Control: perceptions versus reality May 2000, System Integration & Control Systems Design When starting in-plant control courses I always ask the class members to give me their individual estimates as to how many of their loops they believe to be operating satisfactorily in automatic. In a ...
Read more...Unusual control loops in a chemical plant April 2000, System Integration & Control Systems Design During in-plant courses on practical process control the most interesting part of the course is always the last few days which are spent optimising live loops in the actual plant. Even with a powerful ...
Read more...Another valve with weird characteristics March 2000, System Integration & Control Systems Design Figure 1 is the open loop test on the flow loop. It should be noted that as the valve appeared extremely linear with a nice fast response and was hysteresis free, the test was only conducted over a flow ...
Read more...Faulty positioner causes instability Jan 2000, System Integration & Control Systems Design
In a recent course held in a South African chemical plant, a loop was encountered that cycled continuously. The loop was a pressure control that was acting as the slave (secondary) loop in ...
