sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Outside Plant OSP Construction Odd Sidekick leakage test result

Not sure if we have any current/former lineman on the forum here, but here goes:

I work for as a contractor for a CLEC and I was dispatched out yesterday to a customer who has POTS & ADSL service with low data rates (like 1-2Mbit downstream). While checking the pair at the NID, I discovered when doing a leakage test (mind you, this is with the CO eqpt disconnected) the Sidekick meter swings to the right like it normally does, but slowly drops left and hangs around 2-4pts leakage. Occasionally it will even jump up a couple of times then fall left to 2-4pts leakage. This happens on the Tip side, Ring side, and Across the pair. It's as if the pair is acting like a capacitor, holding some voltage before releasing it.

Would this be indicative of older paper sheathed cable plant? I haven't seen a test result like this before in the several years I've been doing contract work for the CLEC. The pair other than that odd leakage result, tests clean. Stress is right at 30dB but maintains it. I had to temporarily lift the half ringer to get an accurate kick test: 16 pts tip-ground/ring-ground (8,000ft approximately) and 12 pts across (6,000ft). No left-ins, no other half ringers. No foreign voltage either. No load coils. Aerial drop wire is older plastic covered 19AWG stuff, similar to the rubberized drop wire. DSL is fed from an Adtran TA5000 DSLAM.

I tested from the CO side and defintely see the issue more from the NID/customer side. I tested the IW and didn't find anything wrong. Replaced the modem too. Filters in place.

Since I was unable to find anything wrong for the LEC to fix, we're going to try ordering another pair and see what happens. This location in the past has had numerous issues with varying data rates, up to 5Mbit a few weeks ago, and I seem to remember a couple of years ago up to 7Mbit. We sent out the LEC last week and they reported trouble cleared - corroded conductor.

That test result is indicative of a load coil gone bad or a line extender module with a bad load out L-C bridge. Lead sheathed paper cable will do this if it's wet. The cable should be pressurized and an alarm should have been sounded, by now, if there is a breach in the sheath.

I think you should have the LEC run a test from their point of demarc and see if they have the same issue.

Rcaman

There is no easy and quick way to find the leakage. This is a trouble that requires old-fashioned and tedious labor to locate.

From your description, though, it sounds like it's not wet cable (which would present a steady reading above zero, and not eventually decay) but rather a device, like a load coil, NID with left-in wiring, or a bridged terminal with a left-in drop. The "jumping" you describe could be a wet pair, but I'm leaning towards some device that's doing it. On the other hand, the points that you measure indicate a balanced and open pair, which is a good start.

If you can meet the maintenance splicer in the field, have him open the drop wire, which seems to be one of the things you have not been able to do, as a contractor. I have seen seemingly perfect drop wire exhibit weird problems.

Once the entire pair has been isolated, ask him to go along the route, following the information on the cable plats (diagrams) and open the pair at a mid-point that's convenient.

Then with the pair open at both ends, do the test again. This will eliminate half of the OSP. Then ask him to do it again, cutting the bad half in half again, and so on, until he finds a bad coil, or a branch that is not on the plats, or a left-in drop wire at a bridged terminal. It might even be a deteriorating phenolic faceplate on an old pole- or ground-mounted terminal / cross-box. I've had them act as a resistor, capacitor and even, in one case, a diode, allowing leakage in one direction, but not the other. A quick spray with "instant switchman" and some WD-40 fixed it temporarily. The splicer they send needs to be able to think of all the possibilities.

Can you take a look with a plain old "brown" meter, rather than the Sidekick? I used to love to get involved with these troubles, and found that the old KS meter sometimes gave me a better result than my Sidekick.

Well we sent them out once and they repaired: trouble found - corroded conductor. That's all their ticket description said. I'm not sure they'd even fix the leakage issue.
That sounds like a great way to troubleshoot and I'd like to watch that. Unfortunately the LEC is very difficult to work with. We (the CLEC) are seen as the competition, not a paying customer. We only get access to their field techs for Vendor Meets and occasionally CO techs. Most of these guys I've met have been uncooperative, downright rude, don't care, or aren't trained to fix the issue. The few techs who are really nice guys and know their stuff don't work this particular town.

I may pick up a brown meter. Although fewer and fewer LEC techs have them now.

I'll report back if the new pair exhibits the same issue.

edit: forgot to mention this is an ARDU circuit so it shouldn't have any load coils and only x amount of feet of bridge tap (less than 6,000ft I think).

Shouldn't have and what is actually in the circuit have proven to be a telephone craftsperson worst nightmare. The 1/2 by 1/2 and 1/2 again is an old and proven method of determining a problem like you are experiencing. The problem, as you indicated, is one must have a cooperative LEC tech to work with. I see that here in almost every trouble report. The LEC techs are so few and spread so thin and are constantly being told they aren't doing enough "completes" that they tend to blow off a problem, like yours', because it will take too much time.

In this kind of situation, it would be necessary to escalate this to a foreman and an experienced LEC tech as Arthur explained. Just trying to find a LEC tech that even knows what a plat is will be a challenge. All the examples Arthur mentioned are "real world" problems that OSP craftspersons have been dealing with ever since Alex said "Mr. Watson, come here."

It's not as simple as it once was to trouble shoot this without special help from the LEC. You may not know about pair gain and maybe a SLiC or some other concentrator or device located in the circuit. The plague of having multiple drops on the same circuit with a smart jack or interface module of some sort is a real problem and is quite common.

Rcaman

Make sure the pair that you're talking about isn't "being used for a LARP circuit."

Say that exact phrase to the LEC splicer, and if he nods knowingly, trust him. If his eyes shift to the left, ask for another tech.

And, no, I am not going to tell you what it means. Some things are best left a mystery.

For those of us willing to research a little, would you give a nudge in the right direction? Mr. Google didn't know and I am intrigued. I am willing to do some homework to earn the knowledge.

First hints:

It's easier to pronounce the acronym "LARP" than it is to pronounce the parent acronym "CPMS."

www.airtalk.com/PDFs/Ver27_manuals/27-00s08bsm.pdf

Also, see BSP 201-653-503

CLICK

@ Arthur - Thank you. Interesting reading. ~ Mike