. .
  1. #1
    One of these stepper motors that I have is not working properly:

    http://www.slidesandballscrews.com/s...ml?cPath=45_81

    The max rpm has suddenly decreased greatly - won't go above 620 rpm with no load. It just misses steps, or just stalls whilst accelerating.

    I've tried it on to other identical, PM752, drivers running on 70v and get the same symptoms - so it's not the driver that's the problem.

    My other 3 of these steppers are all fine...

    Any ideas what could be wrong / where to go from here?

  2. #2
    Ok well that was weird ... it's suddenly started working just fine!
    Still, I'd like to know what might have caused it so it can't happen whilst the machine is running.

  3. #3
    Is it possible you overheated the rotor and it eventually cooled down?

  4. The Following User Says Thank You to Robin Hewitt For This Useful Post:


  5. #4
    No, the motor had only been on a few seconds, and off for about a month. Not warm at all. It happened just after I'd installed 4th stepper driver and cleaned out all the dust from the computer.

  6. The Following User Says Thank You to Jonathan For This Useful Post:


  7. #5
    Maybe dodgy connections since you rewired it several times if it is a dodgy connection I would think it inside the stepper motor.

    You can split steppers to check have a look on you tube.

    I wouldn't trust a motor that had done that to me unless I traced the reason it happened because it'll cost a lot more than a new motor would if it starts skipping steps on a work piece.
    http://www.mycncuk.com/threads/10880...60cm-work-area My first CNC build WIP 120cm*80cm

    If you didn't buy it from China the company you bought it from did ;)

  8. #6
    You do realise this post is 7 years old. Also it is not a good idea to open a stepper motor.
    ..Clive
    The more you know, The better you know, How little you know

  9. The Following User Says Thank You to Clive S For This Useful Post:


  10. #7
    No I didn't lol, I would think as long as you de-energized the coil you have nothing to lose going inside. I'm going to rip one open to see what's inside but it's a scrap one.
    http://www.mycncuk.com/threads/10880...60cm-work-area My first CNC build WIP 120cm*80cm

    If you didn't buy it from China the company you bought it from did ;)

  11. #8
    I have no recollection of this incident, though I can say that 7 years later all the 3Nm motors I have from Zapp and CNC4You are still working well.

    I agree with Clive on not dismantling without good reason - apparently this can result in demagnetisation.
    Last edited by Jonathan; 10-05-2017 at 08:59 PM.
    Old router build log here. New router build log here. Lathe build log here.
    Electric motorbike project here.

  12. The Following User Says Thank You to Jonathan For This Useful Post:


  13. If you remove the rotor from a stepper motor it will demagnetise very quickly and then when you re assemble, it will not have the rated torque that it had before you stripped it down.

  14. The Following User Says Thank You to Gary For This Useful Post:


Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Congratulations to Gary @ Zapp
    By JAZZCNC in forum General Discussion
    Replies: 7
    Last Post: 21-09-2013, 07:44 PM
  2. Zapp 3-Axis kit - putting it all together
    By birchy in forum Motor Drivers & Controllers
    Replies: 5
    Last Post: 18-02-2013, 12:05 PM
  3. Zapp Automation CNC Driver Kit 4 Axis
    By whensparksfly in forum Motor Drivers & Controllers
    Replies: 7
    Last Post: 01-03-2012, 01:54 PM
  4. ZAPP SY60 wiring help
    By Smiler in forum Stepper & Servo Motors
    Replies: 7
    Last Post: 07-06-2010, 08:28 PM
  5. Air compressor - faulty, how do I get the motor out?!
    By HankMcSpank in forum General Discussion
    Replies: 5
    Last Post: 26-10-2009, 11:33 AM

Bookmarks

Posting Permissions

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