flow valve

[srd]

Hi All, we have a 4-20ma motorised valve we need to control to allow 63 l/s through, we have a 4-20ma / 100 l/s flow paddle on the pipework. I would like to have a go at doing a pid circuit to operate the valve. Would anybody have any examples or guidance preferably in LD or FBD they could let me look at or show me how to do it. We have an easy with an analogue module to use. Thank You

[radar17892]

Hi srd,
A small example using a PID controller.
The parameters are stored permanently in words 33-37.
I recommend starting with the following values:
KP=70;
TN=3.0s;
TV=0.8s;

To calculate the parameters, you can analyze the step response of the controlled system. There are various tutorials on this in the field of control engineering.

Thomas

[srd]

thanks for that it looks like what i need.