This paper presents the design of an active surveillance system consisting of an intelligent-controller and two video cameras (one with a fixed wide field of view and the other with a narrow moveable field of view). T...
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This paper presents the design of an active surveillance system consisting of an intelligent-controller and two video cameras (one with a fixed wide field of view and the other with a narrow moveable field of view). The controller, which is implemented within a single Altera FLEX 10K device, combines the functions of image capture and display, motion detection, background image update and control of the moveable camera. Correct functionality of the controller chip has been verified by simulation.
The programming requirements of programmablelogiccontrollers (PLC) have always been many and various. They are used by people from all kinds of different fields. Programming methods are expected to be application-or...
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The programming requirements of programmablelogiccontrollers (PLC) have always been many and various. They are used by people from all kinds of different fields. Programming methods are expected to be application-oriented and geared towards control engineering. Infoteam Software demonstrates that the PLCopen portability level specification of instruction list (IL) enables even the portability of graphical languages like Ladder or FBD as well as the code generated from computer aided software engineering (CASE) tools. This gives a far higher importance to PLCopen portability level standard that is visible at first. It is the prerequisite for reusing software in control automation.
To ensure that the ultimate goal of a correct translation from source code to executable code, a formal semantics of the safe subset is required. IEC 113-3 provides formal syntax for ST and IL but only defines semanti...
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To ensure that the ultimate goal of a correct translation from source code to executable code, a formal semantics of the safe subset is required. IEC 113-3 provides formal syntax for ST and IL but only defines semantics by example. Work needs to be carried out on the production of validation suites for IEC 1131-3 safe language compilers. Although IEC 1131-3 compilers are smaller than Ada compilers, if the effort of validating compilers is too great, some form of language annotations need to defined to allow correctness demonstrations to be performed. However, even if safe subsets are not available, awareness of ill-defined language features can be used to develop coding standards which can be applied on software projects.
The proceedings contains 5 papers. Topics discussed include safety related systems, software for programmablelogiccontrollers, safety aspects in expert systems, neural networks and fuzzy logic, control and safety st...
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The proceedings contains 5 papers. Topics discussed include safety related systems, software for programmablelogiccontrollers, safety aspects in expert systems, neural networks and fuzzy logic, control and safety strategy in water industry.
A computer based simulation technique has been developed to aid the procurement and testing of programmablelogiccontrollers (PLC) and condition monitoring software for electro-pneumatic and electro-hydraulic systems...
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A computer based simulation technique has been developed to aid the procurement and testing of programmablelogiccontrollers (PLC) and condition monitoring software for electro-pneumatic and electro-hydraulic systems working in an industrial manufacturing environment. Condition monitoring, using measurable parameters such as pressure, flow rate and fluid quality, can provide a useful indication of the current running condition of such systems and a warning of possible mechanical failure. At relatively low cost, substantial improvements in the testing and development capability has been obtained.
The proceedings contains 6 papers on the application of advanced programmablelogiccontrollers (PLCs) with specific experiences from water treatment. Topics discussed include fully automated waterworks, chlorination ...
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The proceedings contains 6 papers on the application of advanced programmablelogiccontrollers (PLCs) with specific experiences from water treatment. Topics discussed include fully automated waterworks, chlorination control in large treatment works, PLC application as a cell controller using a communication network, sequential fluid power system condition monitoring using PLCs, and the use of PLCs to control rapid gravity filter operations.
The feasibility of automating the control and cleaning of rapid gravity filters in a clarification tank through the application of a suitable programmablelogic controller (PLC) based strategy is examined. Results obt...
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The feasibility of automating the control and cleaning of rapid gravity filters in a clarification tank through the application of a suitable programmablelogic controller (PLC) based strategy is examined. Results obtained via the simulator indicate that features such as fault detection and handling capabilities proved to be an added bonus aside from being a low cost solution, and could be easily integrated within a total control strategy.
Design and implementation of a low cost flexible production unit for assembly, inspection and other sequential tasks while maintaining an open system architecture is explained. All components of the cell are connected...
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Design and implementation of a low cost flexible production unit for assembly, inspection and other sequential tasks while maintaining an open system architecture is explained. All components of the cell are connected to the production unit controller, a PLC, via the installation bus Controller Area Network (CAN). The design is flexible to accept a number of sensors with different functionality such as pressure, temperature, bar-code readers etc. which may be connected to the bus individually or via an intelligent peripheral device.
This paper reviews the experiences of Bechtel Water Technology (formerly NWW Engineering), in the application of programmablelogiccontrollers to projects which were designed and constructed on behalf of a major wate...
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This paper reviews the experiences of Bechtel Water Technology (formerly NWW Engineering), in the application of programmablelogiccontrollers to projects which were designed and constructed on behalf of a major water & wastewater utility, NWW Ltd. The paper outlines how experience of industrial disputes followed by the introduction of EC Drinking Water Directives during the 1980's generated a requirement to build a substantial number of unmanned automated plants. This resulted in a substantial increase in the number and sophistication of process control solutions produced. It outlines the challenges encountered during the life cycle of these sophisticated solutions and continues by considering how, in addition to the control requirements other factors such as the investment regime, operational constraints, and manpower skill levels influence the design of PLC control systems and led to different solutions being proposed for the Water and Wastewater treatment plants. It identifies how by the use of dynamic modelling techniques the company has been able to focus the application of advanced technology only to the areas where it is specifically needed, thus allowing simpler control systems to be provided for the bulk of its treatment processes. The paper reviews the adoption of PLC systems with SCADA interfaces, in preference to DCS packages. Standardization on a single supplier for PLC systems is identified as an opportunity to reduce project costs by allowing the generation of standard control systems architectures and the production of standard portable software.
Since 1970, Lyonnaise des Eaux has developed a policy of automation at its water treatment plants. Originally based on solid logic modules, the technology used was upgraded and improved in the late seventies by the pr...
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Since 1970, Lyonnaise des Eaux has developed a policy of automation at its water treatment plants. Originally based on solid logic modules, the technology used was upgraded and improved in the late seventies by the progressive and extensive use of programmablelogical controllers (PLC). Since 2nd of May 1984, the potable water production of the western suburb of Paris (1 million inhabitants) has been fully automated (with around 100 PLCs), and unmanned after hours. Originally used for the simple logic problem (replacement of solid logic and relays), over the years, PLC has been progressively used for supervisory control and data acquisition (SCADA), for chemical treatment closed loop regulation and for more sophisticated hydraulic balance regulation of waterworks. Basic equipment of all process control and SCADA systems, PLCs are mainly used for real time process control and data collection when remote terminal units (RTU) are used for stamp dated data communication protocol and monitoring purposes on distribution networks. SCADA systems are now built as patchworks of various brands and types of equipment (when necessary). The long term nature of French water business contracts (average contract is 20 to 25 years) necessitates the use of a strategy which offers a good sustainable investment. By using industrial standards and not proprietary facilities (for communication protocol, databases, and local area network, or LAN), sustainability of the investment was ensured. The know how for the design, the implementation and the maintenance of this equipment, mastered within our company, is, for us, a key element of our long term strategy.
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