Force/Release:
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Force: The SIS requires a change to a DCS parameter. Subsequent changes by process logic or the operator are prevented until it is “released”. Release: The SIS no longer requires the DCS parameter to be forced to a certain value or the controller to be forced to Local Override. Thus it is “released” to the operator or the DCS to make changes. Mandatory: SIS requires changes to DCS parameters. Blocks subsequent changes by process logic or operators until it is "unblocked". Lift: SIS no longer requires DCS parameters to be forced to a specific value or the controller to be forced to a local override. Therefore, it is "released" to the operator or DCS to make changes. This post was last edited by echommm on 2008-2-24 11:12 ]
I don’t know whether these two modes are judged by the system itself or controlled by humans? If the system makes the judgment, it needs to determine a lot of parameters.
Force: The SIS requires a change to a DCS parameter. Subsequent changes by process logic or the operator are prevented until it is “released”. Release: The SIS no longer requires the DCS parameter to be forced to a certain value or the controller to be forced to Local Override. Thus it is “released” to the operator or the DCS to make changes. Mandatory: SIS requires changes to DCS parameters. Subsequent changes to process logic or operators are prohibited until the command is lifted. Lift: SIS no longer forces DCS parameters to be at a specific value or forces the controller to be in local override. Therefore, it is up to the operator or DCS to make changes after the command is "disarmed".
thyclaire modified it well!
I would like to ask the poster whether sis is an emergency shutdown control system. We call it ESD control system here, emergency shutdown. From the context, we can see that sis has a higher priority control function than DCS. DCS is the abbreviation of distributed control system. DCS is the operating system that operators use to control equipment. If so Force: The SIS requires a change to a DCS parameter. Subsequent changes by process logic or the operator are prevented until it is “released”. Release: The SIS no longer requires the DCS parameter to be forced to a certain value or the controller to be forced to Local Override. Thus it is “released” to the operator or the DCS to make changes. Can be translated as: SIS requires changes to DCS parameters. Subsequent operational adjustments by system logic or operators will be prohibited until the SIS releases the command. When the SIS no longer requires the DCS parameters to be forced to a certain value or the controller is no longer required to force on-site override, the SIS is released and the operator can operate or the DCS itself can adjust. The priority of the control system is SIS, followed by DCS. This operating system was also developed for better protection of the device. If it is stopped, there are too many control valves on the device, and it would be too busy for people to adjust it. Only by setting up different priority levels, when the device encounters an emergency, commands with higher priority will be executed to better protect the device. It is recommended that the poster communicate more with the instrument personnel, they will give the poster more knowledge in this area.
There is a slight difference in the definition of SIS on the 5th floor. SIS also means Safety Instrumented System, which means safety instrumented system. DCS is a decentralized control system, yes.
It's almost the same, just using different names. The functionality is the same.
Explain: SIS Safety Instrumented System DCS Distributed Control System EDS Emergency Shutdown System EDP Emergency Pressure Relief System... The "Petrochemical Basic Engineering Design Regulations" have relevant instrument control content. If you are interested, please see the following website http://www.chemchina.com.cn/chempwas/images/070929/20071008_2.doc
SIS focuses more on the safety protection of the device, while ESD emphasizes emergency shutdown in dangerous conditions.
study* Well, we don’t have a SIS system here, only an ESD system. We mistakenly thought it was an ESD system, which means that the highest priority is the ESD system, followed by the SIS system, and finally the DCS system. The control system is more advanced and scientific than ours. It should be a better and safer control device. If there is a small problem and the operator is too busy or misoperates, the SIS system will first adjust and prevent the DCS from operating, which means that the operator cannot operate. After the working conditions stabilize, the DCS or the system's logic program will start to take effect. This is more convenient and faster. If it still cannot be adjusted, ESD will act and the device will stop. The process flow of this project of the poster is quite long. I personally feel that if so many control systems are designed, the process flow should be quite long. If there is a problem with the rear system, the SIS will perform load reduction and other operations on the front and rear systems, and the operator will perform operations after the system is stable. This can avoid misoperation by personnel. Advanced, really advanced.
For example, the French IFP PX device we use uses SIS and has more than 100 control valves, which is too complicated.
The moderator gave prestige +5 to this reply? Did I read that correctly? What are the criteria for increasing prestige? Guanyue often takes the trouble to explain it, but I haven’t seen it added yet? Looking forward to some explanation!
Wealth +5 and Charisma +1 are more reasonable. :P :P :P
It seems that echo understood it correctly and Buzhu has corrected it. I hope xyz will not be depressed by this. Don’t mind my bluntness. I look forward to your more participation: handshake