I had mentioned in an earlier post that short screencasts are a great way to quickly convery ideas in lieu of hundreds of words. One of Emerson’s product application specialists, Rune Reppenhagen, graciously agreed to demonstrate how advanced diagnostics can be used in automation system control strategies.
Today’s example shows how air in a fluid can impact Coriolis flow measurement and cause the automation system control strategy to falsely assume it needs to increase the speed of a pump to try to raise compensate for the low flow measurement. This situation called entrained air or slug flow causes the measurement on the coriolis meter to go to zero. The actual flow is OK but the problem is with the measurement.
Rune demonstates in this screencast (runtime: 4:51) how advanced diagnostics like those found in Micro Motion Elite mass flow and density meters can be configured in systems like the DeltaV system to read these diagnostics and take action in the control strategy to turn the loop to manual control for the operator and notify him of the cause of the situation.
This immediate recognition of a process problem and operator notification of the situation is one example of how advanced diagnostics and digital communications protocols like Foundation Fieldbus provide ways for process manufacturers to avoid losses in production, quality excursions, and abnormal situations which can impact the efficiency of the production process.
