Selection of the hydrogen extraction PSA control system
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Selection of the hydrogen extraction PSA control system； The DCS manufacturers contacted provided feedback that, as the control system for the entire plant, they are very reluctant to incorporate PSA control into the DCS, for reasons including a large number of points, difficulties in programming, and slow DCS response times ； He added that PLC program control is simpler and faster. As PSA manufacturers, we also oppose the use of a plant-wide DCS; we prefer that PSA systems have their own separate PLC or DCS ； Mainly because: proficient in programming, to earn more money, and it’s safe and reliable ； He added that CCR can also be introduced if controlled separately ； And it masks the attenuation of the PLC, saying that the DCS also has attenuation. What do the operators think? I don’t know. Please answer: I don’t know how most petrochemical companies make their choices. Please answer:
PSA systems are generally operated by independent PLCs, and are usually built directly by the PSA manufacturers
The interlock system can send him a stop signal; at our end, we have adjusted the operating coefficients in the DCS for this purpose
Please explain in detail whether this is the case: that is, signals from the PLC are sent to the DCS system, while the DCS can issue commands to the PLC and, in this way, change the operating parameters of the PLC in order to control the PSA? Is that the case? Another question: Where should the PSA’s PLC be placed, in the CCR? What is the limitation of PLC on signal transmission distance?
Our PSA DCS has a separate operation station, while the PSA PLC is located in a separate cabinet in the instrument room. Currently, our optical fibers run directly from the field to the central control room
Can the independent operation station of the PSA’s DCS control the PSA? It’s still just surveillance. Can your PSA be understood in this way: The PSA is mainly controlled by a PLC, with an operating station being set up separately for the PSA within the CCR?
Are you a user or a designer, or are you just curious?
My role should be that of a designer, but this task has always been outsourced to PSA’s specialized manufacturers. But I’m not sure about the advantages and disadvantages. What I want to know now is whether, with the PSA controlled by a PLC that in turn drives the DCS, it’s only the communication signals that are displayed, or whether it’s possible to control the PLC partially or entirely within the DCS in order to indirectly control the PSA? I need to find an excellent way to serve property owners.
PSA has an independent PLC; most of its operations are automated, while the DCS can be used for control