Controlling a 12v 80 watt dc motor with an Arduino

[Raymond3231976]

So I would need a better speed controller that can handle a higher amp

 

[Raymond3231976]

 

[Raymond3231976]

So do ya'll think this speed controller will do the job? And is the way it's wired together will that work or am i missing some wires anywere ?

 

[Reloadron]

So I would need a better speed controller that can handle a higher amp

No, all you need is the suggested motor driver. Why are you opposed to letting the Arduino do the motor speed control? Currently you are only using the Arduino to monitor battery voltage and make a decision to run or not run a motor based on that voltage. Why not use the Arduino to also control the motor speed? Your motor controller is designed for a PWM (speed) control input. The motor controller should also handle the motor current so why not take advantage of that?

Ron

 

[Raymond3231976]

Because I want a physical speed controller i just want the Arduino to only start and stop the voltage to the motor

 

[Pommie]

A potentiometer connected to an analogue input pin of the Arduino will be a physical speed controller.

Mike.

 

[Raymond3231976]

ok that would work also could you modify the photo i put up and show me how that would be wired up

 

[Reloadron]

A potentiometer connected to an analogue input pin of the Arduino will be a physical speed controller.

Mike.

This! You just connect the wiper of a pot to an analog in pin of your Arduino and you have your physical speed controller. Unfortunately I no longer have any of that pictorial software on this computer. I normally just do schematics. Let me see what I can find.

Ron

 

[Raymond3231976]

I use ms paint to make the picture

 

[Reloadron]

I use ms paint to make the picture

I gathered as much but the issue right now is you do not need an added speed controller since your Arduino can control motor speed with a single external pot and also monitor battery voltage to allow the motor to be run or not run based on the battery voltage. The same decision to have a motor run or not run could be made with a simple Window Comparator circuit and a single MOSFET used as a switch. Why even use a micro-controller like an Arduino? The merit to using a uC is what I mentioned earlier as to Hysteresis which I can also do with a comparator circuit. The Arduino (uC) also offers a PWM covering the motor speed which you seem to want.

Ron

 

[Raymond3231976]

Ok if I use a potentiometer connected to an Arduino can you show me how that would hook up together like I did with the picture

 

[Raymond3231976]

or do you mean all 3 pins on the potentiometer would go into the analogue input pins on the Arduino what ohm potentiometer would be best for something like this

 

[Raymond3231976]

would this work

 

[Pommie]

The potentiometer is wired between 0V (Gnd - left pin) and 5V (right pin) and the wiper (center) goes to an analogue pin. This means that at one end (anti clockwise) the wiper is at 0V and at the other end it's 5V.

Mike.

 

[Reloadron]

I will look at it closer tomorrow but at a glance you want it as Pommie mentions above:

The potentiometer is wired between 0V (Gnd - left pin) and 5V (right pin) and the wiper (center) goes to an analogue pin. This means that at one end (anti clockwise) the wiper is at 0V and at the other end it's 5V.

Mike.

We will take the analog input to your Arduino from the pot and convert the 0 to 5 volts in to a PWM out. We will run the battery voltage into another analog in channel after we divide by 3 as I mentioned earlier and let the Arduino monitor that More on all of that later.

Ron

 

[Raymond3231976]

Ok thank you both for all your help

 

[Raymond3231976]

 

[Raymond3231976]

How does this look so far

 

[Reloadron]

That looks about right. I will give you a suggestion on dividing the battery voltage down maybe tomorrow. The battery voltage will be run into another analog in so the Arduino can decide when the motor can or can not run. We will use a digital out pin to the motor controller.

Ron

 

[Raymond3231976]

Ok thanks for all the help