parameters for PID gains

[steffi.kono]

Hi,

I have a question concerning the setting of the parameters for PID gains of the PID.vi.
I have my values for P, I and D in the following way:
P(1+1/(I*s)+D*s).
Can I now just enter these values for P, I and D in the cluster of PID gains or do I have to convert the values, for example for I: P/I? Do I have to enter the time for I and D in minutes?? (As the control of PID gains says for I for example: "integral time (Ti, min)" What does "min" mean?

Thanks a lot in advance.

Steffi

[TroubleTheShoot]

Hi Steffi,

I have looked into the function that you are using. The index "min" really stands for minutes. I got this information from the PID toolkit manual on page 3-17:

http://www.ni.com/pdf/manuals/372192b.pdf

On the following URL you can find explanations about the parameters and how to convert them from gain to time values or the other way round:

http://digital.ni.com/public.nsf/allkb/6E76EC47B831FAED86256E4E007347DC?OpenDocument

I assume that you are tuning a servo motor so I will post a last link that I find very helpful in this place:

PID theory explained:

http://zone.ni.com/devzone/cda/tut/p/id/3782

Understanding Servo Tune:

http://zone.ni.com/devzone/cda/tut/p/id/2923

Hope this helps.

Best regards,

David