Which fiber should I install in a new building?

Scarlet

Member
Jul 29, 2019
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That is factually incorrect.
How can this be incorrect? My contractor presented me a choice of cables, one was AWG 23 (labelled CAT.7) and one was AWG 22 (labelled CAT.7A). I chose the AWG 22 cable because larger diameter means less heat dissipation. I made this choice because I want to install PoE+ devices on some of the outlets connected with this cable. The Keystones terminating the Cables will be CAT.6A anyway.

I will probably try using 10GBase-T at some point, but most devices will be 1GBase-T.
 

jabuzzard

New Member
Mar 22, 2021
22
8
3
How can this be incorrect? My contractor presented me a choice of cables, one was AWG 23 (labelled CAT.7) and one was AWG 22 (labelled CAT.7A). I chose the AWG 22 cable because larger diameter means less heat dissipation. I made this choice because I want to install PoE+ devices on some of the outlets connected with this cable. The Keystones terminating the Cables will be CAT.6A anyway.

I will probably try using 10GBase-T at some point, but most devices will be 1GBase-T.
Because the question was what's the difference between Cat6a and basically Cat7 and upwards. The statements was the difference is just the thickness of the copper. That is just plain wrong.

Like I said anything better than Cat6a has each pair individually screened. The cable is electrically a bundle of four miniature twinax cables; a coax cable with two cores. This is electrically completely difference from balanced pair cables which everything up to Cat6a is. Unless you are terminating these with end to end properly, so effectively CG45 as Terra connectors are not remotely compatible with anything then by using Cat7a cable you have made things worse, probably much worse than had you stuck with Cat6a.

It's a hard lesson but you have be ignorant or wilfully stupid to actually install anything better than Cat6a. Higher is not always better and in the case of Cat7 and up actually worse. We could do with an EEVblog video on why this is the case.
 

klui

Active Member
Feb 3, 2019
431
181
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I've honestly never considered F/UTP, S/FTP cables. My Cat6 cables are 23AWG purchased around 10 years ago, rated to 550 MHz printed on its sheath. It has a twisted spline separating the 4 pairs. If you're concerned about having the correct conductor size for PoH you can get Cat6a in 23 AWG. Looks like there aren't any Cat6a in 22 AWG.

Ask for a sample of the cable to see how each pair are shielded. Worse case get some bulk cables yourself and have your contractor run them. You can choose to terminate.
 

klui

Active Member
Feb 3, 2019
431
181
43
I am confused by your nomenclature of patch cord "A to A; A to B." Methods describe both ends. So I take "A to A" straight through/method A; "A to B" meaning universal/method B.
I was looking at more information and the A to A, A to B commonly describes duplex patch cables. MPO/MTP use methods A, B, and C but methods A and B could use the term A-to-A, and A-to-B, respectively.

Unveil Polarity of MTP/MPO Multi-Fiber Cable Solutions - Fiber Optic Cabling Solutions at "Two Polarity of Traditional Duplex Patch Cable"

How to Ensure MTP/MPO Polarity of the Patch Cable Right? describes common ways to connect cassettes.
 

Scarlet

Member
Jul 29, 2019
74
24
8
The copper runs are already done, all in conduit (mandatory for ethernet and coaxial cabling here), so I can rerun them if needed. I made the contractor use as few bends as possible and no sharp bends on the conduit so I actually have a chance of rerunning cables through the conduit.

All rooms have at least one copper/ethernet run in conduit, most rooms have two copper/ethernet runs and one coaxial/tv run in conduit.
 
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