Need Help! Warner/Swasey QCM-6 lathe with Kflop/Kanalog - Page 4


Page 4 of 13 FirstFirst 1234567 ... LastLast
Results 61 to 80 of 254

Thread: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

  1. #61
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Charles,

    That does seem like a lot of variation. Tachs are normally DC similar to a DC Brushed motor. If it has commutator brushes it is very likely DC. AC reading might be noise caused by the 240V Motor switching nearby.

    Regards
    TK http://dynomotion.com


  2. #62
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Tom.

    If it turns out my tachs are bad, what are the implications of running without them, using the encoders to complete the loop?

    Thanks
    Charles



  3. #63
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Charles,

    If it turns out my tachs are bad, what are the implications of running without them, using the encoders to complete the loop?
    Its hard to say for sure as the Amplifiers weren't designed for current mode. But most likely the amplifier commands current proportional to velocity error, so with no tach the input voltage will directly be velocity error and so directly control current. It may have a small range as a small velocity error of say 1V might try to apply full current depending on the tuning and internal gains. I think it is worth a try. Ideally the amplifier should be tuned so that full voltage (10V) applies full current/torque.

    Regards
    TK http://dynomotion.com


  4. #64
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    I'm not giving up yet. Waiting to hear from Mike on my latest results. I cut the wires at the tach to eliminate the cable. Turning shaft by hand, resistance across tach wires varies from 1 or 2 K ohms to 100 ohms, with the highs at say 12,3,6,9 o'clock and lows in between. The X tach is 5-24 ohms.



  5. #65
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Tom. I'm back at it again. I think I have the drives and tachs straightened out. Before I get back to the tuning, I have a question about the drive enable circuit. I want to keep the drives disabled until the CNC is completely up.

    It sounds like the SWE terminal on Kanalog JP8 is what I need to use. I have added a small 24 volt relay to switch the drive enable relays. Is it safe to sink outside 24 volts through SWE?

    Thanks,
    Charles



  6. #66
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Tom, I do have a 12 volt relay. Would I be better off to use it and the onboard 12 volts to keep outside power away from KFLOP?
    Thanks,
    Charles



  7. #67
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Charles,

    If you haven't already you might read:

    Relay Drivers / Grounding

    and

    Drive Enables - Axis Drift with Servo Disabled - Power up Issues

    and

    Logical "AND" of Opto Output and Relay Driver

    HTH

    There isn't really any "onboard 12V". I don't think it matters regarding using an external power supply or otherwise. The issue is that the supply should be used locally (close to KFLOP/Kanalog) and not be common ground with the supply that is used for the opto isolated circuits that run all over the machine for limits and such.

    Regards
    TK http://dynomotion.com


  8. #68
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Tom,
    After reading the above, I remembered that I have a few 3-32 volt solid state relays. Connected one to the 5 volt terminal and SWE on Kanalog JP8. It switches the 24 volt relays for spindle and axis drive enable. It works great. Delays drive enable until Kflop is up. The 24 volt relays are in the E-Stop circuit.



  9. #69
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Tom,
    I hope you have plenty of patience left, and are willing to help me as I struggle to learn tuning. I keep rereading your earlier responses to me and to others, notably PetertheWolf. I also keep rereading the wikis and everything else I can find.
    It is starting to seem less daunting.

    One of my many problems is that I'm not getting the same results as others. I am still not sure my drives and tachs are performing correctly.

    I have been able to get my P gain up to 1.1, and above, without oscillation, if I keep the D gain at around 375. Is that reasonable for D gain to be so high?

    If I change the step size higher than 10000, I get diagonal line on the graph, with waves.

    If I send DAC commands, like 164, I get -.80 volts on Analog screen, and 220 RPM. I get proportional results up to DAC1=500, 2.44 volts, 620 RPM. All moves are smooth and steady. Ran tests + & -. All about the same results. This is with servo disabled.


    Now, here's where I'm confused. If I try JOG commands, with servo Enabled, of 66667, Analog screen shows 2047 DAC, 9.995 volts, and it's about 250 RPM, but surging badly. It's like it's maxing out, pausing, and maxing again.

    That was all Z axis. With same settings in X axis, I get similar results.

    It looks like DAC commands, with servo Disabled, are about right, but JOG commands with servo Enabled, are unstable, if that's the correct term.

    I know it's probably something I'm doing wrong.

    P=0.8, I=1e-05, D=375, limits=2047, 2500, 100000
    Profile=40000, 400000, 4e+06
    Feed fwd= 0.045, 0.0025
    DB= 0,1
    Step size= 10000

    Thanks,
    Charles



  10. #70
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Screen shots:
    This is my latest Z axis graph with Step size at 10000.

    Warner/Swasey QCM-6 lathe with Kflop/Kanalog-stepresp12-png

    This is with Step size at 100000. Machine motion is very similar to the above described JOG commands.

    Warner/Swasey QCM-6 lathe with Kflop/Kanalog-stepresp13-png



  11. #71
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Charles,

    It is starting to seem less daunting.
    That's good!


