. .
Page 1 of 3 123 LastLast
  1. #1
    Have owned a KX3 for some years now and I'm having no spindle rotation for the second occasion. The provblem was sorted by the late John Stevenson and at that time I replaced the spindle motor control board. The problem has happened again and going through the same test proceedures as before I find that I am not able to get anywhere 10 volts out of the breakout board. I have tried changing step pulses, pulleys and have the voltage adjuster turnned up full and can only get 4 volts. Is my problem in the breakout board this time or is it the motor control board again. X,Y & Z are working normally.

  2. #2
    We need more info. I'd guess the BOB generates the isolated 0-10v and feeds this to the Spindle control board which I'd guess is a DC motor controller.

    However, I'm guessing so it would be best if you could give more info and post pics of what's inside.! . . . . . Or because Basic BOB's are so cheap these days just swap out the BOB.!

  3. #3
    Hi Jaz
    Yes the 0-10v comes from the BOB in the right hand side electrical compartment and then goes to the DC spindle control board in the rear compartment. All the works are as the standard Sieg KX3. I'll take some photos and post them to-morrow.
    Thanks
    Ken

  4. #4
    Quote Originally Posted by ModelSteamKen View Post
    Hi Jaz
    Yes the 0-10v comes from the BOB in the right hand side electrical compartment and then goes to the DC spindle control board in the rear compartment. All the works are as the standard Sieg KX3. I'll take some photos and post them to-morrow.
    Thanks
    Ken
    Ok well that's simple enough to check. Disconnect the wires going to the Spindle control board and measure the voltage at commanded speeds. If you haven't changed any of the Spindle settings in control software (mach3 I presume) then you should get 10v at full commanded speed. If you don't then it's the BOB at fault not the spindle control board.
    If you have changed the spindle settings then I can't help anymore without knowing the BOB your using, but Knowing John S it won't be anything too fancy as he liked to keep it simple and cheap.

  5. #5
    Hi Jazz
    Having problems putting a photo on but have checked the voltage and only getting 3.9v at full command speed. All setting are at original settings.seems like it is probably is a BOB fault.There is an web site visible on the board www.cnc4pc.com. Any other suggestions as to a make of board.
    Ken
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	DSC_6391221_223_.JPG 
Views:	236 
Size:	470.9 KB 
ID:	27579  

  6. #6
    Good old John S probably just saved you some money by fitting decent gear.?
    I think that's old or should say, early C11 board.? If you notice the board is full of plug-in chips rather than surface mount like many cheaper boards use, this is done so can easily swap them out if one blows up.

    Cnc4pc is owned and run by a guy called Arturo who's a very helpful guy so maybe worth dropping him an email. He'll tell you which chip you need and more than likely sell you one.

  7. #7
    The picture isn't great but it looks to me like there's a group of 3 capacitors near the center of the board and the middle one looks like it's blown.? I'm not into electronics but I'm pretty sure something like this would still allow to work but lower the voltage.? . . . I'm sure Doddy or some of the Electronic wizards will tell you quickly enough if it can.

    It may be worth you taking it out and giving a close inspection.!

  8. #8
    Hi Jazz
    Thanks for the info I'll try and get in contact with Arturo at cnc4pc.
    Ken

  9. #9
    Clive S's Avatar
    Lives in Marple Stockport, United Kingdom. Last Activity: 20 Hours Ago Forum Superstar, has done so much to help others, they deserve a medal. Has been a member for 9-10 years. Has a total post count of 3,333. Received thanks 618 times, giving thanks to others 78 times. Made a monetary donation to the upkeep of the community. Is a beta tester for Machinists Network features.
    Quote Originally Posted by ModelSteamKen View Post
    Hi Jazz
    Thanks for the info I'll try and get in contact with Arturo at cnc4pc.
    Ken
    Jon swift on this forum seems to collect a lot of bob schematics and might be able to help.
    ..Clive
    The more you know, The better you know, How little you know

  10. #10
    Quote Originally Posted by JAZZCNC View Post
    looks to me like there's a group of 3 capacitors near the center of the board and the middle one looks like it's blown.?
    Pfft, you have better eyes than me.

    I did google the KX3 when Ken first posted - I think I agree with the C11 board and this was the original spec for the machine so a like-for-like replacement at the time? A new card is (only?) $68 and if OP has the confidence to replace then it might be the easiest solution all around. The chip that's going to be responsible for the analogue output is the LM<something-or-other> on the far left of the photo. That's likely a £1 replacement, though it could be with the ancillary circuitry around there (caps, resistors) or the opto-isolator (the white chip), or the power from the spindle-controller card (I'd expect that to export 12Vdc to the BOB for the purpose of isolated power supply between the BoB logic and the spindle-controller) - worth checking that.

    OP: If you find yourself in a rabbit hole with this (and I don't think you need to) if you're prepared to post the board I could always take a look to overhaul it. That's a casual offer - I think it'd be quicker/easier for you to contact CNC4PC in the first instance.


    EDIT:

    Just re-reading the thread, OP - if you have the 10V supply from the spindle board then try throwing a 10k potentiometer across this and the spindle 0V, with the wiper connected to the analogue input - that should give you full manual control of the spindle speed and verify that the spindle board is okay - just to confirm the BOB is suspect. (there's a chance of a fault on the spindle board dragging the analogue output from the BOB down - this just helps to isolate the problem).
    Last edited by Doddy; 15-03-2020 at 10:25 AM.

Page 1 of 3 123 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Replies: 6
    Last Post: 20-12-2018, 03:40 PM
  2. Seig C3 CNC spindle problem
    By Leadhead in forum Machine Discussion
    Replies: 11
    Last Post: 15-08-2018, 08:12 AM
  3. Huanyang VFD and spindle problem
    By BriceO in forum Spindles & Drive Motors
    Replies: 20
    Last Post: 07-08-2018, 08:56 AM
  4. Problem with Spindle not spinning
    By Noplace in forum Spindles & Drive Motors
    Replies: 4
    Last Post: 22-01-2016, 02:40 PM
  5. CNC spindle control VFD problem
    By djc in forum Motor Drivers & Controllers
    Replies: 1
    Last Post: 13-09-2009, 09:26 PM

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
  •