What do the symbols in a PID flowchart mean?
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What do the symbols in a PID flowchart mean?
What does that 1/2 in the diagram represent?
I’m not sure if the status selection for the two three-way solenoid valves is correct!
Find a comparison table; it’s usually on the first page of the drawing
That isn’t 1/2; the letter “I” is on it, indicating interlocking. Take a look at the functional indicators and graphic symbols for process measurement and control instruments in HG/T 20505-2014
CAD drawings usually include a diagram that explains the meaning of various symbols; for example, PG refers to an on-site pressure gauge, XV refers to a pneumatic valve, PT refers to a remote pressure gauge, and FT refers to a remote flow meter, among others
The legend: PG refers to the on-site pressure gauge, XV refers to the pneumatic valve, PT refers to the remote pressure gauge, FT refers to the remote flow meter, etc
Is there any information regarding the instrument numbers?
The upper part is I, which stands for interlock, while the 2 below is the interlock number; it means that these solenoid valves are controlled by Interlock No. 2