I have a control valve(spring loaded, air controlled) that is normally open (air to close). My PID tuning is such that there isn't much Kp at all, and that the Ki is doing most of the work.
It works great, except that at process startup the valve starts from wide open and slowly closes because of the Ki. I want the opposite, I want the valve to start closed and slowly open.
Ideally there would be a normally closed valve installed, but I'd like to see if I can address this with programming. Has anyone dealt with something similar, and if so could you point me in the right direction?
Thanks,
Adam
It works great, except that at process startup the valve starts from wide open and slowly closes because of the Ki. I want the opposite, I want the valve to start closed and slowly open.
Ideally there would be a normally closed valve installed, but I'd like to see if I can address this with programming. Has anyone dealt with something similar, and if so could you point me in the right direction?
Thanks,
Adam