Object Sensor Phototransistor with a PLC Question

Discussion in 'The Projects Forum' started by lindhaw, Dec 23, 2012.

  1. lindhaw

    Thread Starter New Member

    Dec 22, 2012
    Im working on a project right now and I have a PLC and a OPB755TZ object sensor (phototransistor). Im just messing around to see if I can make a low resolution encoder from it. I have a wheel with a piece of reflective tape attached to a small motor that I would like to test this on. Before I get startedr I was wondering if I need to add a pull up resistor?
  2. Dodgydave

    AAC Fanatic!

    Jun 22, 2012