How is pneumatic valve interlock represented?
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This post was last edited by lp3484 on 2021-12-14 at 13:55. How should it be represented in the process flow diagram (PID) if two pneumatic valves cannot be opened simultaneously? And how should it be shown when only one of five valves can be opened at a time?
The PID diagram does not show the detailed logical relationships.
Taking two valves as an example, the letter S marked next to each valve on the diagram indicates interlocking; a dashed arrow points to the other valve, with \"open\" or \"close\" indicated at the end of the dashed line. A chain matrix is then written to further illustrate this.
The interlock logic specifications are reflected in the cause-and-effect table; if anything needs to be noted regarding PID, it should be included as a remark.