Foxboro Pid Manual
In many plants, process engineers are guessing PID tuning numbers. The outcome of guesswork is increased wear on valves, shortened valve life, poor control, and inconsistent results.
When you eliminate the guesswork, proper tuning will stabilizes the plant, improves reliability of valves, and makes it easier to sleep at night. Focus your efforts in the right place - instrument and valve issues are easily distinguished from tuning problems.
Tune with confidence – Accurate tuning parameters for the process response that you want. Reduce mistakes - no math required. PID Loop Optimizer knows your controller, its algorithms and all the unit conversions. Speed up your loop tuning activities, tuning many loops in one day.
You have total control over the tuning selection – whether you want fast response or slow ramping. Tune specialized loops, like pH control, level controllers, cascade and more.
Foxboro Pid Controller
This block implements the PID control equations found on page 1680 of the Foxboro I/A Series Integrated Control Block Descriptions Manual Volume 3, dated May 31 2006. Use this block when the target platform for a PID control design is a Foxboro I/A Series DCS.
These blocks have been field verified by the author and are designed to be directly compatible with the Foxboro equivalent PIDA blocks. Depending on the level of interest, the block may be developed in the future to add further functionality. Dear Paul and other expert who read this comment, last year I was happy with your explanation and implementation of the PIDA simulink model. Now we have a little more complicated situation: we need to model the PIDA behaviour in output limitation and recovery from the limit. This came up with overide control implementation using two PIDA and one OUTSEL blocks. The'd like to better understand the three LIMOPT versions and generally the antiwindup algorithms implemented in PIDA.
Any hint will be highly appreciated. Gunter Reinig. Hi Gunter, It's been a while since I developed and used these blocks. From memory the main difference between the I/A Series PIDA Block and the Mathwork's/other PID implementations is with the treatment of the derivative.
Foxboro Pid Tuning
The I/A Series PIDA block dates back decades to when pressure control signal systems were commonplace and there was a need to subdue rapid changes in pressure signalling. I don't have the details on me right now about the performance of the block in anti-windup and output limiting modes, but if you have a basic plant model available you could certainly test this out by making a comparison (this was the primary reason for me developing the block in the first place). I hope that helps.