Operator Interface System

CAPE-SAFB Tltiligiatinn with Operator Interface System 

Interactive Knowledge Window - Provides information about the reasoning of the failure and provide the root cause of any failure occurring, or simulated by operator, using HEM module 

Dynamic P ID display - Provides information about the faulty component to be displayed in the 

CAPE-SAFE Utilization with Plant Design Model 

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The designer or specifier of control panels and operator interface systems should consider the human factors (ergonomics) that affect the safe operation of the plant, such as ... 

In this section, more details about how the different components and modules within CAPE-SAFE will work within the integrated picture of PEEE. Case studies wiU be used from different plant types i.e. continuous and batch plants, as well as oil refinery process to show the mechanism of CAPE-SAFE following some scenarios. Other scenarios will be illustrated for the integration with some components within PEEE such as fault detection system, RCM-based CMMS, and operator interface system. 

Figure 9-13 shows a proposed operator interface system (OIS). Such operator interface system helps operator to carry out the daily work by providing information about the plant design and operation. CAPE-SAFE is integrated with the proposed OIS to provide and manipulate safety related data. This is done as per table 9-3. 

Sides of the implementation of the proposed integrated safety solution have been explained to show how the solution may work in the real plants. This has been shown in the integration with RCM-based CMMS, operation interface system, and the Fault detection system (using tele-robotics technologies). 

Gabbar, H.A. (2001a), Shimada, Y., Suzuki, K. Operator Interface System Using Plant Object-Oriented Model, Journal of Systems Engineering, Vol. 4, No. 3, 2001. 

Although digital control technology was first apphed to process control in 1959, the total dependence of the early centralized architectures on a single computer for all control and operator interface functions resulted in complex systems with dubious rehability. Adding a second processor increased both the complexity and the cost. Consequently, many installations provided analog backup systems to protect against a computer malfunction. 

Host computers. These are the most powerful computers in the system, capable of performing func tions not normally available in other units. They act as the arbitrator unit to route internodal communications. An operator interface is supported and various peripheral devices are coordinated. Computationally intensive tasks, such as optimization or advanced control strategies, are processed here. 

Initially, the microprocessor-based single-loop controllers made the power of digital control affordable to those with small processes. To compete with these products in small applications, the DCS suppliers have introduced micro-DCS versions of their products. As a PC-based operator interface is usually a component of the micro-DCS, there is sometimes little distinction between a micro-DCS and a system consisting of single-loop controllers coupled to a PC-based operator interface. 

Distributed Control System (DCS) A system that divides process control functions into specific areas interconnected by communications (normally data highways) to form a single entity. It is characterized by digital controllers, typically administered by central operation interfaces and intermittent scanning of the data highway. 

Humans require time to react to process alarms and control requirements. Reaction time must always be considered early in the plant design. It is inherently safer to decide early in process design what administrative controls the operator will be assigned to activate for safety control. Requiring periodic operator interface to the process system relieves boredom and heightens interest in knowing the current condition of the process. See Sections 6.4 and 6.5. 

A risk assessment analyses systems at two levels. The first level defines the functions the system must perform to respond successfully to an accident. The second level identifies the hardware for the systems use. The hardware identification (in the top event statement) describes minimum system operability and system boundaries (interfaces). Experience shows that the interfaces between a frontline system and its support systems are important to the system cs aluaiion and require a formal search to document the interactions. Such is facilitated by a failure modes and effect analysis (FMEA). Table S.4.4-2 is an example of an interaction FMEA for the interlace and support requirements for system operation. 

One of the significant drawbacks of multidimensional analytical methods is the specificity of the conditions of each separation mode for a particular sample type, together with restrictive requirements for the type and operational conditions of the interface between them. Therefore, extensive work in the method development stage, along with the availability of highly skilled personnel for operating such systems, are required. 

Products in Group 3 seem to us to represent the future of practical batch process control. In such systems, modern workstations perform the single-user functions (e.g control system design, set-up, and maintenance operator interface data collection historical reporting) for which they were designed, while powerful multitasking controllers perform actual control. As computer hardware and software standards continue to evolve toward distributed networks of processors optimized for specific kinds of tasks, such systems will, we feel, proliferate rapidly. 

Introduction The chemical processing industry relies on many types of instrumented systems, e.g., the basic process control systems (BPCSs) and safety instrumented system (SIS). The BPCS controls the process on a continuous basis to maintain it within prescribed control limits. Operators supervise the process and, when necessary, take action on the process through the BPCS or other independent operator interface. The SIS detects the existence of unacceptable process conditions and takes action on the process to bring it to a safe state. In the past, these systems have also been called emergency shutdown systems, safety interlock systems, and safety critical systems. 

Validation of the SIS functionality is performed as part of a site acceptance test (SAT). Validation involves a full functional test that demonstrates the SIS actually works in the real-world installation. It proves the SIS devices execute the logic according to the specification and ensures that the SIS and its devices interact as intended with other systems, such as the BPCS and operator interface. From a systematic error standpoint, the SAT also provides an opportunity for a first-pass validation of the procedures developed for the operating basis (see next subsection). 

Because these systems can monitor multiple processes, equipment, and infrastructure and then provide quick notification of, or response to, problems or upsets, SCADA systems typically provide the first line of detection for atypical or abnormal conditions. For example, a SCADA system that is connected to sensors that measure specific water quality parameters shows measurements outside of a specific range. A real-time customized operator interface screen could display and control critical systems monitoring parameters. 

The whole system, with its internal and external interfaces, is designed so that it can be adapted to the needs of any particular analytical wet-chemistry laboratory, and so that responsibility for the analysis can be assigned to the operator. The system can be arranged... 

MS Carey, "Safety Management of Process Faults A Position Paper on Human Factors Approaches for the Design of Operator Interfaces to Computer Based Control Systems", HSE Contract Research Report No 60/1993, HSE Books, 1993... 

Since the launch of the first commercial quadrupole ICP-MS instrument in 1983, the technology has evolved from large, floor-standing, manually operated systems, with limited functionality and relatively poor detection limit capabilities, to compact, sensitive and highly automated routine analytical instruments. In principle, all ICP-MS systems consist of similar components a sample introduction system, the ICP ion source, an interface system, the mass analyser, the detector and a vacuum system [8,11]. 

Operator interface with system is via a two position operator s console. Each operator has two working color CRTs and a custom keyboard. A fifth single CRT dedicated to alarm displays is shared by both operator positions. Additional equipment includes multi-pen chart recorders, alarm logger and report typer. The operator monitors operations via continuously updated custom graphic displays, status and alarm reports on the CRTs and can call up displays and execute control commands by using special function push buttons in the keyboard. 

The system interfaces i.e., the operator interface and interfaces to other systems and equipment... 

The order of testing should be considered to ensure retesting is minimized. Operator interface and screen displays are best tested before the system is used for other tests. Input/outputs need to be satisfactorily tested before other tests that are dependent on proven I/O signals, and trend display testing may be needed to support loop testing. For interfaces to other computer systems the main consideration is which system controls the access, selection, transfer, and use of validated data. 

System access security Diagnostic checks Operator interfaces Software installation verification Software backup and restoration Control and monitoring loop operation Alarm, event, and message handling Safety and operational interlocks... 

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