Close



Page 3 of 5 FirstFirst 12345 LastLast
Results 21 to 30 of 43
  1. #21
    Technologist GOC's Avatar
    Join Date
    Nov 2014
    Location
    Huron County, MI
    Posts
    194
    Add GOC on Google+ Add GOC on Thingiverse
    Quote Originally Posted by BLKKROW View Post
    How would you measure the voltage?
    - Measuring the voltage will vary depending on what type of board you have and how the driver input power is sent. The place you need to measure the voltage is at the "Driver Power" source; see image below for an example.


  2. #22
    Engineer-in-Training
    Join Date
    Jul 2014
    Posts
    305
    Quote Originally Posted by GOC View Post
    - Measuring the voltage will vary depending on what type of board you have and how the driver input power is sent. The place you need to measure the voltage is at the "Driver Power" source; see image below for an example.
    Thank you for the information! Do I have to measure the voltage while the motor is running? Or can I just have the machine on?

  3. #23
    Technologist GOC's Avatar
    Join Date
    Nov 2014
    Location
    Huron County, MI
    Posts
    194
    Add GOC on Google+ Add GOC on Thingiverse
    Quote Originally Posted by BLKKROW View Post
    Thank you for the information! Do I have to measure the voltage while the motor is running? Or can I just have the machine on?
    Just needs to be on.

  4. #24
    Engineer-in-Training
    Join Date
    Jul 2014
    Posts
    305
    Quote Originally Posted by GOC View Post
    Just needs to be on.
    I finally had time to open up my machine and found the following:



    I presume to measure the voltage I use the GND and VMOT, is this what you would do?

    Edit: When I measure the voltage through the above mentioned terminals, I am reading 24 volts. This doesn't sound right.
    Last edited by BLKKROW; 01-18-2015 at 09:53 PM.

  5. #25
    Technologist GOC's Avatar
    Join Date
    Nov 2014
    Location
    Huron County, MI
    Posts
    194
    Add GOC on Google+ Add GOC on Thingiverse
    Quote Originally Posted by BLKKROW View Post
    ...
    I use the GND and VMOT, is this what you would do?
    ...
    - Yes, that is correct.

    Quote Originally Posted by BLKKROW View Post
    ...
    I am reading 24 volts.
    ...
    - Yes, this is also correct. Seems like your running a 24v setup, which is very nice because they tend to draw less amps. That will however make a lower voltage motor get real toasty for sure. You'll need a motor in like THIS (I don't know this seller; just using as reference).

    Edit: Make sure to use the GND that's next to the VMOT when measuring, not the one at the top.
    Last edited by GOC; 01-18-2015 at 10:08 PM. Reason: Additional Info Added

  6. #26
    Engineer-in-Training
    Join Date
    Jul 2014
    Posts
    305
    Quote Originally Posted by GOC View Post
    - Yes, that is correct.



    - Yes, this is also correct. Seems like your running a 24v setup, which is very nice because they tend to draw less amps. That will however make a lower voltage motor get real toasty for sure. You'll need a motor in like THIS (I don't know this seller; just using as reference).

    Edit: Make sure to use the GND that's next to the VMOT when measuring, not the one at the top.
    Would that be Nema 17 or 16?

    I am just trying to find one from a reliable retailer.

    Edit: Sorry I see it listed as Nema 17, I just cannot find a 24v stepper motor anywhere but eBay.com
    Last edited by BLKKROW; 01-18-2015 at 10:21 PM.

  7. #27
    Technologist GOC's Avatar
    Join Date
    Nov 2014
    Location
    Huron County, MI
    Posts
    194
    Add GOC on Google+ Add GOC on Thingiverse
    Quote Originally Posted by BLKKROW View Post
    Would that be Nema 17 or 16?...
    - I'm not certain of that, I think Geoff might have more experience for identifying the motor type. I'm more of a circuit board expert.

    Quote Originally Posted by Geoff View Post
    ...
    Measure it, if it is 4cmx4cm, just buy a standard NEMA17...

  8. #28
    Senior Engineer
    Join Date
    Jun 2014
    Location
    Burnley, UK
    Posts
    1,662
    Working voltage on stepper motors in the days of modern electronics is meaningless. The driver circuitry is a current limiting device so no matter what voltage the stepper is rated at it is the current that is controlled.

    If your driver circuitry cannot achieve the maximum rated current of the motor then the motor will not produce maximum torque.

  9. #29
    Technologist GOC's Avatar
    Join Date
    Nov 2014
    Location
    Huron County, MI
    Posts
    194
    Add GOC on Google+ Add GOC on Thingiverse
    Quote Originally Posted by Mjolinor View Post
    Working voltage on stepper motors in the days of modern electronics is meaningless...
    - I don't know about that, from my knowledge of motors the winding is specific to the voltage required for optimal operation (hence the motor rating). I gained my some of my stepper knowledge from THIS PDF & THIS PDF. High voltage motor winding's tend to give more running and holding torque.

  10. #30
    Senior Engineer
    Join Date
    Jun 2014
    Location
    Burnley, UK
    Posts
    1,662
    Quote Originally Posted by GOC View Post
    - I don't know about that, from my knowledge of motors the winding is specific to the voltage required for optimal operation (hence the motor rating). I gained my some of my stepper knowledge from THIS PDF & THIS PDF. High voltage motor winding's tend to give more running and holding torque.
    Which is what I said worded in a different way.

    If you have 2 stepper motors, one being 12 volt and one being 24 volt but both rated at 2 amps then the power output, at maximum volt and current, of the 24 volt one will be twice the power output of the 12 volt one (assuming the same efficiency).

    If you run them from 12 volt then the power output from both motors will be the same because it is the current that is regulated, not the voltage.

    In reality the 24 volt one will produce slightly less power than the 12 volt one when running from 12 volt because the magnetising power needed on the 24 volt one will be higher than the 12 volt one but you will not notice a difference in real usage.

    In the environment of 3d printers you are unlikely to come anywhere near needing the maximum of any stepper motor no matter what voltage or current it is rated for.

    The stepper driver limits the current, it doesn't care what voltage you apply as long as you do not exceed the maximum of the driver circuitry which is around 35 volts for the chip that is most commonly used.

    If you set the current to some value less than the V/R value of the system then all that will happen is that the stepper driver will drop the voltage applied to the stepper motor because the stepper motor must obey Ohms law whereas the stepper driver does not obey Ohms law. This is assuming that we are not in the realms of the dynamic impedance of the motor affecting the current flow which we will almost certainly never be with the speeds used in these types of machine.
    Last edited by Mjolinor; 01-19-2015 at 06:31 AM.

Page 3 of 5 FirstFirst 12345 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •