PLC & Control

Daftar isi artikel yang berhubungan dengan PLC (Programmable Logic Controller) dan HMI (Human Machine Interface) atau MMI (Man Machine Interface) :

koneksi rslogix5000-rslinx-rsemu5000 dan intouch-rslinx-rsemu5000

coba-coba RSView SE ver.4.0

upgrade hmi tt2000 at xycom dos for solar turbine compressor

intouch 7.1-eagle-quantum for ww-rslinx-ab1784kt in WinNT-slc500 and eagle quantum

perbedaan bahasa pemrograman plc iec 61131-3

diskusi seputar design dan programming plc siemens s7-300

plc-programmable logic controller-part5

plc-programmable logic controller-part4

plc-programmable logic controller-part3

hmi or mmi-part3

wonderware intouch 10

hmi or mmi-part2

hubungan antara plc dan hmi/mmi

plc-programmable logic controller-part2

hmi or mmi-part1

seputar scada

plc-programmable logic controller

dcs vs plc

instr. control-tanya soal plc

Dalam sebuah artikel dikatakan bahwa PLC dan DCS mempunyai fungsi yang sama. Saat ini perbedaan DCS dan PLC telah kabur karena masing-masing telah saling mengambil peran. PLC mengambil sebagian peran DCS dan sebaliknya. Ini sangat berbeda dengan yang dipahami selama ini bahwa : - DCS (Distributed Control System) sesuai dengan namanya adalah sebuah SISTEM PENGONTROLAN yang bekerja menggunakan beberapa controller dan mengkoordinasikan kerja semua controller tersebut. Masing-masing controller tersebut menangani sebuah plant yang terpisah. Controller yang dimaksud tersebut adalah PLC. - Sedangkan PLC (Programmable Logic Controller) sesuai dengan namanya adalah sebuah CONTROLLER yang dapat deprogram kembali. Jika PLC hanya berdiri sendiri dan tidak digabungkan dengan PLC yang lain, SISTEM pengontrolannya dinamakan DDC. Jadi, PLC adalah sub sistem dari sebuah sistem besar yang bernama DCS. Yang sejajar dalam hal ini adalah DDC dengan DCS dan FF, serta PLC dengan SLC, Microcontroller, dan sebagainya. Benarkah demikian? Perkembangan awal PLC, difungsikan lebih ke logic Control (Discrete Input/Output). Tapi Sekarang, PLC sudah mengakomodasi bukan hanya discrete Input/Output, didalamnya sudah dapat menerima signal dari Thermocouple, RTD, Load Cell, dan sebagainya langsung ke I/O PLC. Mungkin ini yang menjadi “kabur”, dimana fungsi-fungsi tersebut sebelumnya dipegang oleh DCS, sekarang dengan PLC saja sudah bisa. PLC pada dasarnya hanya pengontrol logika yang dapat diprogram. Walaupun pada perkembangannya PLC sudah dilengkapi analog signal, kemampuan aritmatiknya sangat terbatas. Sedangkan DCS, Sistem Pengendali terdistribusi Penekanannya ada di D-nya, Distribusi, yaitu distribusi tiga hal : Distribusi Resiko kegagalan, Distribusi lokasi dan Distribusi Pengendalian dan Man Power. Secara tradisional, memang benar bahwa DCS lebih lambat responnya dibanding PLC. Karena memang untuk regulatory control tidak perlu respon yang terlalu cepat karena kalau gagal masih ada safety shutdown system. Satu (1) second overall masih cukup untuk hampir semua aplikasi. Berbeda dengan safety application yang sering merupakan ladang PLC. Sekarang, kelihatannya sudah berbeda karena hardware dari yang secara tradisional DCS vendor makin “seperti PLC”. Ada yang mengatakan, “PLC itu Install and Forget it”, kalau DCS kebalikannya, karena