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I'm learning how to make my own Ethernet cables (to get deep understanding of Cisco for their exams), but the cables I am getting have small wires whose colors I cannot distinguish.

A person in my organization who is expert at making Ethernet cables insists he can see the colors as they are. Is this another case of what color is that dress? Seriously.

Really, I am so stumped right now, and I've seen two CAT5 cables like this, where the colors are faded and indistinguishable.

How can I create my own Ethernet cables when I cannot figure out the faded color of these wires? Is it that the cables are too old and the colors get faded over time? Is there another solution. I really wish to create Ethernet cables.

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UPDATE:

I stripped more of the cabling. What is supposed to be brown/white is plain white, and the rest of the white/color combos are plain faded

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UPDATE II

On the cable it is printed:

0100 FEET CAT-5e General Cable L CMP (UL) C(UL) 4PR 24AWG GENSPEED 5000 PLENUIM --- VERIFIED (UL) CAT-5e--- 03-03 100537J1 CAT-5e

UPDATE III

Here are wires from another cable, printed:

BERK-TEK HYPER-PLUS 24 AWG CMP C(UL) US ETL VERIFIED TIA0568-C.2 CAT 5E & ISO/IEC 11801 CAT 5 26100016 FT

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    If you strip the cable down further, you will see that there are 4 pairs of wires -- each pair is twisted together. That might help.
    – Ron Trunk
    Apr 24, 2015 at 13:42
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    Hard to tell. It could be faded, or the manufacturer ran out of ink, or a manufacturing problem.
    – Ron Trunk
    Apr 24, 2015 at 13:57
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    Color striping on Cat cables is always blotchy. Having faced the exact issue many times in the past, I start by just holding it a little farther from my eyes and thinking to myself "which one (of R/G/Bl/Br) is least likely to be one of the others?". After that? Punt. As a noob you will crimp a lot of ends that just don't work, for reasons other than the color. Just keep getting practice and the color sorting will become more natural to you. Exactly how flush each wire is to the end of the plug, and how far in the plug the jacket goes will become important and the colors will come naturally.
    – Jeff Meden
    Apr 24, 2015 at 14:45
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    After Update2: when you strip off more of the jacket it's hopefully clear how they are paired. Also, stop untwisting them! Only untwist what you need to get the wire straight into the guide on the connector. It will be easier to keep track of and you will get better crosstalk resistance.
    – Jeff Meden
    Apr 24, 2015 at 14:54
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    After update3: that's a great example of how every cable maker does it a bit different, so you need to resort to the pairing and "which one looks least like another" method since clearly there is no real standard for how a solid vs striped color will look. Berk-Tek clearly just grabbed some clear plastic (pvc?) coated cable for Blue/Green and then added in some opaque pairs (PET plastic?) with little regard for consistency.
    – Jeff Meden
    Apr 24, 2015 at 15:19

3 Answers 3

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The colors are just there as an ease-of-use tool. What really matters from a functional standpoint is what cable is connected in the jack in what position. Electrically the colors of the wires make no difference. It will require care, but you can identify the wires per pair by "ringing" them out with a multi-meter with a continutiy check ( the symbol looks like an arrow pointing at a vertical line or a plus sign ).

https://learn.sparkfun.com/tutorials/how-to-use-a-multimeter/continuity

Pick a pair and check with test leads on the meter to match them up (holding both ends of the cable together, put one test lead on one wire and one test lead on the other end, testing each wire in turn until you get a reading).

It's a little bit more work, but you can identify a each wire this way and place them in the appropriate postion.

Two issues with my original post addressed pointed out by comments below: You must keep the pairs in the proper relationship to one another and conforming to wiring standards and good practice.

@Ron has pointed out this answer was unclear (Thanks!). It's VITALLY important to keep the pairs together as per standard.

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The reason this is so important is because using a pair of wires twisted together to carry a signal utilizes the electrical properties of the wire to improve signal strength, reduce attenuation and destructive interference - it's a great trick to make crosstalk work to our advantage! ( http://en.wikipedia.org/wiki/Twisted_pair )

The difference between CAT5 and CAT3 is the number of twists per inch ( three vs. five, unsurprisingly ). CAT3 is not rated for speeds over 10Mbps and as a result is mostly seen as legacy POTS/PBX cable, whereas CAT5 is rated up to 100Mbps ( and years ago replaced CAT3 for pretty much all uses ). CAT5e has a plastic core that keeps the pairs twisted evenly in the cable related to one another and is rated up to 1000Mbps. ( @YLearn pointed out this is not the case -- CAT5e and CAT6 do NOT require a spline, however some manufacturers used this as a strategy in production of cables ) You can see that the same basic electrical wiring sees an order of magnitude performance improvement just based increasing the twist of each pair and another order of magnitude based on the way the pairs are twisted together.

Another poster ( @Jordan Head ) correctly pointed out that while this is a great learning exercise or as an emergency short-term production fix, it's very important to follow standards - no one wants to have to troubleshoot random wiring pinouts in the middle of the night when there is an outage. It's an added difficulty that should be avoided in production environments.

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    It's vitally important that you keep the pairs together. It's not just 8 wires, it's four twisted pairs of wires.
    – Ron Trunk
    Apr 24, 2015 at 13:55
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    It's also pretty awful practice to not use the standards (T568-A / T568-B) in a production environment. So if you think about it, colors do matter from a functional standpoint. I know what you're getting at, it's just something important to keep in mind. Apr 24, 2015 at 14:25
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    True, but colorblind technicians need love too. If you can see the colors it's not hard to check a pinout. It would drive me crazy as well, but the OP did state that this was essentially a learning exercise. He's asking how to proceed using scrap cable for practice. In that respect, it's good practice learning to be flexible and adapt to the situation you're in. Sooner or later you're going to walk into a closet that's been cabled by someone with no love for standards and learning to think outside the box early on will help. Apr 24, 2015 at 14:31
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    While technically you can test each wire, doing so will brutally slow you down to the point where IMHO you shouldn't consider ever making your own patch cables, and instead buy them premade. And this comes from the guy who insists on changing his own oil to save about $20 every 6 months.
    – Jeff Meden
    Apr 24, 2015 at 14:50
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    Actually, there is an electrical difference, albeit small. Each of the 4 pairs have a different level of twist in them -- limits harmonic distortion. (find an EE to explain it)
    – Ricky
    Apr 24, 2015 at 19:11
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Maybe it is the dress thing, but I can make out the four solid colored wires; orange, green, blue and brown. As you work with cables from different manufacturers, you will find that not all things are the same. Some will have colors that look a bit more "faded" or even somewhat "translucent."

From there, you need to identify the white/color wires. While most manufacturers do indeed "stripe" the wire in some way, it is not at all uncommon for them to use just a white wire and it is identified by the solid colored wire to which it is twisted.

In this particular case, it appeaers there is a white/orange mark as well, so I would presume the the other white wires also have markings. However, the marks could have significant spacing, so you would probably want to strip back more of the outer jacket to expose more of the internal wires.

As to whether this is fading or something else, but significant fading typically doesn't occur unless exposed to sunlight, chemicals or some other factor. It is more likely this is just how it was manufactured, but no one could answer that without knowing the manufacturer, product number and possibly manufacturer date or lot number.

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I know its an old post.

But I'm colour blind - so have had this issue trying to sort green from brown. I now use the number of twists green has 65 twists per m and brown 51 twists - so it is easy to tell the difference, simply by looking at the twisted pairs :)

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