Can DCS take signals from SIS and then adjust control valves (not on-off valves)?
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Can DCS take signals from SIS and then adjust control valves (not on-off valves)? If possible, compared to using a two-part safety barrier, which one has lower costs?
Use SIS’s AI points to form a loop with DCS’s AO?
Communication between the two types of systems, SIS and DCS, allows the output of 20 SIS units to be used as input for the DCS. I recommend using hard-wired connections, as they are more reliable; while soft-wired communication is possible, it is not trustworthy.
There’s a problem with your approach. SIS allows you to retrieve values, but it doesn’t permit you to manipulate them using other systems. If you make such changes, you will be held responsible, so be careful
It mainly depends on your SIL level; SIL3 does not allow this at all.
I also think there’s a problem with this. SIS is an independent instrument system whose role is safety control. The signal from the field entering the SIS should have corresponding interlock functions. If both interlocking and control are required, then the two functions must be carried out separately; however, if the SIS retrieves signals and then uses communication to send them to the DCS for control, this cannot be considered independent operation, and it is not allowed
It is entirely possible to retrieve signals from the SIS to control valves operated by the DCS, but does the specification permit this?
This post was last edited by Watercolor Field on 2019-6-14 at 15:45. You can’t mess with your sister-in-law when you get married, do you understand?