What is the difference between DCS interlock and SIS interlock? Which one is more priority?
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What is the difference between DCS interlock and SIS interlock? Which one is more priority?
One is for control purposes, and the other is for safety reasons.
From a control perspective, it is definitely the DCS that frequently issues commands, such as adjusting the five key parameters. Many SIS systems are shut down in a sequential manner; under normal operating conditions, they remain active.
SIS is a hard interlock. The ones within DCS are soft interlocks. SIS belongs to the highest level of interlocks within a DCS interlock system.
You know a lot about pipelines, processes, and control, right?
It shows that I’m cut out for hard work; leaders need to understand party, government, labor union, and youth organization affairs...
Who from BECE is upstairs? I also worked at BECE~
SIS interlock takes precedence; the SIS and DCS interlocks are two separate systems. The SIS interlock is designed to be fail-safe, while the DCS is generally designed to be non-fail-safe. When a signal needs to be sent to both DCS and SIS, it is sent to SIS first.
There’s a bit of misdirection here. SIS must be designed to be fault-safe, but DCS is also designed to be as fault-safe as possible, though it isn’t required to be.