Use DC PWM Speed Controller as Potentiometer?

Hi There,

I have this speed controller here: Speed Controller

It only has power + - and motor + -
Normally a potentiometer has 3 pins? So, can I use it as a simple pot and if yes how to wire it to the arduino?

Thanks

ardustar:
Normally a potentiometer has 3 pins? So, can I use it as a simple pot and if yes how to wire it to the arduino?

I would not think that is possible.

You need to provide more information. Are you trying to replace a potentiometer in something? If so, what?

...R

I just want to control the speed of a stepper motor and thought this speed controller could do this. But it seems it is not the right tool for the job....

ardustar:
I just want to control the speed of a stepper motor and thought this speed controller could do this. But it seems it is not the right tool for the job....

That is not enough information.

What is controlling the stepper motor?

Why not just use a potentiometer?

And those two questions barely scratch the surface of what you are not telling us. Please describe the complete project and all its components and how they connect together.

...R

ardustar:
I just want to control the speed of a stepper motor...

Can't.
It's a brushed DC motor driver.
Leo..

Robin2:
Why not just use a potentiometer?

…R

Ok, I think here is my problem - I thought this thing is a pot when I bought it. seems like it is not. :slight_smile:

I am using an Uno, cnc shield mwith a A4988 driver and a 17 hS13 motor.

To adjust the speed of a stepper motor, adjust the time interval between step pulses sent to the driver.

ardustar:
I am using an Uno, cnc shield mwith a A4988 driver and a 17 hS13 motor.

Then post your program and tell us what extra feature you want to add to it.

Also post a link to the datasheet for the stepper motor.

...R

PS ... I have just seen that you have another Thread about the same problem in which you have been getting the same advice. Don't double Post.

If you click Report to Moderator you can ask to have the two Threads merged

Actually that is not the same problem.
Over there I could not get the motor to turn at all, without any speed control.

I don’t want to change the speed of the motor using the code, but want to be able to change it while it is in operation using a potentiometer. For this I bought the part mentioned in post one.
but it seems this is not usable as a pot - I just wanted to get info here if I am missing something and this thing is able to be wired to the shield like a pot (3 wires).

So all good, I’ll get myself a “real” pot and give it a try.

ardustar:
I don’t want to change the speed of the motor using the code, but want to be able to change it while it is in operation using a potentiometer.

That is completely illogical.

The only thing that can change the speed of the stepper motor is the program code. And the program needs to read the position of the potentiometer and then figure out the interval between steps to create the speed you wish to operate at.

…R

Robin2:
That is completely illogical.

The only thing that can change the speed of the stepper motor is the program code. And the program needs to read the position of the potentiometer and then figure out the interval between steps to create the speed you wish to operate at.

...R

Hi R,

I know. I was referring to the post of outsider, which I understood in the way " why use a pot, use the code".
But to change the speed of the motor WITHOUT being connected to the Uno I need a poti - which I thought I had bought, but obviously had not. :slight_smile:

But a few 3 wire potentiometers just arrived, and I think I will find good use for that PWM controller somewhere.

So thanks to all for trying to help me.

Hi there,

I need help again on this topic.

I just realized that the cnc shield on top of my arduino is blocking the analog-in pin for my potentiometer.
Is there a way to connect somewhere on the shield and get the arduino to read that signal?

ardustar:
I just realized that the cnc shield on top of my arduino is blocking the analog-in pin for my potentiometer.
Is there a way to connect somewhere on the shield and get the arduino to read that signal?

Have you posted a link to the datasheet for the CNC shield?

...R

A0-A3 probably go to the Abort/Hold/Resume/E-stop pins (of the white row). The black row is probably ground.
If you don’t use those pins, then you can use one of them for your pot.
Leo…

@Robin2

No, thnks for reminding me.
I don't know the real manufacturer of the shield, but I found this here:
CNC SHIELD V3.0

Hopefully the information there helps?

It looks like you could use analog pins 3, 4 and 5. It says 4 and 5 are reserved so you may need to explore exactly what that means.

...R

But how do I connect to them with the shield on top??

ardustar:
But how do I connect to them with the shield on top??

As far as I can see there are sockets on the shield that connect to those pins - study the schematic.

...R