Dynomotion Forum

I have setup the spindle in my machine. I'm using 2 bits to control direction and stop (M3,M4,M5) and have S setup correctly. Now I wanted to test the spindle's speed control. When I press ON CW in KmotionCNC, the spindle goes full speed, ON CCW will change the direction and again it goes into full speed. When I try to change the spindle speed to lower it using the slider , nothing happens at all. When I manually send the G-Code to set the RPM , the spindle is then set to the correct RPM. Whenever I press OFF it stops, but I see the DAC output remains at the last set value, it is never set back to 0.

I assumed that I can control the spindle speed directly with the slider but nothing I do works. Is there anything I'm supposed to enable in order for that slider to work, or , does it only work when KmotionCNC is really running a job? Should I worry that the DAC doesn't return to 0 when the spindle is set to off?

Any help is appreciated!

Hi Roamin,

The Slider for Spindle Override is a relative thing. The S RPM value has to be set with an S Command first. The number next to the Red S is what the current S setting is.

Should I worry that the DAC doesn't return to 0 when the spindle is set to off?

The DAC value shouldn't matter when the Spindle is off.

You might read this.

Thanks Tom for the fast reply! The document you linked is what I used to setup the spindle. Setting the S RPM with the S command does indeed work. For example I set it to 200 RPM down from the default 1000 RPM , but even once it was set by this command , the slider didn't work. The top number next to the red S reflects the 200 RPM set by the command but the number below always reads 0. Can you tell me if the slider should work after I turn on the spindle with the ON buttons? I did not run an elaborate G Code to try the speed change while it's running as I'm still in the testing phase of our conversion.

Hi Roamin,

For example I set it to 200 RPM down from the default 1000 RPM , but even once it was set by this command , the slider didn't work.

What happens?

The top number next to the red S reflects the 200 RPM set by the command but the number below always reads 0.

The second number is the measured speed. If there is no encoder on the the spindle connected to KFLOP then it will read zero.

Can you tell me if the slider should work after I turn on the spindle with the ON buttons? I did not run an elaborate G Code to try the speed change while it's running as I'm still in the testing phase of our conversion.

After you set the S to 200 and turn on the Spindle the Spindle should run at 200 RPM if the SSO is set at 1.0. If the SSO is changed the Speed should change.

Hi,

I did more tests with the SSO and still nothing changes. I took some screenshots and mashed up a picture for you. The very first line is how my S is setup in tool setup screen. Underneath is the S1000 command , S set to 1000 and the DAC value. Underneath is S100 command , but the DAC remains at the same value (-2047). Nothing I do here , lowering the slider to 0.15 and hitting apply , the DAC will never change value. (The spindle reacts properly when I manually set the DAC in the console). The last part is when Kflop is running the default GCode found in sheet 1. It sets the speed to 200 but the DAC doesn't change either. Using the override doesn't change anything.

Thanks for your help!

Hi Roamin,

I think the issue is you have the Scale set at -2047. This means that a command of 1RPM the output will be -2047 (10V). Divide the -2047 by whatever speed your spindle runs when commanded to full 10V. For example if the full speed is 1000 RPM then the scale would be -2.047

Well.. I don't know what to say.. If only I took more time to read the documentation properly. I read and re-read the "Basic Configuration" paragraph a few times but I had not noticed the period in the scale.. My calculations were based on 1000 RPM but I just entered "-2047" instead of "-2.047". Although that paragraph doesn't mention dividing the scale by the RPM , it clearly states -2.047 .. -> "Note the S action is mapped to Kanalog DAC #7 with a negative scale of -2.047."

Again , thanks a lot for your help! I spent the day chasing other issues, like understanding how to have the table & position count in the right direction (I had to invert both input and output gain to fix the direction/position relationship).

We are getting closer everyday to get that Fanuc 5M running on K-Flop. The tachometer signal from the motors is probably what stalled us the longest since the original control board sometimes freezes and stops producing the tach signal so the original idea of leaving control board to generate the tach until we decided to generate it with the Kanalog.

I will check the scaling issue as soon as I can tomorrow , once I've re-assembled the covers around the spindle. I will post back after but I'm guessing this issue will be solved as well. Many thanks!

I confirm that adjusting the scale properly gives me control over the spindle speed with the slider..

Thanks!

**Goes back to hiding in his hole