Hello all, this is my first time posting here. I'm a chemical engineer trying to characterize the closed loop dynamic response of a device in my lab. I've made progress, but one of the last outstanding questions is whether or not the controller within the device is PI, or PID. Fortunately I'm armed with the circuit diagram (relevant part attached), so theoretically one should be able to look at it and say whether it's PI or PID. Having very little experience with circuit design, I'm hoping there's someone out there that can help me settle this.

From the circuit, I'm almost certain that this is just a PI controller. Does anyone feel comfortable confirming that? Is more info needed?

Thanks for your help!

 

Welcome to AAC

First, try posting the whole diagram instead of a partial ckt.

 

Yes, I see no obvious D in what you posted.

But that's an odd circuit with a capacitor going from the summing junction to ground.