lebih bersifat kompleks dan perlu monitoring. Kalau dilihat dari kompleksitas sistemnya, tergantung bagaimana konfigurasi sistem yang dipasang. Shutdown System Plant dengan menggunakan PLC-based juga bisa sangat kompleks, jauh lebih kompleks dibanding dengan DCS. Kalau tidak, mengapa para ahli sedemikian peduli sampai mengeluarkan IEC-61508, IEC-61511, IEC-62601 dan sebagainya. PLC terbaru saat ini sudah sanggup untuk mengolah sejumlah besar informasi secara real time karena sudah memiliki RAM antara 2 - 6 MB, memiliki konektivitas dengan Ethernet dan dapat diprogram dalam bentuk teks terstruktur maupun ladder logic. Pun, umumnya dioperasikan dengan Windows XP, dilengkapi dengan Human Machine Interface, HMI (misalnya Rockwell RSView), yang memungkinkan diadopsinya aplikasi Visual Basic, Hysys dan aplikasi lainnya. Integrity level PLC tidak bisa dipandang secara individual, seharusnya dipadukan dengan final element dan sensor sebagai satu kesatuan Safety Instrumented Function (SIF). Perbedaan PLC dan DCS sekarang sudah tidak ada lagi, karena perkembangan teknologi yang sudah maju.. dimana PLC sudah banyak yang berperan sebagai DCS, malah lebih dari itu PLC bisa berperan seperti SAP…! PLC seringkali dipakai untuk safety system (trip system dari suatu equipment). Walaupun di DCS ada fasilitas LOGIC maupun sequence, kebanyakan untuk trip system, sinyal tripnya tetap diumpankan ke PLC, misalnya alarm LL dari level steam drum sinyalnya diumpankan ke PLC untuk men-TRIP-kan Boiler. Jadi perbedaan PLC ama DCS mungkin terletak pada kecepatan responnya. Dari studi kasus, di Caltex, DCS sudah lama dan ada penggantian dengan sistem PLC+MMI. Tapi biasanya, kalau di perusahaan migas ada dua sistem DCS dan PLC. PLC untuk Fire/gas and Shutdown System, DCS untuk Continuous Control. Juga banyak aplikasi yang lainnya, seperti spesifik kontrol untuk Compresor/turbin, Vibration Monitoring, Flow Computer System, Optimization,dan lain-lain. Dan semua apikasi itu bisa disambungkan ke DCS. DCS bisa memonitor semua sistem yang ada (PLC+MMI, flow computer, turbin control, optimization software, dan lain-lain). Mungkin sebenarnya bisa aja ditangani oleh satu DCS saja atau PLC+MMI saja. Tetapi di perusahaan Oil and Gas dibuat banyak sistem, salah satu alasannya untuk redundancy, kalau memakai satu sistem saja sekali mati, mati semua plantnya. Tetapi, kalau di industri makanan, mungkin cukup PLC+MMI saja, karena lebih murah daripada membeli DCS yang mahal. Pendapat lainnnya mengatakan bahwa PLC tidak sama dengan DCS, PLC bukan sub sistem DCS dan DCS bukan PLC yang dibesarkan. Bila dilihat dari awal terbentuknya kedua perangkat itu, PLC dibuat untuk menggantikan Relay Logic yang berfungsi sebagai shutdown system. DCS dibuat untuk menggantikan Controller (single Loop, multi loop, close loop, open loop, etc), yang mengendalikan jalannya Proses (Proses Control). Proses Controller tentu tidak sama dengan Logic Controller, dan jangan dipisahkan, karena akan berbeda maknanya. Dalam aplikasinyapun begitu. Maukah jika pada sistem pengaman (ESD/PLC) kita terjadi kegagalan, maka semua Control Process menjadi Uncontrol, karena PLC digunakan sebagai System Control..?? Atau sebaliknya, kita sudah tidak