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Previously, we had a 6RU comms cabinet near the ceiling.

We've now replaced this with a full-depth server rack sitting on the ground.

The plan was to remove the old patch panel, and punch it down into a new patch panel in the server rack.

However, it turns out the old cabling didn't have any service loops - so it's basically already stretched taut, and not long enough to reach the ground (approximately 2m too short).

What are our options here?

  1. Use some kind of inline RJ-45 coupler. This will also require crimping 8P8C modular plugs onto the end of the cable.
  2. Punch down a CAT6 keystone jack onto the end of each cable (48 or so), then run a patch-lead down to the server-rack.
  3. Mount a small wall-frame on the wall, leave the old patch panels in place, and run patch leads
  4. Re-running all the cabling.

What do people think?

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  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can provide and accept your own answer.
    – Ron Maupin ♦
    Commented Dec 15, 2019 at 1:13

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The answer is to run a new cable, and make sure that there is a minimum 10' service loop on each end. There should also be a pull string, but if there isn't, you can use the old cable for a pull string, but be sure to also pull a new pull string, too.

Per the ANSI/TIA/EIA 568, Commercial Building Telecommunication Standard, splices, taps, couplers, etc., are not allowed. Doing something like that will create an impedance mismatch, and the cable will not pass the test suite for the cable category.

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  • Isn't there already a possibility of impedance mismatch from the patch cord into the patch panel to the source cable?
    – Arian Faurtosh
    Commented Jan 2, 2021 at 21:29
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If you want to maintain Cat6 specs, pull new cables. (But I'd bet none of your existing cables are, in fact, compliant -- almost no one actually tests cable installation; if they didn't give you a printed report (actually notebook with 48 drops), they weren't tested.)

Otherwise, any of those options will get the job done. Just stay away from "telco crimps" (those fancy gel filled things telco techs use) to splice the extensions on. IMO, leave the existing patch panel in place and use long patch cords would be the easiest route.

"The worst cable in the world is one that's one inch too short."

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  • Thanks for confirming my bias. I just ran into this problem today, while finishing up a move to my company's new office - now I have two CAT6 cables to APs that are your a few inches short of reaching the switch. And yes, I probably should have stood behind the contractors' back with a telescoping baton as they were running my cables...
    – Zalán Meggyesi
    Commented Mar 26, 2021 at 22:23

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