Small controller with big stepper motor

Discussion in 'The Projects Forum' started by victorprmt, May 11, 2010.

  1. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    Hi
    I have a 3-axis 12 Volt, 800mA, stepper motor controller and I install 2
    (X and Y) with 12VDC, 30 ohm, BIPOLAR motor and I need to install the third one (Z) with 12VDC, 2 amp. BIPOLAR motor in the same controller my question is: how I need to do
    Vic.
     
  2. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    What is the manufacturer and model of your controller and motors?

    If you have datasheets or links to the parts, this would help us help you.
     
  3. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
  4. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
  5. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    You have these already? What do you need help with?
    If you already have 2 motors hooked up, why are you having a problem with the third motor?

    What is causing your problem?
     
  6. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    Your stepper motors have 6 wires each. The gadgetMaster has to be set up to option B Option B is selected with a jumper on the gadgetMaster board. This allows you to have 12 outputs instead of the normal 8.

    You put the 4 driving wires for each motor on pins 1 through 12. The remaining 2 ground wires on each motor goes to the GND pins.
     
  7. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    I need the Z-axis with more torque, stronger for my special application
     
  8. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    Page 10 of the users manual shows you how to wire the motors. It shows which color wires go where.

    Here is the link:
    http://www.lightmachinery.com/GM Users Guide rev 6.1.pdf

    Remember, you need to change the jumper on the gadgetMaster board to 'B' in order to use all 12 outputs.
     
  9. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    To get more torque, use 'TWO-PHASE' stepping mode for the Z-Axis stepper. This will double the current, and increase the torque.
     
  10. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    The problem is that the controller is a 800mA for drive small motors steppers and I need one of the 3 to be bigger 2 amp
     
  11. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    Ahh. You need a more capable stepper driver.

    You only need to get one. The one your using is fine for X and Y correct?

    So you only need a single driver for the Z.

    Where are you located? Do you want to buy of build a stepper controller?
     
  12. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
  13. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    Tanks Retched but I am lost how I connect this
     
  14. retched

    AAC Fanatic!

    Dec 5, 2009
    5,201
    312
    I do not exactly know. You will have to read the GadgetMaster manual and the stepper driver manual to see how they connect together.

    You should be able to use the outputs on the gadgetMaster to tell the 2A stepper driver what to pulse. The Z-axis stepper motor will connect to the new 2a driver.

    But, you will have to read both manuals to see what goes where.
     
  15. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    Tanks I will do that
    We are in touch
     
  16. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    Well, why don't you ask the company how to increase the drive in one of the channels?
     
  17. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    They don’t know and they don’t want take the risk but I know that it is possible the problem is that I don’t know
     
  18. John P

    AAC Fanatic!

    Oct 14, 2008
    1,634
    224
    I can imagine doing this by making the existing driver control 4 power transistors; 2 amps each isn't much of a challenge. What is the power source for this 12V system? Can it meet the total current requirement? That seems to be 7.2 amps, if you draw .8 amp for 2 phases in each of 2 motors, plus 2 amps in 2 phases of one motor (1.6 + 1.6 + 4). But obviously you shouldn't have a power supply that's rated just barely high enough to give what you need.
     
  19. victorprmt

    Thread Starter New Member

    May 11, 2010
    11
    0
    Hi John

    Please see this attachment, what do you think?
     
  20. John P

    AAC Fanatic!

    Oct 14, 2008
    1,634
    224
    In that circuit diagram you seem to have resistors instead of diodes. The pictorial view has diodes, but they should connect to 12V rather than Gnd. But are those transistors 2N3904? The lettering is kind of small--but they won't work! In fact there may be some fireworks. That transistor isn't rated for 2 amps or even 800 milliamps. I don't know every transistor that exists, but I'd expect to use something in a TO-220 case; maybe the TIP31 or something similar.

    Also, you need to be sure that the driver board sources current rather than sinking it, if you want to drive NPN transistors. If it sinks current, you'd have to turn the circuit upside down and use PNP power transistors--and then the diodes should indeed connect to Gnd! Sorry this is all a little complicated.
     
Loading...