Need Help! Servo brake problem


Results 1 to 17 of 17

Thread: Servo brake problem

  1. #1
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default Servo brake problem

    Hi guys, I have a VMC 15XT (recently bought, bearly tested it) and I have this type of problem: I power up the machine, I go in the jog mode, where I can jog z and y axes, but x axis won't jog. On the control unit I have some kind of "2 seconds warning" - my control unit is on german, and on the read outs i have "25" on the x axis, 0 on the y, and -1 on the z axis (these are not positions, i guess those are some balancing values). Those values are about 20, 25 right after the power up, untill I hear some relays click, and at the same moment those values drop (except x value). I guess x motor brake won't release.

    Am I right? What should I do?

    Thanks in advance,

    Dragan

    Similar Threads:


  2. #2
    Member FadalCNC_Com's Avatar
    Join Date
    Aug 2018
    Posts
    21
    Downloads
    0
    Uploads
    0

    Default Re: Servo brake problem

    Ginner,

    You don't have motor brakes on the motors. If you are getting 20 or 25 on the balance screen, try adjusting it out with the BAL pot. If you cannot, then exchange the amplifiers X for Y and see if the problem follows. If so, replace the amp. If not, try exchanging the axis controller cards, X for Y and see what you get. If still having a problem, the motor would be next on the pecking order but not likely. Let me know if you need help swapping the controller cards properly and I can send you some instructions.

    Let me know if I can help further.

    FadalCNC Tech Support



  3. #3
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default Re: Servo brake problem

    Thx a lot, man! I will try this out first thing tommorow. I lack expirience with this machine, glad you replied and gave me good advices.

    Best regards.



  4. #4
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default

    Hey there, tried rotating the BAL pot - no result. Noticed LED on the x amp is not working (no light). What do I do next? Can I exchange A axis amp and x axis amp?

    Attached Thumbnails Attached Thumbnails Servo brake problem-20181113_160739-jpg  
    Last edited by ginner; 11-13-2018 at 12:23 PM.


  5. #5
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default Re: Servo brake problem

    Here is one more pic (read out, 28), sorry for the bad quality...

    I guess there it makes no sense turning the BAL pot when amp is down...

    Could it be any fuse, or something...

    Anyway, if you can send me any instructions how to change places of amps, or whatever should I do.

    I do not get any error message on the control.

    I am more than thankful for your help.



  6. #6

    Default Re: Servo brake problem

    Is this fixed yet?

    I agree that switching amps could isolate and help find the problem.

    You can switch the x and y motors the same way to see if the problem follows the part.

    It might be a long shot but see if the ball screw will move the table.

    With power off remove the x axis cover.
    The ball screw should be easy to turn by hand.

    If it moves freely then power up but don't release the E stop. When moving the ball screw you should see the x moving on the readout.

    There is a fuse on the amp board. Make sure you use the correct type. All letters and numbers must match.



    I sometimes get the same error if I manually turn (mpg) the 4 th axis too fast.
    It may take up to 15 minutes before I can get the machine running again.



  7. #7
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default

    Quote Originally Posted by Beltdrive View Post
    Is this fixed yet?

    I agree that switching amps could isolate and help find the problem.

    You can switch the x and y motors the same way to see if the problem follows the part.

    It might be a long shot but see if the ball screw will move the table.

    With power off remove the x axis cover.
    The ball screw should be easy to turn by hand.

    If it moves freely then power up but don't release the E stop. When moving the ball screw you should see the x moving on the readout.

    There is a fuse on the amp board. Make sure you use the correct type. All letters and numbers must match.



    I sometimes get the same error if I manually turn (mpg) the 4 th axis too fast.
    It may take up to 15 minutes before I can get the machine running again.

    Thanks a million for writing, man! No, haven't fixed it yet. Is it easy to switch amps? What do I need to pay attention to? Can my A axis amp be good for x axis? They seem pretty much the same to me. Do I need to adjust gain, bal, etc?

    Planning on doing it tommorow.

    Thanks a lot man, means a lot to me.



  8. #8

    Default Re: Servo brake problem

    We would normally switch x with y.

    Do you know if the machine has AC or DC drives?

    The ballance should be close enough to start the machine but will need to be fine tuned for accuracy.



  9. #9

    Default Re: Servo brake problem

    I just looked in my 6030 and the A axis amp looks physically different but are wired the same.

    I take it that you are wanting to use the A axis amp so you can run the machine without using the a drive.



  10. #10
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default

    Quote Originally Posted by Beltdrive View Post
    We would normally switch x with y.

    Do you know if the machine has AC or DC drives?

    The ballance should be close enough to start the machine but will need to be fine tuned for accuracy.

    I think I have Glentek dc servos. I don't really plan on using the A axis, so if I have defective x axis amp I will replace it with A axis amp untill I finish the job and get the old one repaired or buy a new one.

    Does it sound like a plan?

    What do you think, can it be done?

    Thanks very much, man, I dont have much expirience...



