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I'm educating myself on how to terminate Cat 6a cables. I've seen some articles talk about "grounding" requirements because of the "shielding" in the cables. But is grounding a concern if I'm just connecting two devices directly?

If I have a spool of Cat6a cable and I crimp on my own RJ45 shielded connectors, and then I use this cable to connect a router and a switch (for example), do I need to care about grounding? I'm not going through a wall jack. The two devices would be connected directly together.

Apologies if I'm misusing terminology and making this question unclear or confusing.

2 Answers 2

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Category-6a cabling is UTP (Unshielded Twisted Pair) cabling. If your cable has a shield, it is something else. Any shielded cable must be properly grounded. That requires connectors and equipment that properly ground the shield, at least on both ends. Improperly-grounded, shielded cable will be a problem because the shield will exacerbate the problems it is meant to prevent.


If you really want to learn how to do this correctly, you will need to get (buy or rent) a very expensive cable tester to see if what you terminate actually passes the Category-6a test suite. Building Category-6a patch cables is something I have never seen even experienced installers be able to do and get it to pass the test suite. I have only seen factory built patch cords be able to pass the test suite for Category-6 and Category-6a.

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  • The connectors I have are these: RJ45 Cat 6A Shielded Modular Plugs amazon.com/Cable-Matters-50-Pack-Shielded-Modular/dp/B00E4OCOUW (So, doesn't this mean they are indeed shielded and therefore require grounding?)
    – Stoop
    May 23, 2017 at 18:17
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    If it is shielded, it is not really Category-6a. There is a lot of mislabeling and crap sold for cabling. ANSI/TIA/EIA specify the cabling categories, including Category-6a, and have not, and will not, certify any shielded cabling. ISO/IEC certifies cable classes, some of which use shielded cable. For example, ISO/IEC Class F, which some people incorrectly call Category-7, but there really is no such thing as Category-7, is shielded cable. If your cable is shielded, you must use shielded connectors, but unshielded cable requires unshielded connectors.
    – Ron Maupin
    May 23, 2017 at 18:24
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    Ok, I think I'm understanding a little more, and I think I may have been wrong about having a shielded cable. The cable I have is Cat6a F/UTP. If I understand correctly, this actually is NOT shielded. It is only foil-screened. So I need to make sure I use unshieled connectors, and I don't need to care about grounding, correct?
    – Stoop
    May 23, 2017 at 18:43
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    Foil-screened is shielded cable. The manufacturer is taking liberties with the cable classification. The shield is there to make up for weakness in the cable manufacture in that it could not pass the Category-6a tests without it. It must be properly grounded, but it is not actually Category-6a cabling, which, by definition, is unshielded. Not properly grounding the shield will cause the cable to perform worse than if it has no shield at all, neither fo which will pass the test suite.
    – Ron Maupin
    May 23, 2017 at 18:47
  • Ah ok. Thanks. I'm scrapping my shielded stuff and just going to get unshielded. Did some more research and found that, for residential use, shielded isn't even necessary. Thanks for the discussion.
    – Stoop
    May 23, 2017 at 18:53
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Only one and a noise shield is permitted to be connected to building ground, and it should be as close to the building grounding rods as possible. If it is grounded to more than one ground source, say each end of a cable or multiple grounds over a network circuit, ground loops carry building differential currents and stray fields. Grounding one end only creates a protective Faraday cage shielding the wires and equipment within from EMFS.

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  • That was true in the old days, but modern networking frequencies require grounding at more than one end. "Whether this ground is at one end or both ends of the cable run depends on the frequency at which a given application is running. For high-frequency signals, an STP cabling system must be grounded, at minimum, at both ends of the cable run, and it must be continuous. A shield grounded at only one end is not effective against magnetic-field interference."
    – Ron Maupin
    Jan 8, 2020 at 6:13

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