Arduino Uno + Motor Shield + Big Stepper Motor

I got the basics on controling a stepper motor via Arduino Uno Thru the motor Shield. My problem is, I would like to use a motor that is more powerfull (6.5 A), how can that be accomplished?

any help is appreciated.


How often and how far will it be running at full speed? Will there be large breaks where it stops for awhile? How fast will it be going most of the time? Depending on your answers, there may be a shortcut.

it will be running about a couple of full turn every 10 min. In between the motor might be turning a few steps in each direction every 20 seconds or so... as far as speed goes I would like it to ge at 150 rpms or higher.

How strong, how much holding torque, does it have to have when it's not moving? There may be a way to lower the 6A current when it's stopped. In this case you could use an L298 to provide 6.5A briefly, to meet the requirements you specified. The lower current can be designed with hardware at a predefined value, and 8 digital pins total, or PWM, then you can adjust it in the code.

it does not need to have any holding torque when it is not moving... I read somewhere that I can just piggy back more chips onto the motorshield to increase the current it can handle... is this information accurate? if not, I might have to end up buying a stronger motor driver but how is that controlled thru an arduino?


There is no need. But yes, you could. L298 can handle the duty cycle you specified even at about 6A. It will not get warm rotating a few turns every 10 minutes. What voltage would your motors require to get 6A to flow?

Now I am using a 1A 8V rated motor and I am using a 9V power source to power it. I do not have a lot of experience with motors and controls but what I know is for the application I will need more torque. After talking to few people and showing them the intended application, I was told that a 4 to 6A motor will do the trick. So I started looking for that size motor and I found a few that are rated for less than 18V...

  • I wanted to give you a run down of what I have been doing that way if there is a flaw somewhere you can point it out.
  • Again, I am not the controls expert; but I was told somewhere that for the 8V rated motor to deliver more torque/speed, I can increase the voltage for the power source of the motor.

I hope you can help me solve the above issues.

Thanks a lot!