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I've run (or had sub-contracters run for me) literally thousands of cables, some of them through electrically noisy places like plant rooms and never had any problem with unshielded UTP.
If you do use shielded, it complicates matters because you have to earth all the shielding for it to work properly. Some suggest it can makes things worse if you don't.
As I understand it, the "thing" about running UTP parallel to supply cables is about preventing the "shock hazzard" whereby the mains induces high voltages and currents in the UTP rather than there being some interference issue with data transmission. Symbol to symbol, I can't help thinking 50Hz mains is going to be pretty much DC for ethernet pulsing at 125,000,000Hz. The twists in UTP (it's what the "T" stands for) is what does the bulk of the work rejecting interference. Ethernet also uses "balanced" transmission which also rejects lots of induced interference.
Anecdotally, my sparkies have sometimes run mains and UTP alongside each other in dado trunking and we never had any issues. I believe the guidance is to try and cross mains at 90 degrees if you can and restrict any parallel running as much as you can and maintain some distance if possible. There are some electrical engineers and professional cable installers who read these columns, so they may give you the full skinny if you want more detail (or I've got any of this wrong.)
I wouldn't even bother with cat6, but since it's now little more expensive than cat5e, one "might as well" for a small job where honing down the cost isn't an issue.
As I am fond of saying, to actually be cat whatever, one has to observe all the installation stipulations (for example, higher cats require the use of proper "containment" - no zip tying it to the water pipes or clipping it to the wall, the cable must be "laid" in a not "pulled," etc. etc.) and the install needs to be tested with some rather expensive certification equipment which most DIY'res don't bother with. There's much more to it than buying cat whatever cable and bits and bobs.
However, that doesn't mean it won't "work" for ethernet - ethernet signalling is well within the performance headroom and one has to do a spectacularly bad job for it to not work. Poor termination is usually the worst culprit. Just be careful not to kink, crush or knot the cable when installing it and ensure any direction changes are "curved" and not bent into sharp angles. If you buy higher cat cable, the wire gauge it thicker, so you need to ensure your patch panel, faceplates, etc. match.
If you've got a fair few to do, a punch down tool and a cheap cable tester might be worthwhile. The 10 pound cable tester jobies don't do any of the "proper" cat tests and sometimes miss things like split and crossed pairs, but they might save you some head scratching. You can always punt them on afterwards. |
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2-12-2019 04:58:12
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