atcomsystems.ca/forum Forums TDM Business Telephone Systems Avaya - Lucent Telephones & Systems Outside Cable Plant help!

(Moved here from Outside Plant since it's more of an Avaya-specific situation)

Where to start...I am an experienced cabler but am new to OSP. I consulted several experienced cablers on this project. I have run 1100' of 6 pair Superior Essex CAT 3 22 AWG in 1" Sched. 40 Conduit with 2 pull boxes. I have Circa 2606's on each end and IROB's behind those (LUC-146E). I have grounded the primary protection with 6 AWG at both ends (far end to the ground rod and near end to building steel and grounded the aluminum sheild with 3M 4460's to the second ground lug on the Circa primary protection devices with 12 AWG. This is for one Avaya Definity 6408 digital phone. The problem is the phone won't come up. I get around 47.6V on a multimeter at the far end of the run and the phone seems to try to come up but will not fully come up. When I first installed the primary protection (the IROBs hadn't come in yet) I was able to get the phone up but with heavy static only at the far end. When I put the IROBs in today I now cannot even get the phone up. HELP..I've read all the other posts that looked like they related but have not found any advice that I haven't already tried with the exception of testing the resistance of the ground. I have even tried using another port on the Definity. Any help would be much appreciated and seeing as how I'm into this job for about $1000 bucks would sleep better if I can get it completed!! THANKS!

Let me add some more detail. There are a couple more legs to this circuit. From the remote building the OSP cable is just shy of 1100'. It then transitions to about 100' of CAT 5. Then onto a 25 pair back to the phone room, about 350'. The phone works where cross connected to the CAT 5 (so at about 450') but when taken to the end of the OSP cable it's a no go..

I had the same thing happen with a Rolm switch (9000). We buried about a half-mile of 400 pair to feed a new building, but used 24 gauge since "industry standard" was all that was specified in the bid specs.

Phones worked like a charm right there at the cable head in the new building, but the minute we added a typical cable run, they died. We replaced the far-reaching station cables with 22 gauge and LUCKILY, everything worked out. Talk about cutting it close.

Sounds like you are in the same predicament. That CAT5 concerns me since it adds unneccesary conductor length to the cirucit. Any reason why you ran CAT5? It's not better for voice, in fact it adds a bunch of length to a cable run.

Why, oh why oh why does everyone think that CAT5 or higher is better? Using it when not required takes away valuable distance allowances. Think about it: Tighter twists=more length. Going from CAT3 to CAT5 alone adds about a half-inch of copper circuit per inch of cable!

It worked (kinda) without the IROBs because the IROBs have series resistance. Put those in and that was the straw that broke the camel's back.

Seems to me that you have a voltage drop problem but you say that you measure 47.6v at the far end with the phone connected? That's not bad considering the battery is 48v I believe. Simple enough to check though- leave the phone connected at the far end then take voltage measurements at your cross connect points going back towards the PBX. For reference, what is the voltage across the pair with a phone right at the system?

If it does turn out to be voltage drop, yes I would get rid of that CAT5 then I would combine 2 pairs of that 1100' run. Seems you only use 1 pair of the 6.

Another possibility is the wrong clamping voltage on the protectors you are using and possibly even the IROBs. What are Circa 2606's, what comcode or number are the IROBs?

-Hal

Gee, some of you guys stay up LATE or get up EARLY!
EV's comment about 'hidden' length is very well put. CAT 5 25 pair is available, but since each pair must twist at a different rate, the 25th pair, if straightened out, is TWICE the length of the original cable. I got bit by that when someone wanted several 10-base-T's and phones in the same place and a CAT5 25 pair seemed like a good idea. WRONG! We almost broke even on that one.
And, are not just IROB's adequate? Chances are, if they won't prevent THOR damage, more arrestors aren't going to help. John C.

What is the max distance for a Definity? Adding up the lengths you listed, you're at about 1550 feet.

In putting the CAT5 in the middle, which I'm sure is 24 gauge, you've reduce everything to 24 gauge. Just like water in a pipe, you can feed it with a 4 inch line reduce it to 2 in the middle and back out 4, but you'll still only get a 2 inch pipe worth of flow. Current works the same way. Double up your pair like Hal said, at least through the CAT5 and see if that helps. I don't know the range of these phones, you may have to double up the 22 gauge also and triple up the CAT5. Better yet would be to replace the CAT5 again as Hal stated. To see if clamping is causing this you could strap out all your protectors.

OK, the 100' of CAT 5 was already there and the circuit goes like this...Definity with 25 pair tails to 66 block....jumped over to CAT 3 25 pair going about 350' to another IDF 110 block...CAT 5 punched down to 110 block and running about 100' to the head of the outside cable...The primary protection are Circa 2606QC/QC with gas fuses 3B1E 350V (I did read in another post that I should us 75V fuses and can change those out on Monday). I cannot get rid of the primary or secondary protection. The primary is Code and AVaya will not honor the warranty without the secondary. I looked up the distance on a digital phone can go on an IP Office (I do not have access to the definity docs) and they can go up to 1000 meters and the Definity should be comparable so at 1500 feet this shouldn't even be breathing hard...Lastly, I'll check the voltage when I get there this morning. I had planned on doing that anyways but a very good idea...thanks for all the suggestions and

I was saying thanks for all the suggestions and I'll keep you all posted...

One other note. I have tried taking the IROBs out of the equation with no luck...