Solenoids Valve Interlock Questio
Solenoids Valve Interlock Questio
(OP)
I have a solenoids valve actuated diagram which I don't quite understand( pls see the attached test 1 and test 2pdf)
The first type solenoid valve have two limit switch HZSC and HZSO which seems to be used as permissives initiators in the DCS interlock.
But, I don't know how to decide it is position switch or open/close limit switch.
The second type solenod valve have XZSC and XZSO limit switch which seems to be used as permissives initiators in a safety interlock.
And, it seems have two soft link commands from the DCS used as reset and open/close swtich.
But, I don't know what is the difference of the two type valve.
And, ome more question is that do I have to count these HZSC, XZSC as an input signal and put on the cause part on the cause & effect table.
Could any master in I&C and process engineering field explain detail to me?
Thank you very much.
The first type solenoid valve have two limit switch HZSC and HZSO which seems to be used as permissives initiators in the DCS interlock.
But, I don't know how to decide it is position switch or open/close limit switch.
The second type solenod valve have XZSC and XZSO limit switch which seems to be used as permissives initiators in a safety interlock.
And, it seems have two soft link commands from the DCS used as reset and open/close swtich.
But, I don't know what is the difference of the two type valve.
And, ome more question is that do I have to count these HZSC, XZSC as an input signal and put on the cause part on the cause & effect table.
Could any master in I&C and process engineering field explain detail to me?
Thank you very much.





RE: Solenoids Valve Interlock Questio
The position switches appear to be DCS inputs for display only, one digital input each.
Two DCS outputs are shown. XY-B is a manual operator selection to open or close the valve from a DCS screen selection. Turn the output off to close the XV. XY-A is an interlock to a shutdown system. Once the trip is clear the DCS sends a signal to reset the shutdown logic.
Or perhpas not.
RE: Solenoids Valve Interlock Questio