First time terminating ethernet cable

Discussion in 'Accessories' started by vette-kid, Feb 10, 2018.

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  1. vette-kid

    vette-kid Young grasshopper

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    What did I do wrong? I'm using cat 6 solid copper cmr riser rated cable. I copied the sequence from some premade patch cables that are known to work. With my cable, the camera powers on and the nvr trios to detect it and even sees it in poe management, but it will not fully detect it, no image. Camera works with premade cable, so it must be my cable. But it obviously works to some degree as the camera is getting power. Where do I look?

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  2. fenderman

    fenderman Staff Member

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    Use the 568B standard.
     
  3. awsum140

    awsum140 Getting the hang of it

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  4. vette-kid

    vette-kid Young grasshopper

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    OK, you guys were right (you already knew that! ). Why does the camera care what color the jacket is? As long as both ends are the same I would think it would not matter. Are the different colors somehow different beyond color?

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  5. awsum140

    awsum140 Getting the hang of it

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    Transmit and receive data, and the polarity of the signal, are on specific pairs and colors within those pairs. The same is true of PoE power. It doesn't matter if it's a camera, phone or simple ethernet connection.
     
  6. fenderman

    fenderman Staff Member

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    They are twisted in a specific order to prevent cross talk and interference
     
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  7. awsum140

    awsum140 Getting the hang of it

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    The reality is that the colors don't really matter other than to conform to spec and keep it simple. What does matter is the "pairing", pins 1&2 being a pair, pins 3&6 being a pair, pins 4&5 being a pair and pins 7&8 being a pair. Of course, the same pair has to be on the same pins on both ends for it to work. If you interchange wires from pairs, say all the white/color on pins 1-4 and color/white on pins 5-8, then crosstalk will go sky high and dropped packets will kill things rather quickly.
     
  8. tangent

    tangent Known around here

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    Another common mistake is crimping the cable when the wires aren't fully inserted into the rj-45 plug.
     
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  9. awsum140

    awsum140 Getting the hang of it

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    And the difference between getting a good connection and no connection can be hard to see. That's why a simple tester is such a handy thing to have when making cables.
     
  10. vette-kid

    vette-kid Young grasshopper

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    OK, so essentially what I was doing is introducing so much cross talk that I want able to get data through it? But the shorter patch cable was short enough as to not be significant (5ft), but at 35ft it's significant?

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  11. tangent

    tangent Known around here

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    Ethernet is sent as a differential signals over twisted pairs. Meaning there's a positive and negative version of the same thing sent over each wire of a twisted pair. The twists purpose is to add capacitance to the cable. It actually be a bit more than crosstalk when you mess this up.

    It's possible that the twisted wires in your other cable don't follow the normal color scheme.
     
  12. awsum140

    awsum140 Getting the hang of it

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    Did you test the cables with a tester? If they "rang out" there could have been a wiring error depending on the tester. Some test as single connections 1 to 1, 2 to 2, ect, others test the pairing, orange, green, etc. Worst case, cut the ends off and start over again. It does take some practice, and patience, to be able to do it well and quickly.
     
  13. TonyR

    TonyR Getting comfortable

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    Nice color code chart at post #6 ==>> here.
     
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