KFlop Kanalog and DMM

Has anybody used DMM servos with KFlop and Kanalog? Did you use the DYN2 or 3 servo drives or the SnapAmp?

I am trying to understand what the tradeoffs would be between using the DMM drive (presumably simpler setup, tuning and auto tuning) vs having all the control elements in one system, particularly concerning ridged tapping..

The application is 3 axis for a mill upgrade (http://www.cnc-arena.com/en/forum/ex...e--254025.html). Will likely wind up with the 750W motors (86M-DHT-A672). Cost wise, there does not seem to be a big difference between the various approaches and will still get about 120ipm with SnapAmp or DYN2 on the 750W motors which is probably sporty enough for an old guy...

Thanks,

Bruce

BruceGuest

For rigid tapping it is all about spindle encoder & how that is controlled, either Dmm Drives should work well for your machine, if you use step/dir, this is the easiest to set up +/- 10v will be more difficult to set up, but both will work

I don't know of anyone using KFlop and Kanalog that have the Dmm system, There most likely is some users though,they should work very well, you should be able to get more than 120 ipm, depending on your Ballscrews gearing, if any Etc

mactec54

What is the specific advantage of controlling the Z servo in position mode vs speed mode for rigid tapping? Would the Z not become a slave to the spindle position as indicated from the spindle encoder?

As i understand the KFLOP/Kanalog setup, in order to get step and direction outputs the differential encoder inputs (which is what the DYN drives provide) are unavailable on the Kanalog. Instead the single ended encoder inputs on the KFLOP are used which requires a converter (not a big deal, just have to plan for it).

Thanks,

Bruce

Hi Bruce,

I don't think there is any advantage to controlling the Z axis in Step/Dir mode vs an Analog Servo Loop. As long as KFLOP can control the Z position so that it can track the spindle motion it should work for rigid tapping. Some Users might find Step/Dir preferable because they prefer to close the position loop in the drive rather than in KFLOP.

There are ways to make use of KFLOP's Step/Dir Outputs and still use Kanalog and have most if not all Kanalog differential encoder inputs available. I can provide more details if needed.

HTH
Regards

Hello Tom,

Thanks for the reply. I am probably agonizing over subtle details when i should really be trying to gain a better understanding of the basics. Is there a direction or source you could point me towards in order to better understand the different types of servo control in the context of CNC applications?

My sense is that it would be best to close the position loop in the KFLOP so that all the motion control is in one place. Are the motion control algorithms compromised in any way if one type of servo control is used vs another?

Thanks,

Bruce

BruceGuest

It will depend on what you want to run, a cnc Machining Center or Turning Center or a Router, as to what kind of control & servo system that will work best for you

It is always better to close the loop in the control,most good servo drive will have the Encoder feed from the servo motor to the servo Drive then the servo Drive to the control