  11. #11
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default

    Quote Originally Posted by Beltdrive View Post
    I just looked in my 6030 and the A axis amp looks physically different but are wired the same.

    I take it that you are wanting to use the A axis amp so you can run the machine without using the a drive.

    That's right.

    I don't plan on using (for now) A axis. It looks the same to me, to. Do I have any special procedure for replacing the amps or is it just "swap, connect and run the program".

    Thanks a lot.



  12. #12

    Default Re: Servo brake problem

    I can't say for certain if the amps are the same between the X and A, the motors are different though.
    Under the cap on the servo motors is an encoder/resolver which are the same on DC drives.

    Normally we would check fuses and swap amps first.

    Then the encoder would be the suspect.
    And the motor last. (Most expensive and hardest to do.)

    The axis card could be at fault although I've never had to change one.

    I had a bad axis cable once that acted in the manner you described.
    It ultimately fried the motor before the problem was found.


    a mega ohm meter can help diagnose bad cables and motors.

    I've been running fadals for 20+ years now.
    In the last 10 I have been doing more and more maintence. Change motors, amps, encoders, spindles ect.
    There are 3 fadals in the shop, all have 4th axis, only 1 has DC drives.



  13. #13
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default

    Quote Originally Posted by Beltdrive View Post
    I can't say for certain if the amps are the same between the X and A, the motors are different though.
    Under the cap on the servo motors is an encoder/resolver which are the same on DC drives.

    Normally we would check fuses and swap amps first.

    Then the encoder would be the suspect.
    And the motor last. (Most expensive and hardest to do.)

    The axis card could be at fault although I've never had to change one.

    I had a bad axis cable once that acted in the manner you described.
    It ultimately fried the motor before the problem was found.


    a mega ohm meter can help diagnose bad cables and motors.

    I've been running fadals for 20+ years now.
    In the last 10 I have been doing more and more maintence. Change motors, amps, encoders, spindles ect.
    There are 3 fadals in the shop, all have 4th axis, only 1 has DC drives.

    Tried swapping the amps - first, x and y, and the problem went with the amplifyer, after the swap, y axis had the problem instead of X axis.

    Then I got back in place all the amps, and replaced A axis amp and x axis amp, but the amp (A on the place of the X and vice versa) wouldn't work.

    Strange.

    I noticed that all LED's on amps are red for some time (except the one on x axis, it is not working at all), and then they turn green.

    Y axis amp does that first (that amp looks slightly different, I believe it has been changed by the previous owner).

    Anyway, I'll try to find some CNC maintanace expert to confirm my assumption about defective amp, because I don't have a 100% clean situation about it.



  14. #14

    Default Re: Servo brake problem

    If the problem followed the amp to the y axis then I would change the amp.



  15. #15
    Member
    Join Date
    Apr 2012
    Location
    serbia
    Posts
    49
    Downloads
    0
    Uploads
    0

    Default

    Quote Originally Posted by Beltdrive View Post
    If the problem followed the amp to the y axis then I would change the amp.
    I think so.

    That's what I am going to do. Got any link where I can find amps? Where I live, there are not many fadals...



  16. #16

    Default Re: Servo brake problem

    https://www.kmac-parts.com/product-category/amp-boards/

    I've used these guys recently as a month ago for a spindle encoder.



  17. #17
    Member FadalCNC_Com's Avatar
    Join Date
    Aug 2018
    Posts
    21
    Downloads
    0
    Uploads
    0

    Default Re: Servo brake problem

    Ginner,

    If the amps don't look the same between your A and X, Y, Z don't try to use it in exchanging amplifiers. First, disable your A axis in the parameters and put the dummy plug in the socket mounted on the upper right hand of your machining envelope. Now, turn the machine back on and see if you are still getting an alarm on the X axis. If so, exchange your amps. X for Y and see if the problem moves or stays with the axis. If it moves, you have a bad amp. If the alarm stays with the X axis, try exchanging the X for Y controller cards and try again. Make sure you know how to exchange the cards. If you have anything but the 1010-6, you will need to move jumpers from the boards and exchange them. I can send you a procedure if you need one. Again, if the problem moves to the Y axis, you have a bad controller card. If it stays with the X axis, remove the motor from the ballscrew and lay it on the table. Try to move it again. If it moves normally, definitely checking the ballscrew would be next. Like stated in an earlier post, it must move very smoothly, if it doesn't move, you found your problem. If it moves okay, now try exchanging the X motor for the Z motor and see if the problem moves with the motor or stays with the X axis. If it stays with the X axis, you have something in your motor causing it to be DOA. Meg it and see if you have a short to the motor casing; likely from carbon dust. We offer meggers on our Tech Tools page. You can clean the motor, replace the tach, bearings and resolver or just buy a reman or new one. We have both in stock if needed.

    FadalCNC Tech Support



Tags for this Thread

Posting Permissions

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


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Servo brake problem

Servo brake problem