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I am a systems administrator by trade. Though I have done a few wiring jobs, this is not a task that I claim to be a professional at, either by training or experience.

However, ethernet wiring isn't something that I've ever thought of as difficult. There is a handful of best-practices, and bad-practices. You watch out for those, and a basic wiring job should be smooth and successful.

Recently, my employer hired a contractor to do the wiring for a new branch. This contractor did a couple things that were high on my "do not do" list. Before I bring these items to my employer's attention, I'd like to have some formal specs or quotes from certified specialists regarding these items. Possibly I'm wrong, and they're not a problem at all. Please weigh in.

All cable and components are CAT6 rated, and the drops should not need anything beyond 1-gigabit + PoE.

  1. For many of the drops, he left 1" or more space between the plenum and the jack. The pairs are mostly twisted up to the jacks, but sometimes they are untwisted further than is necessary. My concern is signal loss. I would like information to back that up.
  2. Most of the drops do not have wall-plates to their jacks. My concern is that it will allow the jacks to be moved around, possibly degrading the jack's contact with the drop cables.
  3. For many of the drops, instead of a straight-run from the network stack to the destination, he terminated in a jack above the ceiling, then used a patch cable to link to another run, and repeated at the destination. So, many runs, there are actually three separate lengths of box cable connected by a pair of patch cables.

My first concern is signal loss. My second concern is that, with time, environmental factors will degrade the quality of the connection between the jacks and the patch cables.

Again, I'm looking for written specs that support my belief that these are bad practices for wiring. Although I appreciate the anecdotal support, that is not something that I can bring to my employer.

If you feel that I am wrong about any of these concerns, I would appreciate your saying so, and backing it up with specs that support you. I am open to being wrong.

Thanks

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    #3 is an absolute no-no. I would not pay this quack, bill him for the removal of his mess, and then hire a competent data cabling installer. – Ricky Beam Jun 23 '16 at 20:42
  • @ltwally - You are on point and I will try to find some docs to support what you've already correctly determined to be inadequate attention to the basics when I have more time. Post a couple pics of the problem areas if you're able to, particularly above-ceiling terminations and excessively untwisted pairs. – Ted Quanstrom Jun 23 '16 at 21:14
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    The ANSI/TIA/EIA 568 Commercial Building Telecommunications Cabling Standard is what you want cable installers to abide by. There are also other standards, e.g. NFPA-70, the National Electric code, which must be adhered to. A cable installer should also test each cable to meet the test suite for the cable category, and he should provide you with the test results, which you should keep for future reference. – Ron Maupin Jun 23 '16 at 23:14
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    That standard document actually costs money, and you can't get it on Google. What you got on Google paraphrases the real standard. What you are looking for is horizontal cabling. You are only allowed, except in the case of a MUTOA (special case for modular furniture), to break the cable at a cross-connect panel. Inline splices are not allowed. – Ron Maupin Jun 27 '16 at 22:22
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    "Topology The horizontal distribution system must follow a star topology. • The telecommunications outlet/connector in the work area is to be directly connected to a horizontal crossconnect in a telecommunications room located on the same floor as the work area • Bridged taps and splices are not permitted." – Ron Maupin Jun 27 '16 at 22:30
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Sounds like a definite mess.

The solution is quite easy really: have an independent certifier check the installation, take the measurement protocols and hit the installer square on the head. There's no way this will pass.

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The standard I think you want is ANSI/TIA-568.2-D but its predecessor, TIA/EIA-568 is easier to find information on. The Wikipedia page for TIA 568 has a Topology section which may be useful for a stepping off point when researching the infrastructure wiring concern in point #3.

Also, while not an "official" document, this Leviton Cat6a reference guide details "best practices" and may be a useful easy to read reference.

For point #1 see p73 bullet 5 and p74-79 for termination details.

Point #2 is addressed in an implied manner throughout the document.

For your point #3, P20 somewhat addresses the concept of "consolidation points" and p38 implies the "home run" best practice.

Additionally, if you have the funds to contract for an independent tester to test the lines that will probably be enough to reject the work on but only really will fail based on points 1 and 3. #2 is just plain shoddy work.

In the future, I would recommend you draft a standards document that you make all bidders sign and if they dont adhere to it you dont pay them. Alternatively, including this in the RFP works well. If you search you will find many examples of this online and can craft verbiage appropriate to your situation fairly easily.

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