Probe interference 4

[DTSMAN]

I cabled a site today, and the way I do it is terminate all my wall jacks and then tone the wires and do my punch down. At this site the probe went crazy and wouldn't work, neither would my coworkers. Found that if I went out into the partking lot about 50 feet from the building the awful feedback to the probe would go away and as I walked back to the building it progressively got worse until it rendered the probe useless. Any one seen this? Any clues on what caused this? I did make a post a while back that my probe was picking up music and so far that site is running ok, but this sounds worse and I do not know what it is. It is being renovated, the only stereo they had going was a boom-box. I did not see any amps or anything like that. I did see some poor cabling ends for their dish network system.

Bo

Kentucky phone support-
"Mash the Kentrol key and hit scape."

 

[skip555]

Ive never seen anything like that , I use the progressive filter probe wonder if it would have worked there

 

[oldtimerbob]

The problem may have been from the electrical wiring in the house (Romex mabye)? that is un-shielded.

A couple of things you could have done:

1. You could have solved this easily just by labeling all your cables at both ends when you ran them.

2. You could have also shorted out the un-termianted end of the cable's blue pair and put your toner in the terminated end. When you see the light go on (turn it on continuity) that would have been your cable. The toner's plug that goes into the jack will see the center pair (ie the blue).

Good Luck

 

[ISDNman]

Knob and tube wiring acts like this, it will create a hummy sort of noise.

Was this a hum or something else?

Any radio equipment in the building?.

 

[TouchToneTommy]

I have one site that does that - something in the electrical/telephone room causes a LOT of 60Hz interference. A Progressive filter probe helps to cancel it out. If you just go ahead and punch your cables down to the 66 block, then send tone from the jacks. Touching the probe to the 66 pins will tell you which one you've got, and shorting the pair that you're sending tone on will positivly confirm it. Then just number your jacks to match the punchdown.

 

[Bob3470]

Thats the way to number them TouchToneTommy. The other ways waste to much time.

 

[skip555]

thats the way I do it to , I use three seprate tones to save time .

 

[TouchToneTommy]

I agree there. On Cat-5 patchpanels, we use Ideal's Ident-a-lites to trace, label, and test after everything's terminated.

 

[skip555]

Ive got the ideal Ident-a-lite with the two seprate remotes red and green , saves a lot of time

Ive been thinking of making up some adaptors to use it with rjll , and some 66 block clips would have worked well for BOs problem

 

[TouchToneTommy]

Skip - do you find that the bulbs catch on the newer style of Cat-5e and 6 patch panels? I just got done pulling the LEDs out of the plugs with only 2 pins and re-crimping them into regular plugs with all 8 pins.

Also, depending on what you use for testing, I make up a box containing a Seimens STM-8 remote dongle, a couple of AAA batteries, and s DPDT switch. Now the guy running around plugs in the box with the switch in one position to light up the light, then flip the switch to test. A lot less fumbling around.

 

[DTSMAN]

Neither Yahoo nor Google returned anything when I searched for 'ideal Ident-a-lite '. Is there an online catalog someone can point me to, to see this. Thanks.

Bo

Kentucky phone support-
"Mash the Kentrol key and hit scape."

 

[skip555]

BO

heres a link , I think Ideal dropped it but its still made

http://www.snciweb.com/oscommerce2/...id=34&osCsid=88971c0ed82b689771fec20df58c48e6

try a google search for DATALITE

I bought mine on ebay for around 60.00

Tommy
Yes I have had that problem a few times ,I've just been carefull since and kinda lift up as I remove them , your solution of re crimping sounds good I'll give it a try

 

[wires]

At this site the probe went crazy and wouldn't work, neither would my coworkers."

I have had that problem with coworkers before, not working.

The noise (interference) is from a fairly powerful RF source that is most likely powered by the building's electric service. If the probe has a volume control turn it down and try to locate the area where the noise is the loudest. You could try a AM radio and see if you hear the same sort of noise. Once you find the area where the noise is the loudest use the breaker panel and see if the noise is related to one (or more) circuits. The only reason to bother with finding the noise is that there could be something VERY wrong with the building wiring.



<rant mode on>

This sounds like a lot of walking and trouble because of sloppy work. There is NO EXCUSE not to label cables when they are pulled.

At some point someone is going to need a floorplan that shows what wall jack is connected to which patchpanel position. Hopefully the building owner handed you the drawing when you agreed on the locations of the wall jacks. If not, even the most challenged should be able to make a workable drawing in less than 30 minutes for an install with less than 50 wall jacks.

It's simple. Number the wall boxes on the drawing. Put your cable reels near the patch panel location. Pull cables to the first wall box. If there is more than 1 cable for that wall box tape the cables together at the patch panel end (white or yellow tape is good). Cut and label the cable(s) at the patch panel end (or both ends if you want). It is NOT HARD.

If you have more than 1 cable per wall box and you don't have different color cables then put on the wall box jacks but wait to put them in the wall plate until you have terminated the patch panel and are ready to test the cable. While testing insert the wall box jacks into the correct positions in the wall plate and label the wall plate. This way you will have a 100% orderly, tested and labeled install. You will only have to go to each wall plate 3 times. Pull, terminate, test/label. I would guess that the toner method involves at least 4 trips and at least a few errors. Time is money.

It is 2006. Toners and probes (the Tempo 200FP is the way to go) are still useful for fixing problems. You should not have this sort of problem on a job where you pulled the cables.

