A question on PID control in the Emerson Exchange 365 community reminded me how good some of the free, online learning tools are available for engineers new to our instrumentation and process automation ranks. The question:
i have a question about PID, about setpoint for one pid from other pid ,,,is possible that these two pid are in deference type? for example :HIC x makes setpoint for FIC x
Community member Youssef.El-Bahtimy responded:
Take a look at this www.controlloopfoundation.com/cascade-control-exercise.aspx
And in books on line the article on PID function block application information
www3.emersonprocess.com/…/c_pid_function_block_application_information.html [Foundation Support login required]
What are great about the site are the workshops, or interactive simulations that you can run to learn the concepts.
Workshops include:
- Process Characterization — Exercise One, Two, or Three
- Feedback Control
- PID Tuning
- Feedforward Control
- Cascade Control
- Override Control
- Split Range Control
- Valve Position Control
- Ratio Control
- Model Predictive Control
- Process Simulation
Each of these workshops have sections that explain the exercise to be done in the workshop, the process, the workspace where you can simulate the process and control loop responses, a trend chart with the key variables and a video of Terry narrating how to work through the exercise. So specifically for the PID question above about cascade control, here are the links to the tabs:
On the Solution tab, here’s the almost 10-minute workshop YouTube video as Terry explains how cascade control works and looks when implemented in a DeltaV system.
Thanks Youssef for reminding me and other community members of this wonderful freely available site to help learn basic process control concepts. There’s also a Kindle version of the book available for a deeper understanding of the concepts to increase your knowledge depth.
You can connect and interact with other members of the Emerson Exchange 365 community by joining one or more of the many groups in your areas of expertise.
