ETHERNET CABLES.. are all the cores used?

[apostolakisl]

And Lou - if you were to just wire a jack with pairs that don't fit the standard, like just going pair by pair (orange white/orange, blue white/blue, green white/green, brown white/brown - for example) - my Fluke tester will fail the cable - it does matter, even at shorter distances - those twists are very important. As others said above, the standard has origins in Telecom so the ethernet standard was designed around this in the way that takes advantage of the twisted pairs. If you're making a 10ft patch cable it'll probably work - maybe not at gigabit; but if you're doing a 100ft run it will fail.

I am going to give this a try this weekend. I have a 60 ft patch cable and can easily pop a couple keystone jacks on the ends and swap the wires around any way I want.

Anyone care to take bets on how it will work? I'm betting it will work fine so long as twisted pairs are maintained, but perhaps be more susceptible to noise from nearby wires (which I won't really be testing) on gigabit mode.

 

[Del91574]

I am going to give this a try this weekend. I have a 60 ft patch cable and can easily pop a couple keystone jacks on the ends and swap the wires around any way I want.
Anyone care to take bets on how it will work? I'm betting it will work fine so long as twisted pairs are maintained, but perhaps be more susceptible to noise from nearby wires (which I won't really be testing) on gigabit mode.

Dig out the TDR and Pentascanner, as that's the only way you'll really see what's going on.

I've got a nice Megger TDR and I can usually pick out where a cable is stapled with it.

 

[wuench]

You can run out of spec, if there are issues it will show up as physical errors, usually CRCs. And even those can be tolerated to a certain extent. So even if it fails a scanner certification, you may be ok to run. And if errors occur they usually get worse at higher speeds or more bandwidth utilization.

I mean what these guys are saying are all best practice so it's a good idea. But I sold my Fluke years ago and just do a quick wiremap on my home stuff these days. And the tester I use is so old it only checks 3 pairs...

 

[tmbrown97]

This is one place I'll sound like DELInstallations... while it may work, it won't be right - and I don't want callbacks or time wasted troubleshooting a problem that just can't be tested without the right tools.

The single most valuable tool I own for finding and/or preventing problems is my Fluke cable qualifier - it saves me so much time dealing with crappy cables or bad terminations - it's the very first tool I break out when troubleshooting any network issues... and I never install a single piece of Cat5 without qualifying it. Too many issues early on as a result of poorly run cables that are just damn-near impossible to troubleshoot without one.

I can almost guarantee that, even if that cable works, my fluke would never qualify it - and as such I'd never use it.

 

[ecborgoyn]

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