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pwm using USB 6009

Dear Sir,

              I am working on dc motor control. for that purpose im using USB 6009. I would like to control the DC motor using half bridge so that pwm signals will generate. so that im using A0 as analog output. but im unable to do so. please help me on this issue.

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Message 1 of 18
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First, I would think that PWM would be a lot easier to generate with a Digital Output channel.

 

Second, what code do you have so far that we can look at?

 

Mike...


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Message 2 of 18
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Nevermind, double post...

 

Mike...


Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion

"... after all, He's not a tame lion..."

For help with grief and grieving.
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OK so you have a DC motor and a 6009.  Lets "Go to school"

 

The speed of the motor will be proportional to the average power supplied so for any RMS voltage applied we can find the current consumed given the motors resistance proving what we just stated.

 

PWM modulation is often used to vary the RMS voltage applied from 0-100% of the peak voltage (That's what Pulse Width Modulation means)  AO could do the exact same function

 

The problem being that unless that is a very very small motor with little mass moving against no mechanical friction you will need more power than a 6009 can source.


"Should be" isn't "Is" -Jay
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In addition to the earlier posts this is a reminder that the USB-6009 AO (and Di/O) is software timed. The resulting jitter may make the performance erratic and jerky.

 

Lynn

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Message 5 of 18
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Hello all,

 

I am also trying to run DC motor with 6009 and SN754410 h bridge.

I manage to run this on Arduino, so the circuit is ok.

Now trying to run with 6009.

I need to adjust speed, with changing the duty cycle of PWM. Problem is because with simulte signal I can't run motor.

Please advise how to continue...

 

Check VI in att.

 

Thank you.

Milan. 

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Message 6 of 18
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Hi Milan,

 

as has been written by Lynn 5 years ago that USB6009 only supports "software-timed" AO/DO signals. It will not output your simulated waveform in a determinable manner!

 

The USB6009 is the wrong DAQ device when you want to output reliable PWM signals (for frequencies >1Hz)…

 

Please advise how to continue...

Check your requirements. Then choose/buy DAQ hardware fulfilling your requirements…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
Message 7 of 18
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I am trying to control a DC motor using USB 6009 generated PWM and Digital Outputs that feeds into a Sparkfun motor driver: TB6612FNG. With all the wiring done and Digital Output set-up using NI Max and a VI for DO based PWM, the motor runs only on top speed [in CW and CCW direction based on the particular DO high/low], but I am not able to control the speed itself [it is as if the motor driver is not recognizing the PWM output from the DAQ via LabVIEW]. I see that USB 6009 is not the best DAQ HW for PWM generation, but anybody know what could be behind this lack of any speed control at all? Thank you.

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I used arduino for PWM and it did a good job. 

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Thanks. The arduino should work well [the sparkfun guide is based on that]. The Arduino requires the speed to be coded in, but then if I want to control the speed via Labview input, do you have any recommendations?  

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