DC Motor Control using DAQ 6009

[Mani-Tech]

Hi, 

I am a Mechanical Engineering student and have relatively less knowledge with usage of NI DAQ.

I have tried running a DC Motor using the analog voltage signal generated from DAQ 6009.

I have used 0 - 5V , RSE and one sample on demand and the AO0 port in the DAQ and a numerical slider to control the voltage level.

But the motor is not running. Kindly suggest how to solve this...And if it is the form of a VI example , it will be much helpful. 

Thanks in advance.

[Nate.H]

Hi Mani-Tech,

Look at your motor power requirements. The NI USB 6009 can only source 10mA total.

For common small brushed DC motors, that doesn't even register on the Torque Speed curve

http://pdf.directindustry.com/pdf/ametek-technical-industrial-products/pittman-motors/14270-133515-_...

Even for realllly small brushed DC motors, the USB 6009 alone cannot source enough current to drive the motor:

https://downloads.maxonmotor.com/Katalog_neu/eshop/Downloads/Katalog_PDF/maxon_dc_motor/A-max-progra...

To control a brushed DC motor, you need a power source that will supply the required current at the right voltage based on your motor specifications. 

You will also need a drive circuit to vary the current in the motor windings. The complexity of this drive circuit will depend on what you want your motor to do.

Finally, you will require a controller to generate the PWM signal(s) that are inputs to the drive circuit. 

This is a good starting point for knowing what you will require:

http://ww1.microchip.com/downloads/en/appnotes/00905a.pdf

Best Regards,

Nate

[Mani-Tech]

HI Nate,

Thank you for your suggestions.

I have designed a temperature control system with the DAQ. When the temperature goes above  a certain level the motor should switch ON.

I have attached the connection diagram with this post. I measured the voltage across the DAQ output. It shows only 0.8 V.

But the motor runs continuously without any control from the DAQ. And the motor ran when I connected it directly to the power supply at about 2V itself.

So kindly guide me in this issue.

[Mani-Tech]

Hi Nate,

A few more doubts. The transistor serves as amplifier or a switching device in that appplication?

Is the drive circuit in the attachment is actually correct? My lab assistant says that it is correct. But I wonder why the circut is not working.!!

[kabi]

Even i want to control a DC motor using LabVIEW.

Hi, I am trying to control the speed of a 36V 2.5Amp 3000 rpm max speed DC Motor using LabVIEW.

I need someone to guide me what are the hardware required to do this.

1) Which DAQ is most suited for controlling the DC motor ?

2) Any other hardware required such as a controller, etc ?

3) Any example programs for DC motor speed control ?

4) Any circuit diagrams explaining the connections to be made.

I will be grateful if someone helps me with the above said things