memiliki sistem pengaman (ESD/PLC), ketika Sistem Control terhadap proses (DCS) terjadi kegagalan, karena DCS juga digunakan sebagai ESD..???. Lebih jelas lagi jika kita melihat “kewajaran” peruntukannya kedua sistem tersebut. PLC “wajar/layak” digunakan untuk sistem pengaman (ESD) kompresor, pompa, turbin, heater, boiler, dan “Equipment Proses” yang lain. Sementara DCS, kewajaran peruntukannya adalah sistem “Pengendalian / Control”. Pengendalian terhadap perubahan level, flow, press, dan “Variable Proses” yang lain. Pada pengembangannya, PLC mulai menggunakan “Analog Input”. Input dari Transmitter atau Thermocouple. Tapi coba kita lihat ke Software pemrograman logic. Semua Analog input akan diubah menjadi Digital dan kembali menjadi parameter digital pada fungsi Logic yang digunakan. Kalaulah PLC kemudian memiliki fungsi PID Controller, lebih cenderung diperuntukan ke sistem dimana ESD dan proses control merupakan satu kesatuan Sequence yang tidak bisa dipisah. Misalnya Turbo Machinery Control. Tetapi kalau Aplikasi Anti surge, bukanlah ESD, dan lebih cenderung ke fungsi Control (bukan Logic). Bisa dilihat dari kasus sebagai berikut yang mungkin akan lebih terlihat dimana PLC dan DCS wajar diaplikasikan. Pada sebuah kompresor yang menggunakan sistem Auto Start untuk Pompa Lube Oil (L.O). Pompa yang normal beroperasi adalah Pompa Turbine (PT) dan Stand by adalah Pompa Motor (PM). Jika Press L.O. turun karena sesuatu hal misalnya PT Trip, setelah mencapai setting Press PM akan Auto Start. Penggunaan Sensor Press L.O. berupa Electronic Smart Pressure Transmitter dan Press.Trans. menjadi Analog input di PLC. Kejadiannya adalah : Saat PT Trip, PM terlambat Start dan kompresor Trip, karena turunnya press sangat cepat dibawah satu (1) detik. Setelah dilihat terjadi keterlambatan respon pada Press.transmitter, walaupun damping sudah minimum. Ternyata memang semua peralatan berbasis microprocessor itu akan memiliki Dead Time (juga dikatakan di Manual Book). Untuk mengatasinya kembali digunakan Pressure Switch untuk sistem Auto Start L.O. (sesuai desain awal). Apakah ada standard yang mengatakan sensor dari Sistem Logic ESD harus menggunakan Switch..??? Alangkah terlambat lagi jika input PLC berasal dari DCS. Dari cerita di atas, apakah kita akan menggukan DCS untuk fungsi PLC dan PLC untuk DCS..? Membicarakan mengenai beda antara PLC dan DCS selalu saja akan campur aduk kalau tidak di set dari awal kerangka berbicaranya pada tataran definisi atau realitas/kemampuan hardware software architecture-nya dalam mengerjakan tugas tertentu. Kalau berdasarkan definisinya, maka : PLC = Programmable Logic ControllerPLC secara definisi adalah sebuah controller (processor) yang bisa diprogram (programmable) yang fungsinya adalah menjalankan (execute) fungsi-fungsi logic. Logic yang dimaksud di sini, melihat pada sejarah awal dibuatnya, adalah discrete/sequence function yang biasanya ditangani oleh relay. Dari awalnya para vendor yang mengusung nama PLC memang bergerak di bisnis discrete/sequence control. DCS = Distributed Control SystemApapun system control yang terdistribusi (Sebagai lawan dari DDC = direct digital control) dikategorikan sebagai DCS. Pada DDC seluruh control