Naval cargo handling systems have traditionally been designed as two independent systems:the hardware itself and theinformation systems that control *** lack of integration often posed *** operator might not discover ...
详细信息
Naval cargo handling systems have traditionally been designed as two independent systems:the hardware itself and theinformation systems that control *** lack of integration often posed *** operator might not discover that alimit switch needed repair until performing the tedious process of routine maintenance,or when the system failed to operate and anextensive troubleshooting procedure *** today's technology,however,that has all *** switches and *** maintenance devices,and programmable logic controllers are integrated via networks such as DeviceNet and Ethernet toform the new generation of cargo handling *** systems not only reduce workload and manning through more powerfultroubleshooting tools and semi-automation,but they also decrease system downtime and maintenance costs by being able to identifymaintenance concerns before they cause a *** of the integrated networks installed on vertical package conveyors aspart of the Smart Carrier Program will illustrate how new technology and integrated networks are currently being applied to Navalcargo handling systems and how they might be used to further reduce shipboard workload,manning,and maintenance costs in theyears to come.
This paper discusses the object-oriented software design for an automatic blending system. By combining the advantages of a programmable logic controller (PLC) and an industrial control. PC (ICPC), an automatic blendi...
详细信息
This paper discusses the object-oriented software design for an automatic blending system. By combining the advantages of a programmable logic controller (PLC) and an industrial control. PC (ICPC), an automatic blending control system is developed for a chemical plant. The system structure and multithread-based communication approach are first presented in this paper. The overall software design issues, such as system requirements and functionalities, are then discussed in detail. Furthermore, by replacing the conventional dynamic link library (DLL) with virtual X device drivers (VxD's), a practical and cost-effective solution is provided to improve the robustness of the Windows platform-based automatic blending system in small- and medium-sized plants. (C) 2004 ISA-The Instrumentation, Systems and Automation Society.
A short history of canal automation is given. PLC-based canal automation is relatively new. Advances in PLC-based canal automation are listed. Also listed are some of the remaining challenges. Recent advances have bee...
详细信息
A short history of canal automation is given. PLC-based canal automation is relatively new. Advances in PLC-based canal automation are listed. Also listed are some of the remaining challenges. Recent advances have been made in understanding unsteady flow simulation procedures, the form of the control algorithms used, the tuning procedures for these control algorithms, and the field programming of the algorithms into PLCs. The experiences of the Cal Poly Irrigation Training and Research Center (ITRC) in automating a variety of canals with upstream and downstream control are given. Copyright (C) 2004 John Wiley Sons, Ltd.
This paper presents a design method to generate a ladder diagram (LD) automatically with the control Petri Net (CPN) for control of discrete event system. This method describes the specification of a practical system ...
详细信息
This paper presents a design method to generate a ladder diagram (LD) automatically with the control Petri Net (CPN) for control of discrete event system. This method describes the specification of a practical system with the CPN that associates operations with places and conditions with transitions. Based on the firing regulation of transition, the relationship of places, conditions, and events are formulated with Boolean functions. These functions can be easily converted into LD and implemented on a programmable logic controller (PLC). An application example in a liquid mixture system shows that the proposed method is effective and has the advantages of ease of understanding, modification, and maintenance.
To architecturally support the programming of safety related control applications in the graphical language Function Block Diagram and the verification of such software meeting the requirements of Safety Integrity Lev...
详细信息
To architecturally support the programming of safety related control applications in the graphical language Function Block Diagram and the verification of such software meeting the requirements of Safety Integrity Level SIL 3, a dedicated, low complexity execution platform is presented. Its hardware is fault detecting to immediately initiate emergency shut-downs in case of malfunctions. By design, there is no semantic gap between the programming and machine execution levels, enabling the safety licensing of application software by extremely simple, but rigorous methods, viz., diverse back translation and inspection. Operating in a strictly periodic fashion, the platform exhibits fully predictable real time behaviour.
In this paper project of the automation system for controlled cooling of the steel shapes 200 mm x 200 mm was described. Simulation of cooling process, principle of operation, arrangement of sensors, valves, algorithm...
详细信息
In this paper project of the automation system for controlled cooling of the steel shapes 200 mm x 200 mm was described. Simulation of cooling process, principle of operation, arrangement of sensors, valves, algorithm of functioning, time dependences and formulas describing using of the cooling medium were showed. (C) 2004 Elsevier B.V. All rights reserved.
This paper presents a kind of automatic arc suppression equipment with fast response based on thyristor switched capacitor (TSC) control technology. It can mitigate the bad effects caused by single-phase-to-ground-fau...
详细信息
ISBN:
(纸本)0780387309
This paper presents a kind of automatic arc suppression equipment with fast response based on thyristor switched capacitor (TSC) control technology. It can mitigate the bad effects caused by single-phase-to-ground-faults in the distribution system. Three functions were realized in order to ensure the equipment's safe and reliable operation: first, intelligent distinguishing a single-phase-to-ground-fault;second, accurate measure of the capacitive reactance of the system-to-ground;third, safe running of thyristors. The control system's hardware composed of PLC, HMI of touch screen and across-zero trigger boards is also proposed. The simulation tests prove the equipment has acceptable performance.
In this paper project of the automation system for controlled cooling of the steel shapes 200 mm x 200 mm was described. Simulation of cooling process, principle of operation, arrangement of sensors, valves, algorithm...
详细信息
In this paper project of the automation system for controlled cooling of the steel shapes 200 mm x 200 mm was described. Simulation of cooling process, principle of operation, arrangement of sensors, valves, algorithm of functioning, time dependences and formulas describing using of the cooling medium were showed. (C) 2004 Elsevier B.V. All rights reserved.
This work solves a problem of the inverted pendulum system regulation using a fuzzy regulator. As this regulator has been used the programmable logic controller (PLC) Tecomat TC600, type 607. The PLC is connected to t...
详细信息
This work solves a problem of the inverted pendulum system regulation using a fuzzy regulator. As this regulator has been used the programmable logic controller (PLC) Tecomat TC600, type 607. The PLC is connected to the personal computer (PC) by the use of a voltage converter and an industrial PC card PCI 1751. The PC works as a simulation device of the inverted pendulum system, where the simulation is performed by a program created in the Delphi programming language version 5. The fuzzy model used in the fuzzy regulator is designed directly for the inverted pendulum system. The whole application has been successfully tested and also very good results have been reached.
In many practical applications PLC engineers face the problem, that some essential hardware the PLC is supposed to operate, is not available during software development and commissioning, yet. Because of missing feedb...
详细信息
In many practical applications PLC engineers face the problem, that some essential hardware the PLC is supposed to operate, is not available during software development and commissioning, yet. Because of missing feedback signals from field, testing the control software can in such circumstances be very difficult, if ever possible. The purpose of the paper is to propose a certain method of programming, which enables the programmer to overcome the problem, at least partially. The key point of the method lies in replacing feedback signals generated by real hardware and sampled at PLC inputs, by signals generated inside the PLC by a special program block, performing software simulation.
暂无评论