Experts, stop here....
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Dear colleagues in the instrumentation field, please take some time to explain the meaning of the codes on the drawings. Thank you
UZV valve, UZY solenoid valve, UZXO valve open signal, UZSC valve close signal, UZ13001 valve control signal, HZS130014 remote operation button
Since the legend is not visible, one can only rely on past experience; \"open/close\" indicates the on/off status of the valve as displayed in the SIS system. \"HZS\" refers to the SIS interlock signal, with the interlock condition being a high-high interlock. \"UZY\" is an electromagnetic valve, while \"UZV\" is the tag number for the shut-off valve
Thank you, expert. What is S/D? Connect to SIS or DCS?
Thank you, expert. I have another question: in S/D, CG COMP HZS, there is an ‘R’ in the lower right corner – what does each of these symbols mean?
HZS is the reset operation signal from DCS (Reset in the lower corner)
In this diagram, U denotes multi-function/multi-variable, while Z is a subsequent letter that, together with the first letter, indicates the variables/functions of the safety instrumented system; for example, UZ represents multi-variable/multi-function within the safety instrumented system functions, and HZ represents manual operation within those functions. What this diagram shows is that the manual reset function in the DCS (the circular box with a frame) sends a signal to UZ-13001 in the safety instrumented system (the diamond-shaped box with a frame), and then the open/closed status of the safety instrumented system valve UZV-130014 is displayed in the DCS.
It was explained very clearly; I’ve learned it, thank you