How can the PID block in the Yokogawa DCS be forced to output 0 automatically or to a specific value?
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I would like to conduct such an experiment: after pressing the start button for 3 seconds, valve A controls the liquid level for 20 seconds, after which valve A is closed and valve B controls the liquid level for 10 seconds. At liquid level HH, AB closes and the outlet valve opens. When the liquid level is at LL, valve A is opened for circulation; how can the MV value of valve A’s PID be forced to 0 after a certain time has passed? Thank you. Also, what is commonly used to make the DCS start/stop buttons? Internal switch? PBS5C？ Thank you!
I use PID for valve control, not digital on/off control.
It seems that in logic, the output is denoted by tagname.psw.0; if a specific value is required, there is a tracking function available in the PID module. For buttons, soft switches can be used directly – buttons on the screen can be connected to these soft points to enable or disable certain functions. The PBS5C can also be used for this purpose, especially when there are more than three buttons, such as for start, wait, and stop functions. I’ve forgotten a lot of it; I need to review it when I have time: lol
In sequential control: PID MAN, MV.0