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Cat 5 cable connections

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Wp100, Dec 1, 2017.

  1. Wp100

    Wp100 Active Member

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    Hi,

    Am using some cat5 cable to send rs232 data over about 15 mtrs.

    Is the right way to connect the wires to use a twisted pair for both the send and receive lines, or to use a pair for each signal line with ground ?

    thanks.
     
  2. JimB

    JimB Super Moderator Most Helpful Member

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    It would be better to use one pair as TxD and Gnd, and a second pair as RxD and Gnd.

    This way, cross talk between TxD and RxD will be minimised.

    In practice, it may be difficult to see the difference, but why invite problems when you don't have to.

    JimB
     
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  3. kubeek

    kubeek Well-Known Member

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    And the best option would be to use RS422 transceivers to fully utilize the capabilities of twisted pair cable.
     
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  4. dave

    Dave New Member

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  5. Wp100

    Wp100 Active Member

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    Had just received a pair of these little max3232 modules, but they do not seem to work on the bench.

    Can see the 9600 baud signal going in, and the pcb traces to the chip and i/o pins measure ok , but the output pin just shows a 4v high on the scope... ?

    Long time since I played around with the max chips, thought these little modules would be a simple lo cost option, will have to search the junk box and see if I have any dip max chips still around.


    000511.jpg
     
  6. dr pepper

    dr pepper Well-Known Member Most Helpful Member

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    If its Stp connect the drain wire to ground.
    There are some versions of the dip package that work with larger electrolytics, and some with 100n caps.
     

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