dilakukan dalam central processor sehingga apabila dia kegagalan, seluruh control plant akan ikut gagal. DDC, digunakan hampir, kalau tidak bisa disebut keseluruhannya sebagai Regulatory Control. Dan dari awalnya vendor-vendor yang mengusung nama DCS memang menggunakan produknya sebagai regulatory control. Celakanya, para vendor yang ada pada masing-masing kubu ini mulai saling berebut pasar (terutama vendor yang dulunya mengaku vendor PLC). Ini disebabkan karena kemampuan processor/CPU dan juga memori yang makin cepat dan harganya juga makin murah. Mereka mulai “mengkhianati” dan mulailah ada cross application. Vendor yang dulunya mengusung nama PLC sudah mulai memasuki arena regulatory control karena mereka mulai pede dengan barang mereka. Demikian pula Vendor yang dulunya mengusung nama DCS mulai tertarik memasuki arena discrete karena dari segi hardware saat ini sudah memungkinkan processor-nya punya execution time yang cepat sehingga pasar dicrete sudah bisa dimasuki. Dengan begitu, kalau melihat pada menyataan kemampuan architecture barang yang dimiliki masing-masing, maka pengertian PLC dan DCS sudah mulai kabur. Maka kalau standard mengatakannya adalah “Programmable Electronic”. Anything programmable and its electronic based device. Khusus mengenai dikotomi switch dan transmitter, spesifikasi response transmitter yang response timenya (include dead time) adalah 100 ~ 500 miliseconds. Dead timenya sendiri 40 ~ 100 miliseconds. Standard tidak menyarankan mana yang lebih baik dipakai karena kedua-duanya sama baiknya tergantung aplikasinya (bahkan akibat kemampuan transmitter yang bisa dipakai untuk check trend data analog, maka pemakaian transmitter makin popular. Kalau terdapat masalah dengan transmitter jangan langsung ambil kesimpulan bahwa switch lebih baik daripada transmitter. Jangan-jangan transmitternya model kuno, atau salah pasang setting sehingga backup pump terlambat jalan. Untuk pompa berapa kecepatan respon pompanya sendiri yang notabene mechanical ??? Penentuan settingnya lebih krusial daripada mempermasalahkan switch atau transmitter. Dalam teori, controller sebuah safety control disarankan terpisah dari controller process control. Namun, hal ini bukanlah sebuah kemutlakan yang harus diikuti. Terkadang sebuah process control tidak bisa dipisahkan dengan safety control. Contoh : pada sebuah test station onshore, ESD adalah process control itu sendiri termasuk sistem alarmnya. Interlocking system yang berfungsi mengidentifikasi dan menindaklanjuti alarm-alarm kritikal semisal HHLL pada vessel juga adalah bagian dari process control. Artikel yang dimaksud di atas lebih tepat mengatakan bahwa “DCS dan PLC mempunyai banyak fungsionalitas yang sama”. Kalau dikatakan bahwa “DCS dan PLC mempunyai fungsi yang sama”, dapat diartikan bahwa seluruh functionality DCS dan PLC sama, padahal masih ada banyak fungsionalitas yang tidak sama antara DCS dan PLC. Perbedaan fungsionalitas tersebut juga berarti bahwa DCS dan PLC tidak bisa di implementasikan pada aplikasi yang sama. Misalnya untuk sebuah large chemical plant, tetap diperlukan kedua sistem DCS dan PLC, masing-masing untuk aplikasi sesuai dengan rancang bangun atau kegunaan dari sistem (DCS atau PLC).

