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JP5 - max output frequency

Posted: Sat Sep 18, 2021 10:49 am
by cemoa9
Hello Tom,

Trying to mill the first part with kflop, I found a new issue, I have a spindle controller driven in step/dir, 2500pulses / rotation, but after 2700rpm the spindle would just stop and driver would say no pulse received. I checked with an osciloscope, signal is clear until 2700RPM, but would be just noise from 2800rpm.

Remembered then the pulse length set-up, but if I set it too low (to reach the 8000rpm of the spindle) then the X-Y drives will not work, can it be set-up by channel?

Cordially

Francois

Re: JP5 - max output frequency

Posted: Sat Sep 18, 2021 3:23 pm
by TomKerekes
Hi Francois,

No there is one setting for all Step Generators. Do any of the Drives accept quadrature input mode? Depending on the mode and interface you are using adding a 5V driver to the signal may help.

Re: JP5 - max output frequency

Posted: Sat Sep 18, 2021 3:41 pm
by cemoa9
Hello Tom,

The spindle drive accepts AB inputs, but I do not really understand what you mean with 5V driver. :oops:

Cordially

Francois

Re: JP5 - max output frequency

Posted: Sat Sep 18, 2021 3:45 pm
by TomKerekes
Hi Francois,

AB quadrature should work better. There is no pulse width associated with this. Each edge cause a step and the frequency is half what pulses would be. Set the pulse width longer for your other drives.

Re: JP5 - max output frequency

Posted: Sun Sep 19, 2021 2:54 pm
by cemoa9
Hello Tom,

Works perfectly.

Thx

Re: JP5 - max output frequency

Posted: Tue Oct 19, 2021 9:19 am
by cemoa9
Hello Tom,

Playing with the programs to shorten the tool change I noticed a strange behavior, sequence performed is :

JOG spindle 1000
JOG spindle 0
Reset Spindle ON Bit
Perform SPINDLE HOMING (Done by spindle controller)
Set Spindle ON Bit

and when setting the position Bit the spindle would go fast without command, and no destination change in Kmotion.

I checked the signal and made a video :

https://drive.google.com/file/d/1bB2ikE ... sp=sharing

We see an ok signal for the JOG 1000, the nothing for the JOG 0, but then comes a smaller signal for a short period.

Any idea of what it is? (Noise from the Spindle drive?)

Cordially

Francois

Re: JP5 - max output frequency

Posted: Tue Oct 19, 2021 4:24 pm
by TomKerekes
Hi Francois,

I don't fully understand what you are doing or what signals you are referring to, but if you disable the Servo Drive, move the axis to cause a large difference between the commanded Destination and measured Position, then re-enable the Servo Drive, the huge error will cause a violent motion to attempt to drive the Position back to the commanded Destination. The KFLOP Axis should be disabled while the Servo Drive is disabled, then re-enabled setting the Destination to the new Position. ie for axis 3:

EnableAxisDest(3, ch3->Position);

Re: JP5 - max output frequency

Posted: Wed Oct 20, 2021 9:17 am
by cemoa9
Hello Tom,

You guessed well, works fine with your solution.

Thank you.

Francois