Help with solar tracker

Discussion in 'The Projects Forum' started by prem25, Feb 18, 2011.

  1. prem25

    Thread Starter New Member

    Feb 14, 2011

    I hope you would be able to help!

    I am working on a solar tracker and being a mechanical student I am really struggling with the electronics behind it, unfortunately!

    All I am trying to do is run two DC motors (since it is a dual axis tracker) with 4 sensors (2 per motor).

    I am trying to simulate the circuit (for single motor/2 sensors) on with NI Multisim till no avail. Dual OP-AMP (LM1485) is required in the circuit but I am not able to find this specific component on Multisim's database and hence used MC1458CG (Motorola equivalent). For LDR's and trimpots (rheostat) I have used variable resistors (Potentiometers in Multisim). Please advise me should I am wrong!

    I am attaching a few screen shots. Please advise! Thanks.

    PCB:- pic1.jpg
    Schematic:- pic2.jpg
    E-PCB (soldering purpose):- pic3.jpg
    Bill of Material; Transistor:- pic4.jpg
    Schematic on NI Multisim Software:- pic5.jpg

    Any piece of advice would be highly appreciated!:)
  2. edgetrigger


    Dec 19, 2010
    If you want to simulate the current through the motor then add a resistor equivalent to the resistance of the motor in series to the multimeter.

    If you dont have the resistance value you may assume some 20 ohms.

    When motor changes direction the polarity of the current reverses.
  3. prem25

    Thread Starter New Member

    Feb 14, 2011
    Hi edgetrigger,

    thanks for your reply but the problem was something else and that I have resolved myself. If you see closely the connections I have made on the potentiometer are incorrect.

  4. george62

    New Member

    Oct 22, 2011
    sorry guys can anyone tell me why those specific resistances are used in this case ?