• DCS bukanlah PLC yang besar. Kita bisa mempunyai DCS dengan 300 I/O dan 2 Processor Module, dan PLC dengan 8000 I/O dengan satu atau dua Processor Module; System Architecture DCS dan PLC berbeda.
• DCS juga bukan PLC-PLC yang terintegrasi menjadi satu system besar. Kata “Controller” pada PLC lebih ditujukan sebagai “Logic Controller”, sedangkan pada DCS lebih ditujukan sebagai “Process Controller”
• Baik DCS maupun PLC adalah configurable dan reconfigurable
• DDC dan PLC digabung ataupun tidak adalah dua system yang berbeda
• Kita tidak bisa menyejajarkan sistem yang berbeda-beda; sedangkan untuk sistem yang sama pun (sesama DCS atau sesama PLC) tidaklah mudah untuk menyejajarkan satu dengan yang lain. Tetapi memanglah demikian adanya. Topik ini adalah topik klasik yang sering dibicarakan dalam berbagai technical forum, tidak hanya di Indonesia tetapi juga secara internasional, dan tetap tidak membuahkan konklusi. Yang penting kita gunakan sistem yang sesuai dengan kegunaan.

Welcome to EasyDeltaV.com, your complete information source for Emerson Process Management's DeltaV digital automation system. To develop and maintain a competitive advantage, it's time to take your plant digital, with the first fully digital automation system, the DeltaV system. It's part of the PlantWeb architecture which delivers proven results across the globe. From a suite of digital busses, to embedded advanced control, to easy enterprise integration and optimization, the DeltaV system delivers precision control and predictive maintenance -- easy. Join the thousands of process manufacturers from industries including oil & gas, refining, chemicals, pharmaceuticals, biotechnology, pulp & paper, food & beverage, metals, mining & utilities who rely on the DeltaV system to improve the performance of their operations. If the DeltaV system is new for you, visit the About DeltaV section for a quick overview.

Yes, if you want an automation system for applications of any size. Since 1996, the DeltaV system has been commissioned in automation applications across the globe in projects ranging from 8 I/O up to 30,000 I/O. Industries like Life Sciences and Biotechs, Oil, Gas, & Hydrocarbons, Chemicals and Specialty Chemicals, Pulp & Paper, Food & Beverage, and Metals, Mining, & Minerals have increased the return on their automation investment with the DeltaV system. Yes, if you want to join others who have dramatically reduced their automation capital project costs and ongoing operations and maintenance costs with open, interoperable bus technologies like FOUNDATION fieldbus, AS-i bus, Profibus DP, and DeviceNet. Only the DeltaV system is "built for busses" and a key component of the proven PlantWeb architecture, which delivers revolutionary results. Yes, if you want to take advantage of predictive technologies to avoid unplanned shutdowns and eliminate mundane practices that chip away at profits. You can make the most of your intelligent HART and FOUNDATION fieldbus devices by using AMSinside DeltaV predictive maintenance software. Only the DeltaV system is built with AMSinside so all of the device diagnostics are right at your fingertips in the control room and the maintenance shop. Yes, if you want your automation system to easily integrate with your enterprise planning systems and personal communications devices like wireless phones, pagers, and PDAs. The DeltaV system incorporates open, interoperable standards like OLE for Process Control (OPC), XML, and ODBC. Yes, if you want to improve the performance of your plant with embedded advanced control applications, which can be applied by a typical process engineer, not an expert consultant. Reducing process variability, reducing switchover times between product runs, predicting upsets, and avoiding downtime are easily achieved when advanced control is embedded with traditional plant automation. Yes, if you need the most integrated batch capabilities available today, like all of the top 24 life sciences companies around the globe that are currently using DeltaV Batch, in one of the most highly regulated industries today. DeltaV Batch simplifies regulatory compliance with the FDA's 21 CFR Part 11, OSHA, and ISO 9000 by automating the change management process and reduces the time and energy required to meet these demands. Yes, if you want the peace of mind you get from controlling your plant with a system surpassing 6 sigma quality standards. The DeltaV system not only surpasses this level of quality from its introduction in 1996, it's controlling some of the most challenging processes around the globe, from oil and gas production on the frigid North Slope of Alaska, to refinery Cat Crackers in China, to sterile, clean life sciences processes. Yes, if you want to take advantage of SureService support services which lead the industry year after year as voted by the readers of Control magazine. DeltaV technology coupled with world-class SureService support helps you to reduce lifecycle costs and increase plant availability, efficiency and performance. We invite you to continue browsing our site. If this is your first introduction to the DeltaV system, a great place to start is the "Creating the Digital Plant" Supplement from the magazine. You can also dig into the product details using the Product Data Sheets and Whitepapers or learn how the DeltaV system has delivered results to users across all industries and world areas and how it can deliver results for you by studying the Success Stories and Video Case Studies.

