atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring combing the cables

I have alsways tried to keep bundles of cables nicely combed (I believe that is the correct term). However I've seen some opinions that this is not such a good idea. Something like having all the cables parallel to each other will increase crosstalk. Does this ring true? I've seen pictures of installs where the cables are laid out in a cable tray in a very casual fashion, kinda of swerving, crossing over each other. Not tangled, but not neatly side by side. Not sure how one would do that without a tray or ladder.

Richard

Here is an example of what I am called combed.

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What you don't want are the snug bundles of cables with nylon ties every two feet for the entire length of the run. You can still lay things out nice and neat at the rack or back board since this is only a small section of the overall cable run.

From a data transmission perspective, messy is good, while perfect parallel installation is bad as it is more susceptible to crosstalk - especially at higher frequencies. We've tried to find middle-ground - less bundles and less 'perfect' dressing.
Mike

That is true crosstalk is and issue. But on a good note you now have an excuse to sell more hardware and not be as "neat" as it should be. The best part is you can get the job done much faster LOL

I agree with the consensus... tight "cigarette packing" is "so 90s."

With the advent of higher frequency transmission, ala 10GbE, a more natural bundling is preferred. It doesn't have to look sloppy, but neither should it look too manicured.

The biggest challenge I find on this is convincing the end-user. They are so accustomed to seeing these ultra-combed bundles that they decide "I want that." It takes a little convincing to get them to understand the performance ramifications they can encounter down the line.

Bundle size is also something that is changing...

looks are not as important as cable performance.
i hope that isn't cat6. no ty wraps. velcro.

I hate Velcro and it looks unprofessional. Looks like a CG did it and if they like it naturally I don't.

Ty-raps are fine as long as you don't snug them up. Matter of fact in a plenum ceiling I use tie wire loosely wrapped around the bundle then tied off to a support.

If you understand the simple concept that whatever you support or hold the cable with cannot distort any of it you will be fine.

-Hal

I only use Ty-raps when they are needed. Hook and loop is so much easier to add cables too. I find installers are too lazy to cut and add a new ty-wrap instead they add another ty-wrap, next thing you know you have 50 ty-wraps in a 2 foot span.
J-hooks or similar should be used instead of "tie wire", tie wire does not provide enough area of support for the cable causing it to have too much of a "kink"

The tie-wire is to keep the bundle in the J-hooks as well as to keep the bundle together, same purpose as ty-wraps. The "support" mentioned is the J-hook.

I know they make Velcro that is plenum rated but I would not feel comfortable using it. If the next guy is too lazy to cut off the ty-raps well, that's his and the customer's problem, not mine. Nothing says he'll undo all the Velcro either. The nice thing about tie-wire (the way I do it) is that it can be removed and reused like Velcro.

Now that I'm thinking about it I don't know if the inspectors would give Velcro a thumbs up in a plenum ceiling even if plenum rated. They like to see either red ty-raps ($$$) or tie-wire, nothing plastic.

-Hal

Hal, what is tie wire?

Hal, if you don't mind, I will answer Jeff's question.

Jeff, it's approximately 16 gauge steel wire. It isn't galvanized, just plain old steel wire. It's frequently used for bundling MC, AC and BX cables together and other miscellaneous electrical bundling or support tasks.

Thanks Ed. So where were you in chat tonight?

I don't know how people feel about BICSI here but the new EIA/TIA standards for Cat 6 actually say to absolutely NOT comb Cat 6 due to increased crosstalk. I don't think it is as much an issue with Cat 5 and 5E.

By the way EIA/TIA also advises against using tie wire or any thin support due to the weight of cables possibly causing cable twist malformation much the same way as too tight ty-raps. The recommendation is to use "J"-hooks or some other wide base support.

Just my .02 worth

I'm a BICSI member and RCDD. What is it you are asking with reference to BICSI?

I, too, am a BICSI member. I have seen very few references to BICSI here and some of the responses and advice given seems to be contrary to EIA/TIA. Since I am new here I guess I was unsure if some here may not like BICSI (as is the case with some of the local sparky's and even some small interconnects in my area). Unfortunately some of the "old timers" think "Aww that ain't necessary. I don't do it that way and I have never had any problems". So I guess, since I am new to this board, I was just treading lightly so as not to start any negative arguments about BICSI standards, which by the way I do always try to adhere to.

You are right, Bill. There are plenty of folks here who fail to see how a group of manufacturers seeking to sell more expensive cable, equipment and design standards really have a handle on things. I admit to being one of those "Aww that ain't necessary" guys.

The only advice contrary to BICSI standards you will see here will be remarks made by seasoned professionals. These are persons with decades of experience in the industry. These are also the people who can troubleshoot a problem without a ten-thousand dollar tester. They are NOT people posessing a simple certificate attained through a sponsorship by cable manufacturers.

I speak from experience after having owned my telecommunicactions company since 1983. I maintain very strict Bell System standards with my company's installations. THOSE are the REAL standards. BICSI and TIA/EIA came into play decades after the tried and true Bell System specifications for wiring. "568B" was Bell's standard in the early 1970's when these "authorities" were simply seeds in the ground. This standard was hijacked and simply given a new name. Period.

