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Thread: Cat 6 termination, A or B?

  1. #11
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    apologies to infinity and mcgraw, but calling 8p8c jacks RJ-45 is as maddening to telecom guys as "ground up or down" threads are here.
    Electricians do it until it Hertz!

  2. #12
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    btw, welcome to the forum azebra. curious as to why you are using cat6... did the HO buy it? do the cameras spec it? having punched down tens of thousands of pairs of cat3, cat5e, and cat6 (some 6A), cat6 is a pita to terminate. If you're doing any amount of it, you will get carpal tunnel in short order.
    Electricians do it until it Hertz!

  3. #13
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    Quote Originally Posted by JFletcher View Post
    apologies to infinity and mcgraw, but calling 8p8c jacks RJ-45 is as maddening to telecom guys as "ground up or down" threads are here.
    YES! And the same goes for an 6p4c or 6p6c (occasionally an RJ-11, but also -12, -14, and a few others).

    (Add to that calling a PC serial port connector a "DB-9"; the second letter is the shell size, so the usual 9 pin one is a DE-9; 15 pins is a DA-15, 25 pins is DB-25, etc etc.)

  4. #14
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    Quote Originally Posted by infinity View Post
    Nope you're incorrect. I checked them personally with a pair tester and all of the cables tested good...
    Most testers won't pick up split pairs. You can wire a plug any old way and as long as the other end is wired the same the tester will say good.

    -Hal

  5. #15
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    Quote Originally Posted by JFletcher View Post
    apologies to infinity and mcgraw, but calling 8p8c jacks RJ-45 is as maddening to telecom guys as "ground up or down" threads are here.
    Ahhh! Now there's a breath of fresh air!

    Quote Originally Posted by zbang
    YES! And the same goes for an 6p4c or 6p6c (occasionally an RJ-11, but also -12, -14, and a few others).
    Lets not get carried away now. The USOC designations are still used although many designations like RJ-45 have no use today.

    RJ-11 is your standard 1 pair phone jack or plug- 6p4c or 6p6c with T&R wired to the center pins 3&4.

    RJ-14 is a 2 pair 6p4c or 6p6c jack or plug with the first pair on 3&4 as above and the second pair on 2&5. It could be used for two lines or commonly for office phones that use two pairs.

    Extra credit: Does anybody know what a RJ31x jack is?

    -Hal

  6. #16
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    Quote Originally Posted by hbiss View Post
    Extra credit: Does anybody know what a RJ31x jack is?
    Of course . I still have a Suttle Apparatus USOC guide (two shelves down from Reference Data for Radio Engineers and a few editions of American Electrician's Handbook).

    I have a lot of old books.

  7. #17
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    Quote Originally Posted by hbiss View Post
    Most testers won't pick up split pairs. You can wire a plug any old way and as long as the other end is wired the same the tester will say good.

    -Hal
    I'm not sure that I follow, you have 8 conductors (4 pairs) straight through that passed via a pair tester. The problem as I stated earlier was that the incorrect pairs had been used so the twists per inch for each pair were incorrect.
    Rob

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    All responses based on the 2014 NEC unless otherwise noted

  8. #18
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    Quote Originally Posted by hbiss View Post
    Ahhh! Now there's a breath of fresh air!


    Extra credit: Does anybody know what a RJ31x jack is?

    -Hal
    I'm recalling a jumper across terminals 2 & 3 providing a tamper loop for a security alarm panel, otherwise the same as a RJ-38.
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  9. #19
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    Quote Originally Posted by infinity View Post
    The problem as I stated earlier was that the incorrect pairs had been used so the twists per inch for each pair were incorrect.
    At least for Ethernet, I can't see how that matters; the reason the rates differ is to reduce crosstalk between pairs but otherwise they're just twisted pairs.

    I also don't see how the terminal equipment can actually tell the twist rates of the different pairs, but I'm not up on the low-level physics involved.

  10. #20
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    Quote Originally Posted by zbang View Post
    At least for Ethernet, I can't see how that matters; the reason the rates differ is to reduce crosstalk between pairs but otherwise they're just twisted pairs.

    I also don't see how the terminal equipment can actually tell the twist rates of the different pairs, but I'm not up on the low-level physics involved.
    That's what we thought too, until the cameras didn't work. When we tried one of the cable supplied with the cameras it worked. When we changed the pinning to reflect what the manufacturer specified because of the individual pair twists it worked.
    Rob

    Moderator

    All responses based on the 2014 NEC unless otherwise noted

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