MARKHAM, Ontario & PHOENIX & WESTBOROUGH, Mass.--(BUSINESS WIRE)--Enghouse Systems Limited (TSX: ESL) and Syntellect Inc. today announced the acquisition of the business and assets of Envox Group AB. The acquisition was completed for a purchase price of $14,000,000, subject to certain adjustments. Envox’s annual revenues are approximately US$16,000,000. With more than 40 years combined experience, Syntellect and Envox have a strong tradition of expertise and experience serving the Interactive Voice Response and Contact Center industries. The complementary product portfolios enable the delivery of truly open contact center solutions. “We are very pleased with the acquisition of Envox,” stated Stephen Sadler, chairman & CEO of Enghouse. “The acquisition of a well known industry leader like Envox will allow us to continue our global presence and expand to new territories in APAC and Europe.” Steve Dodenhoff, president of Syntellect, added, “Envox’s global reach, distribution channels, market focus and technology portfolio are a perfect complement to Syntellect’s core business. The combined organization, capabilities and product portfolio will be able to address the full spectrum of market opportunities in the contact center space. We are excited about this acquisition as it will accelerate our next generation Customer Interaction Management initiatives.” About Syntellect Inc. At Syntellect, we help our customers create, maintain and continuously improve superior end-to-end service for their customers - personalized service that values their preferences from the way they contact a business, to the level of help desired. We measure our success by our ability to implement and continuously support solutions for our customers. With two decades of pioneering leadership and thousands of solutions deployed globally, Syntellect is a premier provider of enterprise-class contact center solutions for the utilities, financial services, government, high-technology, help desk, consumer products, and healthcare industries. Syntellect is headquartered in Phoenix, Arizona, with additional offices in North America and the United Kingdom. For more information about Syntellect, Inc. visit www.syntellect.com About Enghouse Systems Limited Enghouse Systems Limited is a leading global provider of enterprise software solutions serving a variety of vertical markets. Its strategy is to build a large diverse enterprise software company through strategic acquisitions and managed growth. Enghouse shares are listed on the Toronto Stock Exchange under the symbol “ESL”. Further information about Enghouse may be obtained from its web site at www.enghouse.com. About Envox Worldwide Envox Worldwide is a leading global provider of IP-based voice self-service and contact center solutions. The company’s standards-based software solutions dramatically reduce customer service costs, optimize contact center performance, and improve customer satisfaction. More than 1.25 million ports of Envox’s hosted and premise-based IVR solutions have been deployed globally and over one million contact center agents benefit from the intelligent routing, screen pop and call monitoring functionality provided by Envox’s award-winning CTI software.

DeltaV is the creation of Emerson Process Management's technological innovators, who worked in an off-site "out-of-the-box" think tank to build an automation system that could integrate and leverage today's digital world and cutting-edge technological innovations to make a value step-change in the process industries. The name DeltaV is derived from the engineering equation for acceleration: dv/dt, the change in velocity over the change in time. The DeltaV system makes planning, engineering, installing, commissioning, training, operating, and maintaining your process EASY, which accelerates your success in improving your plant performance. The DeltaV system scales the complete range of applications from an isolated process area to a complete plant-wide automation system. Whether you need tens of I/O or tens of thousands of I/O-any size you want! The DeltaV system provides all the tools to manage your process easier than ever before. The complete family of controllers is available to power your most advanced control strategies. Full controller and power supply redundancy is available for your mission-critical applications. The controller and I/O sub-system is rated for Class I, Division 2 and Zone 2 environments to reduce your installation costs. DeltaV workstations are based on the latest Intel-based microprocessors running the Microsoft Windows XP /Windows 2003 operating system. A complete range of applications is provided to cover system configuration, operator interface, engineering, maintenance, and integration functions. The DeltaV control network—a high-speed Ethernet LAN—provides system communications and connects the various system nodes. The control network can be fully redundant. DeltaV remote services extend the operations, engineering, and diagnostic applications across your enterprise network. Unlike PLC/HMI solutions, the completely integrated DeltaV system features a single database that coordinates all configuration activities. System configuration is globally distributed in the run-time environment. Emerson - DeltaV

