsystems.ca/forum Forums General General Telephone & Systems Information Demarc Cut, Proper Reinstallation Help

you would probably be best served by getting someone knowledgeable in outside plant to help

ok Ive got to ask why would you use a "Greenlee Volt detector" ?

If you don't know the color code, do as Skip says and get someone who does. Will the phone company at least tell you what pair it's on? Is there a phone number associated with the SDSL?

Speed 94. That nice little protector you see has a tail terminated on it at the factory. You can order what you want, but let's just say it comes with a 30 foot tail already terminated into the box. Now the cable guy comes in with a splice tool and lays out the wires from the tail into one half of the connector and the outside cable into the other half and crimps it together.
Instant 25 pair connection. He does it 4 times and it's 100 pairs.

Sometimes the building entrance terminal has only the tail from the protectors to the panel on the side. The installer still splices the entrance cable into the box the same way.

The 3M MS2 4000 series connectors are about 4" x 1/2" and take up less space than any single pair splices you could ever use.

110, if it was truly underground cable at the demarc, you're going to need more than meters and butt sets. There are only 10 colors in underground cable. The quickest way to find the pairs is to strip the cable back more and find them. Next quickest is to tone them out from another location. Last resort is to try to reconstruct the pairs with a butt set. Split pairs will still give you dial tone, so it's pretty self defeating.

Carl

resolved. but thanks for the help fellas.

answer: CO coughed up the binder info which was 15. connected modem and it linked.

the GC who had the demarc removed wants me to keep it spliced so the site can function but I don't know the code. Is there a legal issue here? GC says "at this point I dont care for the phone company." If I keep it connected (grounded and surge arrest included) will I hold liablity? CO will be out to work the cut demarc issue. Should I disconnect and walk away from this project or should I do what I'm paid from the GC?

Carl, I did not know that about underground cable. How are there only 10 colors?

Ten basic colors it's the combinations that make the pairs

Gee, I show up late and the post I had prepared (but not sent) is now yesterday's news! To answer your question, incoming feeder cables are not always spliced anymore. You are probably referring to service in Bell Operating territory, where an intentional "weak link" was placed in the cable before it terminates. This is referred to as a fusible link.

Usually, this involves a terminal that comes with a factory-equipped cable stub. Most companies make these with 25 foot stub cables which work just about anywhere. This factory stub cable consists of 26 gauge conductors. Since most outside plant cable is 24, 22 or even as large as 19 gauge, this means that the stub cable is much less capable of carrying high currents.

During a typical lightning strike, the surge is instantaneous and the normal gas-tube protectors catch them. If a power line crosses a telephone cable, the high voltage condition will last much longer. This results in a fire hazard since the gas tubes will react by shorting the pair to ground. The pair then heats up and can burn. Of course, it is hoped that this condition will be contained and all that will be lost is a protected terminal instead of the building.

By installing this intentional weak link, if a power cross occurrs, the pair or pairs in the cable stub will burn out. The stub cable is fire retardant, so any flameout will be contained within it's jacket. The only inconvenience would be failed cable pairs. The fire risk is minimized.

If you take a close look at any of these installations that have spliced incoming feeder cables, you'll probably see a label on the stub cable from the terminal that's exactly two feet from the point where it enters. It will likely say "fusible link; do not cut shorter than two feet". This is because it has been determined that two feet of 26 gauge wire is sufficient to provide the fusible link.

Some other entrance terminals have two feet of 26 gauge cable built-inside so that the incoming cable can be terminated or spliced directly inside the enclosure. These are much more common lately since they can be stacked and save a lot of time on splicing operations.

Lastly, many telcos try to plan in advance for expansion. Although a building's current subscriber requirement may be for only 300 pairs, they will bring in a 600 pair cable. By bringing this cable into a splice case, the unused pairs can be safely contained without the expense of having to install terminals to terminate them. These things cost thousands of dollars per hundred pairs.

You won't see this as much these days since fiber is commonly used for larger installations. They don't need to plan as much for copper expansion.

Unlike switchboard cable (inside wire etc), outside cable uses solid colors. If you lose the twists, you're out of luck. in 25 pairs you have 5 sets of 10 colors.

110, don't be silly. The GC is paying you to keep it working, so do it. Unless you get some butthole installer they should understand.

Carl

Jeff, I just go to thinking, I bought the Siemon MT-5000 (25 pair tester) and a set of shoes to fit 66 and 110 blocks for that friggin' UT job.

If memory serves me, I don't think I got much change back from $600...the shoes alone were about $100 each for the 110 block ones.

That was almost 13 years ago and I don't think I have used them since LOL

Carl

You did the UT job 13 years ago?