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STANDARD ORGANIZATIONS FOR SCADA SYSTEM GUIDE

STANDARD ORGANIZATIONS FOR SCADA SYSTEM GUIDE Organization body that standardized the use of SCADA system There are many organizations involved in the standardization of SCADA systems. This section details some of these organizations and the roles they play. The Institute of Electrical and Electronics Engineers (IEEE) The IEEE Standards Association (IEEE-SA) is a membership organization that produces Electrical and IT-Related standards that are used internationally. The IEEE has been involved in standardizing technologies for many years. The following standards have been published by the IEEE with respect to SCADA systems: • IEEE Std 999-1992 – IEEE Recommended Practice for Master/Remote Supervisory Control and Data Acquisition (SCADA) Communications. This recommended practice applies to the use of serial digital transmissions by supervisory control and data acquisition (SCADA) systems having geographically dispersed terminals. These types of systems typically utilize dedicated c

SCADA SYSTEM PROTOCOLS

SCADA SYSTEM PROTOCOLS What are the different protocols in using the SCADA system? In a SCADA system, the RTU accepts commands to operate control points, sets analog output levels, and responds to requests. It provides status, analog and accumulated data to the SCADA master station. The data representations sent are not identified in any fashion other than by unique addressing. The addressing is designed to correlate with the SCADA master station database. The RTU has no knowledge of which unique parameters it is monitoring in the real world. It simply monitors certain points and stores the information in a local addressing scheme. The SCADA master station is the part of the system that should “know” that the first status point of RTU number 27 is the status of a certain circuit breaker of a given substation. This represents the predominant SCADA systems and protocols in use in the utility industry today. Each protocol consists of two message sets or pairs. One set forms the maste

SCADA SYSTEM IMPLEMENTATION PROCEDURES

SCADA SYSTEM IMPLEMENTATION PROCEDURES What are the different ways in implementing the SCADA system? There are many different ways in which SCADA systems can be implemented. Before a SCADA or any other system is rolled out, you need to determine what function the system will perform. Depending on whether you are a utility company or a telecommunications provider, you have a number of options in creating your systems. There may be a need to employ different methods that are complimentary to each other. The way in which SCADA systems are connected can range from fiber optic cable to the use of satellite systems. The following sections will present some of the common ways in which SCADA systems are deployed. Twisted-Pair Metallic Cable Twisted-pair telecommunications cable is the most popular medium used by utilities and has existed in its present form for many years. The cables are essentially the same as those used by the Telephone Company and contain a number of pairs of conductor

SCADA ARCHITECTURES: NETWORKED SYSTEM

SCADA ARCHITECTURES: NETWORKED SYSTEM What is a SCADA third generation system known as networked system use for? SCADA systems have evolved in parallel with the growth and sophistication of modern computing technology. The following sections will provide a description of the following three generations of SCADA systems: • First Generation – Monolithic • Second Generation – Distributed • Third Generation – Networked Networked SCADA Systems The current generation of SCADA master station architecture is closely related to that of the second generation, with the primary difference being that of an open system architecture rather than a vendor controlled, proprietary environment. There are still multiple networked systems, sharing master station functions. There are still RTUs utilizing protocols that are vendor-proprietary. The major improvement in the third generation is that of opening the system architecture, utilizing open standards and protocols and making it possible to distri

SCADA ARCHITECTURES: DISTRIBUTED SYSTEM

SCADA ARCHITECTURES: DISTRIBUTED SYSTEM What is a SCADA second generation system known as distributed system use for? SCADA systems have evolved in parallel with the growth and sophistication of modern computing technology. The following sections will provide a description of the following three generations of SCADA systems: • First Generation – Monolithic • Second Generation – Distributed • Third Generation – Networked Distributed SCADA Systems The next generation of SCADA systems took advantage of developments and improvement in system miniaturization and Local Area Networking (LAN) technology to distribute the processing across multiple systems. Multiple stations, each with a specific function, were connected to a LAN and shared information with each other in real-time. These stations were typically of the mini-computer class, smaller and less expensive than their first generation processors. Some of these distributed stations served as communications processors, primarily c

SCADA ARCHITECTURES: MONOLITHIC SYSTEM

SCADA ARCHITECTURES: MONOLITHIC SYSTEM What is a SCADA first generation system known as Monolithic system use for? SCADA systems have evolved in parallel with the growth and sophistication of modern computing technology. The following sections will provide a description of the following three generations of SCADA systems: • First Generation – Monolithic • Second Generation – Distributed • Third Generation – Networked Monolithic SCADA Systems When SCADA systems were first developed, the concept of computing in general centered on “mainframe” systems. Networks were generally non-existent, and each centralized system stood alone. As a result, SCADA systems were standalone systems with virtually no connectivity to other systems. The Wide Area Networks (WANs) that were implemented to communicate with remote terminal units (RTUs) were designed with a single purpose in mind–that of communicating with RTUs in the field and nothing else. In addition, WAN protocols in use today were larg