PID-Control

[Marco]

Good Morning wener_1,
thanks a lot for your example.
About your questions:

- the right divider was 4, but during the testing I tried to use also 1 as value.
- I subracted 200 beacuse the sensor is 4-20mA (0-100mbar), trasformed 2-10V (200mV-1000mV)

Thanks

[Marco]

Good Afternoon wene_1,
if I well understood, with VC (I1= DC QV, SH=1023, SL=716), I could regulating the valve from 70% to 100%.
So, I've just given the enable (EV) at the valve, it takes up itself at 70%.

Is it correct?


Thanks a lot.


Have a nice day

Regards

[werner_1]

What is "EV"?

I think, its correct.

At the transmitter you have 2...10V. Thats internaly 205 to 1023. If you now subract 200, you will have 5 to 823 for 0 to 100mbar. If you want to have 0 to 1000, you have to subract 205 and after them to multiplicate with 1,24.

[Marco]

Sorry.
(EN) not (EV).

Everything is clear.

Thanks.

Regards.

[Marco]

Good Morning,
I'm sorry to distub you again, but I would like to have more information about the right mode for calculating the PID components (KP, TN, TV, TC, MV).
Because, I want to know how to increase or decrease the answer's speed of the valve when the pressure changes.

Thanks.

Have a nice day.


Regards

[werner_1]

Hi,
please see here:

https://de.wikipedia.org/wiki/Faustformelverfahren_%28Automatisierungstechnik%29

[Marco]

Hi werner_1,
thanks a lot for your quick answer.

In my application KP is set in MW80, TN is set in MW81 directly from MFD-Titan display, TV is none and TC = 1.
If I supposed, at the beginnig, TN = 0, which is the first value for KP (0-65535)? 1, 10, 100?

Sorry for my very little knowing about PID.


Thanks.


Best regards

[werner_1]

Hi,

I'm not shure what's your question. 

For Kp=1 you have set KP to 100. But I think that is not your question.

Best regards
werner

[Marco]

Good Morning werner_1,
if I followed the Ziegler-Nichols as you linked I would have to set Kp=0.5Ku.
How can I find the value for Kp and Ku?
I should have to proceed step by step, I think.

For the DC function block, I should start with KP=50 (Kp=0.5 if I well understood) anf then with:

KP=100 (Kp=1)
KP=150 (Kp=1.5)
KP=200 (Kp=2)
......

Is the correct way to follow about your experience?


Thanks.

Have a nice day.

[Marco]

Hello werner_1,
I'm sorry to disturb again bt would like to know if the data written are correct [KP=100 (Kp=1), KP=150 (Kp=1.5), KP=200 (Kp=2)].

Thanks.

Have a nice day