Communicating with DC motors.

Forum 2005-2010 (read only) Hardware Troubleshooting
1

Hi All,

I'm looking for some help running a dc motor. I'm looking to buy a 24v DC motor and a power supply to run it.

I need to understand the process of linking the Arduino board to the motor.

So starting with the Arduino, I beleieve i need some form of Driver for the motor, but how does the driver connect to the motor ? does it connect direct or do i need some form of relay inbetween the driver and the motor or do i connect the driver board to the power supply ???

The power supply and motor i'm looking at are shown below.

Thanks,
Rich.

2

Have a look at my motors tutorial:-
http://www.thebox.myzen.co.uk/Workshop/Motors_1.html

3

Hi Grumpy_Mike,

Thanks for the tutorial, I think that went a bit over my head trying to follow it all.

I think for myself, to make it easier for me to understand, i'm not looking for the priciples of making a motor driver, but more a case of people recommending a driver board for the Arduino and and explaining how this is connected to the motor/Power Supply

Rich.

4

OK there are lots of motor shields arround. This is just one I picked at random.

5

Mike,

Thanks for the link. I know i've got to use a driver, the bit i need to understand is how do i wire the Arduino to a driver board and then to the motor / power supply ?

I've made a basic drawing, i just want to understand if i have the basic concept right.

![](http://astrosky.co.uk/images/general/Arduino Setup.jpg-for-web-LARGE.jpg)

6

Yes but you have to connect the ground on the arduino to the ground on your external power supply as well.

7

Thanks Mike,

Appreciate that. So why do you have to ground to External Supply ?

Regards,
Rich.

8

Without a common ground, either things wont happen, OR worse... BAD things happen. When dealing with multiple supplies, you want to always make sure the grounds are all connected together.

9

Mikes even got a tutorial about that!:smiley:

http://www.thebox.myzen.co.uk/Tutorial/Power_Supplies.html

10

Keep in mind when utilizing commercially available motor drives that the ground connection between motor supply and logic supply may already be made on the driver board, or it might not be required in the case of drivers using optical isolation design.

Always check out the driver instructions or data sheet for these kinds of details.

Lefty