Striplar (Customer) asked a question.
I'm using the Step & Direction inputs but the motors creep slowly back and forth by about 20 counts instead of holding a tight position.
I've tuned the drives manually using the buttons on the drive, I don't have any of the clever modern PC interface. I'm not sure that's even available for this older drive.
These are the parameters I've got in the X-axis SureServo which give a small following error and a crisp response without being unstable.
Could someone point me in the right direction to resolve the dithering about a stationary position?
Any assistance would be much appreciated.
X-Axis...
P2-00 110 Position Loop Proportional Gain (KPP)
P2-02 10000 Position Feed Forward Gain (KFF)
P2-03 5 Smooth Constant of Position Feed Forward Gain
P2-04 3000 Velocity loop proportional gain. (Used in conjunction with P2-25)
P2-06 70 Integral gain was 100
P2-25 15 Low pass filter. Increase just enough to eliminate noise
Want to update this thread since this issue is also being worked on with ADC technical support team.
Response from tech:
For Pt mode P2-00 and P2-02 are the ones to adjust mostly. It could be P2.00 is not set high enough and the load is moving the motor when trying to set still. It also may be set too high and causing an oscillation. You may just have to try some numbers and see how it works.
Response from @Striplar (Customer) :
OK, thanks for that. I've been playing with it for most of the day, and I'm pretty close to it being right now. It's especially sensitive because I'm using a KMotion motion controller to generate the Step & Direction pulses, and I've got Linear Encoders. So there's a loop within a loop, and that can unsettle the SureServo.
I'll see how it works out when I use it on a real job. Clocking up a part has been almost impossible with my first attempt because it was dithering about 30microns, even though I've got 1micron scales!