Induction circuit

Discussion in 'The Projects Forum' started by jayjay23, Mar 2, 2012.

  1. jayjay23

    Thread Starter New Member

    Sep 30, 2011
    can someone please help me design a simple induction circuit.
    In my first circuit i used a LDR as a sensor to track a white/black line. but for my second circuit i want to replace the LDR with an inductor and be able to notice the difference when i put an inductor (coil with steal rod in the middle) close to it. i believe an inductor run on ac supply. please help me and with explanations too.

    thanks :)
  2. Experimentonomen


    Feb 16, 2011
    Not as easy as it sounds, you need a circuit that detects the slight changes in inductance and reluctance as a metallic object moves in front of the coil.
    jayjay23 likes this.
  3. JDT

    Well-Known Member

    Feb 12, 2009
    If you just want to detect the presence of a steel object - not any metal - then a Hall Effect sensor might be easier. As the iron or steel object gets closer, the magnetic field gets concentrated and the analog output changes.

    See attached drawing. You will have to experiment.

    A possible sensor:-

    You will need a slightly more complicated circuit with a comparator to detect possibly slight changes in voltage.
    jayjay23 likes this.