Level 1 contains the programmable logic controllers (PLCs) or remote terminal units (RTUs). Level 4 is the production scheduling level.Level 3 is the production control level, which does not directly control the process, but is concerned with monitoring production and targets.Level 2 contains the supervisory computers, which collate information from processor nodes on the system, and provide the operator control screens.Level 1 contains the industrialised input/output (I/O) modules, and their associated distributed electronic processors.Level 0 contains the field devices such as flow and temperature sensors, and final control elements, such as control valves.The accompanying diagram is a general model which shows functional manufacturing levels using computerised control. The key attribute of a SCADA system is its ability to perform a supervisory operation over a variety of other proprietary devices. Control operations įunctional levels of a manufacturing control operation It is one of the most commonly-used types of industrial control systems, in spite of concerns about SCADA systems being vulnerable to cyberwarfare/cyberterrorism attacks. They can control large-scale processes that can include multiple sites, and work over large distances as well as small distance. In practice, large SCADA systems have grown to become very similar to distributed control systems in function, while using multiple means of interfacing with the plant. The SCADA concept was developed to be a universal means of remote-access to a variety of local control modules, which could be from different manufacturers and allowing access through standard automation protocols. the real-time control logic or controller calculations, are performed by networked modules connected to the field sensors and actuators.
The operator interfaces which enable monitoring and the issuing of process commands, like controller set point changes, are handled through the SCADA computer system. 8 Communication infrastructure and methods.
0 kommentar(er)
