Communication between SIS and DCS systems, master-slave issue
Thread Content
I have a question: between the SIS system and the DCS system, which one is the primary and which one is the secondary? How can I tell the difference? ? What do master and slave mean? I don’t understand; could an expert please explain? Thank you
SIS and DCS are two separate systems; if there are connections between the interlock control points, it is recommended to use hard-wired connections for safety reasons. If it’s just some points for viewing purposes, communication can be used. As for which one is the slave and which one is the master, there seems to be no standard for that. I have many communication devices here, as well as a DCS master station
It doesn’t really matter whether DCS and SIS are the master or slave; in the case of DCS and field PLCs, generally the DCS acts as the master station while the PLC serves as the slave station. If unified management is the goal, it’s better to set up DCS as the master station.
In my work, DCS is used as the main station; the information from the SIS points is sent to DCS, and all the logical screens related to this are displayed on the DCS operation station
This post was last edited by 955559 on 2018-12-5 22:37. The master-slave concept comes from MODBUS. Because the MODBUS communication protocol is a master-slave protocol. The master station continuously polls the communication content from each slave station, while there is no communication between the slave stations. For the specific protocol, look for the MODBUS protocol online. PROFIBUS-DP is also a master-slave protocol.
Here, DCS is usually used as the master station, while SIS and PLC serve as slave stations. In a one-on-one situation, it doesn’t matter who takes the lead and who follows; as long as things are coordinated well for ease of operation, that’s fine. In a one-to-many scenario, it’s best for the party that needs multiple instances to serve as the master server.
Of course, SIS is the primary system, but it is generally not allowed to share instruments with DCS
SIS should be a separate system independent of DCS
The safety supervision agency requires independence; then why do you need to handle communications? SIS demands hard control