Quote Originally Posted by Jonathan View Post
Can you provide an exact model number for the servo-drive and motor? Does it allow you to adjust the PID constants as that will affect the response time, but could have a detrimental affect in other areas.

What are you using to signal the drive to move the motor this distance? The acceleration setting, if there is one, may be too low. Neglecting acceleration 1/20th of a turn in 15ms requires only 200rpm. Perhaps there is some other delay in the system lowering the response time. How are you measuring the time?
Thank you so much for answer Jonathan.

1-Servo motor is Yaskawa (Japan) SGMAV-04ADA61

2-Servo Drive is Yaskawa (Japan) SGDV-2R8A01A
I'm sending pulses with a board of my design. That board apply aceleration and desaceleration ramps, although, you can avoid them using Pn216 and Pn217 parameters of the drive. I'm sending the pulses enough fast to get a position time lower that I need. I'm using pulses/dir config, and open collector scenary for them. I also have other motors in the machine working well, doing different tasks, from 5.39Nm to 8.34Nm.


My servodrive in this case is for a 1.27Nm motor, I've run the SigmaWin software, and give me a inertia ratio of about 27 of the system, if I not remember well.
I did the tunning of the system while it was running in the real application, but I'd not good results.
Also I've change some parameters by hand, while doing some graphics of the time responses, the /COIN signal in the graphic report a position time of 15ms, but positioning error signal is more large, but in real time, looking at the motor, you can see clearly that is running so slow.
And the job that the motor should do, confirm that, I need more speed.

My application is a bit strange, I should move a wire, to be cut after the positioning, in a machine that get pieces of this wire at a specific lenght.
I should move only 25 pulses of the motor while it is set at 400 step/rev.

What I see, is: in that low quantity of pulses, I get a very low speed of turn, but,..... in example if move about 1200 pulses, then I get a positioning time about twice as the 25 pulses I get. That's what is getting me crazy.
I strongly need more and more instant aceleration, that the drive don't give me.
I can't believe that such a servodrive can't do the task, and a stepper that I have near, do it perfect.
Hope I was clear... English is not my natural language.

I've also adjust by hand the gains in some parameters without luck.
Also I've contact my Yaskawa distributor, but only said me that should work, not how

Thank you again.!!!