<rant mode off>

 

[skip555]

done it both ways I find it a lot more effeciant to pull then tone and mark I think its also more acurate .

was at a new site today , replace a bad jack

faceplate marked 2

wire had a label on it 2

20 min later I discovred that it was actully 5 , not 2

so marking the cable dosn,t alwys ensure accuracy somebody misread a 2 and a 5

had they been pucnhed down and then toned I suspect they would have been properly labled .

This sounds like a lot of walking and trouble because of sloppy work. There is NO EXCUSE not to label cables when they are pulled.

you like to label anyone who dosn't do it your way as substandard and less than competant dont you

 

[wires]

so marking the cable dosn,t alwys ensure accuracy somebody misread a 2 and a 5".

Obviously the install was not tested. I bet you will find more wrong at that site than one bad jack.

Toning IS NOT testing. Not doing at least a continuity test on all 8 conductors at each jack (Microscanner or a $60 8 LED unit) is cheating your customer.


"you like to label anyone who dosn't do it your way as substandard and less than competant dont you "

Who likes to label? Certainly not me. Labeling is a PITA but it is less painful than burning up time running around with a toner.

The issue is that to execute a orderly job on any thing but the most trivial install drawings are necessary. Once you are working from drawings then a numbering scheme is needed. The problem with pull and tone jobs is that there is seldom any order to the patch panel and in some jobs not all the wall jacks get terminated to the patch panel because they were "missed". A simple numbering system avoids these problems.

I have done jobs both ways. Marking the wires takes almost no additional time. If I am running 8 or fewer jacks I can always use the ID kit on my Microscanner. The last thing I would ever consider charging a customer for is running around with a toner on a job where I pulled the cables and didn't take the extra 10 seconds per bundle to label them.

How much time could you possibly save?

 

[DTSMAN]

Ahhh,,,,Yea...

Moving right along, any other ideas on what could render a tone and probe totally useless no matter what the volume level is.

FYI, for future reference, I do proprietary cabling for proprietary systems that consist of serial, vga, network, and other misc. cables that apply to our systems. I do not cable for anyone else but the systems my company sells and we have our procedures layed out for what works best for us and the environments we are in (which are not office environments). I am always up for advice and constructive criticism but I am far from sloppy or unprofessional in what I do.

Bo

Kentucky phone support-
"Mash the Kentrol key and hit scape."

 

[wires]

any other ideas on what could render a tone and probe totally useless no matter what the volume level is"

The volume control is almost useless at "tuning out" interference. It is used to determine relative signal strength.

Any fairly powerful low frequency signal can be picked up by a probe. 60Hz electrical wiring is an example and the reason why a filtered probe is desirable. Sometimes AM radio can be picked up.

What does the audio from the probe sound like? Is it a buzz a constant tone or something else?

What sort of building/business?

Did you try turning off the electrical service?

What sort of lighting? Any big neon or other discharge fixtures?

RFID?


"we have our procedures layed out for what works best for us and the environments we are in"

Obviously your procedures failed. If this problem delayed your finishing this job by more than the few minutes it takes to label a bunch of wires then you need to review your procedures.

 

[TouchToneTommy]

It's not the few seconds that labeling takes, it's the HOURS that sorting the cables and trying to comb them into neat bundles at the patch panel that takes.

I know you don't agree with this method, BUT, bring the bundles of cables out on the ladder, down to the rack, and start terminating at number 1 on the patch panel. Continue until you run out of cable. The patch panels are ALWAYS in numerical order, starting with number 1 in the upper left hand corner, and going up to whatever the highest number is.

Now a runner with a walkie talkie, a power source for the LIGHTED ID set (NOT A TONER) lights up the jack, now you know the number, and swaps in the testing dongle while he prints the label. You're doing the testing while he's doing the labeling, and then runs to the next jack.

We ID/Test/Label 300 runs in about an hour and a half.

If you add additional runs later, they just go after the last existing port on the patch panel. It doesn't blow an entire numbering scheme based on floor/room/jack/port. It just gets the next number.

A simple spreadsheet can sort the jack numbers by room numbers and jack/port. Sort it both ways, and leave it on site (and with the IT person as a file).





Now as far as the interference problem, try using a butt set, set on monitor, grounding one clip and running the other clip down the block to look for tone. Also, some tracers have terminals for a butt set, which cuts off the internal speaker, and might make it easier to find the subject cable. Try putting your toner on split pairs at the jack side, which will give you a "stronger" tone on the cable, might make it easier to overcome all the other noise.

 

[ISDNman]

BTW, one possible reason for all the hum (if indeed it is hum not some other type of interference) could be that the electircal system is improperly installed and that the ground and neutral are not tied together at the service entrance (or that the ground wire is damaged).

This is a case where this *migth* come back to bite you in terms of equipment reliability.

In a acase liek this if I owned a clamp-on ground resitance meter I would check the telecom ground and if that we not good I'd check the main electrical ground.

Note, I would not mess with the electrical equipment, but if there was no ground or the ground resistance were high I'd stop all work until it was fixed.

Yes, the aabove is sort of off topic, but somethign to consider since if the electrical ground were bad it is going to affect other systems too, causing reliability probelm in the long run and possible personnel safety issues too.

 

[phuzzy42]

ISDNman is correct, plus the customer is going to come back to you if his expensive LAN equipment is fried because the grounding is bad - even if your grounding connections are correct, you've still wasted your time proving it wasn't your fault.