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DIY RS-232 to RJ-45 Connectors to Cat5E Cables for Serial Connections

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    DIY RS-232 to RJ-45 Connectors to Cat5E Cables for Serial Connections

    I have two Digi Edgeports and all of the serial (16) connections use the RJ-45 to RS-232 connectors and conventionally wired RJ-45 cables. I have used this for Homeseer serial connectivity for years now. The RS-232 runs go from one corner in the basement to the Kitchen, Garage, second floor and attic with runs up to maybe 100 feet or so.

    Just take your time making up the RJ-45 to RS-232 connectors.

    Material list

    1 - Cat5E cable
    2 - RJ-45 ends
    3 - unpinned RS-232 female and male to RJ-45 connectors. (shop around for a good price under $3 or so each).
    4 - RJ-45 compression tool
    5 - RJ-45 tester (el cheapo $5 will work to test continuity).

    I attached a picture which I still use today for making the connectors. I do utilize all 8 of the Cat5E wires even though you mostly can get by with just 3 wires. Aside from the colors of the wires there are little numbers adjacent to the pins/holes which will help you wire it up. If you make a mistake there is also a tool you can purchase to remove the pin. I have found it easier to just cut and solder messed up connections. My only issue is with the red and brown wires; under a good light though its easy to tell me apart (at least for me it is). My last serial endeavor was an auto RS-232 serial switcher such that I could control the Russound CAS44 with either Homeseer or the HAI OPII panel; works fine. (not a DIY connector).

    If you have an old serial modem, Temp05/08 or RFID device you can test out the connectivity of the RS-232 port before connecting it to Homeseer. You can also make up a null modem cable to test if you want.
    Attached Files
    Last edited by Pete; February 14, 2012, 03:21 PM.
    - Pete

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    I use these all of the time. Thanks for a nice diagram, I will file for reference.


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