How to read a DCS diagram
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This post was last edited by guanjian88 on 2011-12-1 09:03. How to read DCS diagrams? Duan Duan each goes to the seafaring people to teach
Reply to 1# Hold Hands for Happiness: Do you mean the DCS screen that process operators use, or the DCS configuration screen that instrument technicians view? The operation interface for process operators is much simpler than the PID diagram. If you can understand PID diagrams, it should be no problem to understand the operation screens. To understand the DCS configuration screens viewed by instrument operators, one can only seek more advice from them and gradually build up knowledge over time.
One needs to become familiar with the process flow as well as the basic operations on the DCS; it’s necessary to learn how to read parameters, trends, interlocks, and more. There’s so much to learn – one should keep accumulating knowledge on their own.
First, memorize the process flow diagram, the interlock values at various control points, as well as the normal operating values and alarm thresholds. In short, to learn more, one needs to accumulate knowledge gradually.
The DCS diagram is the interface for process operators to work with. First, understand the PID diagram and memorize the process flow; then recall the interlock values, normal operating values, and alarm values for each control point, as well as what the parameters at those points mean. After that, learn how to carry out manual, automatic, cascade, and hierarchical control, how to activate interlocks, understand the actions that occur once interlocks are activated, and how to set and view trends. It’s important to note that this requires practice over time to master properly.
DCS is much simpler compared to PI diagrams, but it translates many of the tags found on PI diagrams into concrete values. With these data, it is possible to determine the conditions inside towers, tanks, and heat exchangers. There are also numerous alarm and interlock systems; when values exceed normal limits, a red indication is shown to signal that the values are too high. Further deviations can lead to accidents such as interlocks activating or safety valves opening. It’s best to memorize these data points over time