I have made attempts to jump on every certification bandwagon that rolled through, but I got tired of it. It's all about marketing. Haven't you figured that out? These certifications of wiring and hardware are simply meant to scare you into selling whatever the manufacturers want you to scare your customers into buying!

I challenge you or anyone to devise a better set of plans than the ones developed by the Bell System for anything. This company employed many of the "Aww" guys that you will find here. They represent the most knowledgable people on this forum.

One simple question: A $2.00 "J" hook every four feet versus a web in building trusses at no cost. Tell me why?

I was afraid my "old timers" comment would come across as offensive and I should not have said it. I appologize to anyone I may have offended by those remarks I certainly did not mean to imply that anyone here is not professional.

I would have to respectfully point out that the Bell System standards from the early '70's did not and could not anticipate the technological advances and high speed data demands of today's data cabling.

When I first got into the business in the early '80's I was trained by a retired Bell Systems guy and to this day I value that training and the knowledge he passed on.

As for why "J"-hooks instead of bar joists, it is my understanding that (as I said in my earlier post) the thin edge of a bar joist or similar support combined with the weight of the cables will over time cause cable malformation resulting in potentially slower data speeds or even transmission failures.

If you want to argue the validity of those claims you will have to argue them with someone with much more technical knowledge than me. I only offered my advice based on my belief in the BICSI - EIA/TIA standards and my own personal experiences installing high speed data cabling. By the way I too can troubleshoot a cable without a $10,000.00 tester but I don't think either one of us could tell how fast the data is capable of traveling down that cable without one, therefore I own one and use it regularly to ensure the cabling installation will perform its purpose. My goal, as I am sure yours is also, is to give the customer the best cabling installation I can utilizing any reasonable tool I can to make it better. In my humble opinion the BICSI TIA/EIA standards are just another tool.

I also understand that manufacturer certifications are often not worth the paper they are printed on in terms of quality of installation. However, many of my customers who are not so knowledgeable have been hijacked by these manufacturers and require that I have it to install their cabling, so I do. I also am of the mind that I can always learn something new and those certification classes have sometimes taught me a thing or two.

By the way BICSI and EIA/TIA are not manufacturers and their standards are not based on scare tactics to make people buy their cabling. They are created by engineers with much more knowledge than I have to ensure the data transmitted has the best chance of reaching the desired speeds. I did not write them I just happen to agree with them.

BICSI was founded by "Bell Systems" people in the early '70's and I imagine many of them would take offense at the notion that they just "wanted to scare people into buying something" or were just "seeking to sell more expensive cable, equipment and design standards".

Again, I am sorry. I never meant to offend anyone hence my original comment "I don't know how people feel about BICSI here but....".

This is precisely the kind of disagreement I was trying to avoid.

My apologies also for hijacking this thread.

I agree wholeheartedly with TTSI1.

Telecommunications has changed tremendously since the "Bell days." I understand the sentiment of some on this board, but I think it is unfounded.

Technology is an ever-changing issue and we must learn to change with it if we want to be the best that we can be. BICSI and TIA standards exist to ensure optimum performance. Bell standards were designed for voice communications, which can be run on high-grade barbed wire

High performance copper and fiber cable play by a new set of rules. Those rules are codified in TIA, and BICSI be extension, standards.

Regarding the J-hook question... TTSI1 is correct in that the wide-based saddle is necessary to permanently support and evenly distribute the weight of high performance cabling without performance degredation. As cable technology advances and bandwidth increases this becomes more and more of an issue.

TIA isn't in the business of selling J-Hooks. TIA and BICSI develop standards and then manufacturers design products that will comply with those standards. That is the relationship between the standards bodies and the manufacturers. It isn't some grand conspiracy to sell products.

The manufacturer certs aren't worth much at all. Those are more for the manufacturer to control who is installing their product on large projects that the manufacturer will be required to write an extended warranty against. There has to be some level of control over the quality of work that the manufacturer is guaranteeing for 25+ years. Thus, the mfgs require that contractors be certified for any projects that they are required to guarantee with their own pockets. That sounds fair and reasonable to me.

My presence on this board is simply to answer questions and offer advice based upon my education and experience. I think that if you review my record of responses you will find that they are sound and have been given in a respectful and professional manner.

I enjoy contributing to this board and appreciate everyone who takes time out of their day to come here and contribute. That's what makes this industry great.

Hans

Bill and Hans:

I am very impressed by both of your responses. It's pretty obvious that you both are very passionate about your trade. For this reason, my hat is off to you. Thank you very much for your input and participation on this board.

Having been trained to Bell standards while working for IBT I have to agree with you. It works and it's reliable.

On a side note:When I started I was trained by guys with 30+yrs of doing it the "right way". They took their time and everything was dead to spec. Now it's all about Good Jobs in 8 and shotgunning pairs to get it working.Within the phone companies themselves the Old Bell way of doing things is being replaced with "make it work for now". So maybe BISCI and organizations like them will become more useful as time progresses.

Have you heard of millipede ties? How well do they work? I havent pushed them on my techs, but they look like a cool concept because of the reuse of them and not a cheesey as velcro

I got some samples of them, but don't really like them. Not sure of the cost but I would think it is a lot more expensive than a standard nylon tie.