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sensing 120vac

jrcowboyjrcowboy Posts: 1
edited 2005-02-10 13:33 in BASIC Stamp
whats the best (and most robust) hardware solution to input a 120-240VAC signal to the stamp?

joel

Comments

  • Jon WilliamsJon Williams Posts: 6,491
    edited 2005-01-27 20:50
    Use an opto-isolator. Opto-22 makes a module that will let you put 120 VAC in and get a TTL level out.

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    Jon Williams
    Applications Engineer, Parallax
    Dallas, TX· USA
  • Pinoy NYCPinoy NYC Posts: 30
    edited 2005-02-10 05:13
    Jon,

    what will be the output in voltage of the OPTo-22 if you feed a 120VAC?
    will that be around 5VDC?

    Thanks.
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2005-02-10 13:33
    OPTO-22 makes modules that are TTL compatible. I believe they have a pull-up on the output pin which would put the output at five-volts with no AC present; when the signal arrives the output line is pulled low.

    http://www.opto22.com/asset/documents/0251_G4_Digital_AC_Inputs_data_sheet.pdf

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    Jon Williams
    Applications Engineer, Parallax
    Dallas, TX· USA
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