    I have been able to get my P gain up to 1.1, and above, without oscillation, if I keep the D gain at around 375. Is that reasonable for D gain to be so high?
    Seems high. Normally values are 10-100X the P Gain. Hard to say? Please show us your Filter Screen also. It's helpful to post the raw data so we can re-plot. I think cnczone has a 1MByte limit. Zipping or reducing the time usually gets it under 1MByte,


    Now, here's where I'm confused. If I try JOG commands, with servo Enabled, of 66667, Analog screen shows 2047 DAC, 9.995 volts, and it's about 250 RPM, but surging badly. It's like it's maxing out, pausing, and maxing again.

    That was all Z axis. With same settings in X axis, I get similar results.

    It looks like DAC commands, with servo Disabled, are about right, but JOG commands with servo Enabled, are unstable, if that's the correct term.
    I think this is classic instability. Theoretically if a system is linear if it is stable at rest it should be stable while moving, but nonlinearities like friction can be non-linear. I think you will need to reduce P I D Gains until it is stable at all speeds. I'd set I to zero temporarily to see if that is the issue. Then reduce P Gain.

    I suppose it could be a quirk with the amplifier. Things might be clearer once you can do long stable moves.

    Commanding DACs is open loop without feedback so it will never overcorrect and become unstable.

    Regards
    TK http://dynomotion.com


  12. #72
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Tom,
    I took the P gain down to 0.12 and D down to 90. D still seems high, but much lower and P has to be set lower. In this range I can move at 10000 or 100000 with stability. I can't seem to get the lines to come even close to overlapping. I have tried many combinations, including feed fwd and motion profile. With several parameters involved, I feel like I'm trying to open a combination lock without the code. Sending screen shots and data. Please help!

    Thanks,
    Charles



  13. #73
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Latest Screenshots and data:

    Warner/Swasey QCM-6 lathe with Kflop/Kanalog-filter14-png

    Warner/Swasey QCM-6 lathe with Kflop/Kanalog-stepresp14-png



  14. #74
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Data file. Limit is 500K. Ran at 1 second time.

    Attached Files Attached Files


  15. #75
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Hi Charles,

    Looks odd.

    It appears the tach is not doing much. If it were the green plot would correspond to velocity (slope of red Position plot). But instead it more corresponds to acceleration (curvature of red Position plot). A longer move with more constant velocity would help clarify that.

    But that shouldn't necessarily be a problem. If the amplifier commands acceleration (torque actually) quickly it should just need D Gain to stabilize it. But needing D Gain ~ 900X P is strange.

    There are two ways to implement D Gain. One is to apply it to the Position the other to Error. KFLOP applies it to Position. You might see this. This is like adding artificial Drag. At a velocity of 40,000 counts/sec and D = 90 the drag is:

    40000 x 90 x 90us = 324 DAC counts

    To overcome this much Drag with basically only small P Gain a significant error is required:

    324 / 0.12 = 2700 encoder counts of error which is about what we see.

    Velocity Feed Forward can be used to compensate for the Drag and make it equivalent to applying to error. Set it to D x 90us to compensate. In this case it would be:

    90 x 90e-6 = 0.0081

    Please try this to see where we are.

    Regards
    TK http://dynomotion.com


  16. #76
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Screenshot:

    Warner/Swasey QCM-6 lathe with Kflop/Kanalog-stepresp15-png



  17. #77
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    A little better. Any idea why the asymmetry? Takes ~150 DAC couts to move positive, but ~450 to move negative. Seems to have gotten stuck? Is this repeatable?

    Regards
    TK http://dynomotion.com


  18. #78
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    Seems to repeat at ~150 to ~-350. Earlier plots didn't seem to be this way. If I take out the velocity Feed fwd, it is more balanced.



  19. #79
    Member TomKerekes's Avatar
    Join Date
    May 2006
    Location
    USA
    Posts
    4043
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    The Plot in post #70 seems to have gotten stuck first moving positive. I'm not much of a mechanical person. What kind of a machine is this? I assume very big? Could it have binding or stiction? It might be position dependent. You might try tests at different positions of the axes.

    Regards
    TK http://dynomotion.com


  20. #80
    Member
    Join Date
    Jun 2006
    Location
    USA
    Posts
    194
    Downloads
    0
    Uploads
    0

    Default Re: Warner/Swasey QCM-6 lathe with Kflop/Kanalog

    This is a Warner & Swasey QCM-6 (M-5100). Small machine, very well built like a much larger W/S. Granet bed and headstock. 1984 vintage. I was told by one of the original W/S guys that it was intended for tool room service. Has about 8 inches X travel and about 11 inches Z travel. 2.5" round Z wayrods, 2" X wayrods. Bijur pressure lube. Fibrotakt (German) air operated 8 position turret. Hydraulic drawbar, 2-J collets, Whitnon spindle, A2-5 spindle face (I think). Came with a GE2000 control (for sale). Has about 400 hours on the clock. Slides (wayrods) have seals and ballscrews have bellows, but it all appears to be oiling well.
    Will check movement at different positions.



Page 4 of 13 FirstFirst 1234567 ... LastLast

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

Warner/Swasey QCM-6 lathe with Kflop/Kanalog

Warner/Swasey QCM-6 lathe with Kflop/Kanalog