Experion is Honeywell's unified system for process, business, and asset management that helps industrial manufacturers increase their profitability and productivity. Experion takes customers well beyond Distributed Control System (DCS) functionality with an advanced automation platform solution and innovative application integration to improve business performance and peace of mind. And there's no need to worry about upgrading from TDC 2000®/TDC 3000® or TotalPlant® Solution (TPS). The unique, patent pending design of Series C combines sleek styling and function to provide process I/O with reduced footprint, easier installation and maintenance, and longer life. The Series C form factor benefits extend to multiple modules, such as the Series C C300 Controller, the Fieldbus Interface Module, the Control Firewall, and HART analog modules. The Control Execution Environment (CEE) is the common core software used in the various controllers supported by ExperionTM. This includes the C200 Process Controller, the C300 Process Controller, the Application Control Environment (ACE) and the C200 Simulation Environment (SIM-C200). The CEE provides an execution and scheduling environment where control strategies are configured from a rich set of standard and optional function blocks using a single builder tool, Control Builder. Function blocks are grouped and wired together in a container to perform a specific control function such as a valve control strategy. The Control Execution Environment (CEE) supports two types of containers: the Control Module in which continuous and discrete controls are combined; and an SCM, which is used for sequence control. Function blocks support the complete control application range, such as continuous, discrete and batch control.

Advant OCS (Open Control System) is an ABB solution for operators to improve their manufacturing productivity and achieve sustainable competitive advantages. In 1992, based on the success of the Master systems in the 80's, the Master system began its evolution to Advant OCS. This evolution introduced high capacity controllers and I/O with an improved redundancy scheme. Also included were modern UNIX workstations, and in 1996 S800 I/O was added providing modular flexible remote I/O. In 2000, Advant OCS with Master Software began its next step in the evolution process with the introduction of Industrial IT enabled products. ABB's commitment to protecting your investment continues with these enhancements by providing connectivity to our latest control offering. A versatile and complete range of process I/O systems within the Advant family enables optimal user configurations: S100I/O - A rack-based I/O system for AC400 controllers S600I/O - A rack-based I/O system for AC100 controllers S800I/O - A highly modularized and flexible I/O-system Numerous characteristics and functions facilitate and improve operation, monitoring, and reengineering of each process in a company. 800xA Operations (Process Portal) and the proven AdvaCommand for Unix solution (based on HP-UX) are available as an operator station for Advant OCS with Master Software. The intuitive operator software provides consistent access and interaction with data from multiple control and I/O to plant and enterprise information.

The DCS is a control system which collects the data from the field and decides what to do with them. Data from the field can either be stored for future reference, used for simple process control, use in conjunction with data from another part of the plant for advanced control strategies. What must be in the DCS for it to be able to do so much?

Operator Console

These are like the monitors of our computers. They provide us with the feedback of what they are doing in the plant as well as the command we issue to the control system. These are also the places where operators issue commands to the field instruments.

Engineering Station

These are stations for engineers to configure the system and also to implement control algorithms.

History Module

This is like the harddisk of our PCs. They store the configurations of the DCS as well as the configurations of all the points in the plant. They also store the graphic files that are shown in the console and in most systems these days they are able to store some plant operating data.

Data Historian

These are usually extra pieces of software that are dedicated to store process variables, set points and output values. They are usually of higher scanning rates than that available in the history module.

Control Modules

These are like the brains of the DCS. Specially customized blocks are found here. These are customized to do control functions like PID control, ratio control, simple arithmetic and dynamic compensation. These days, advanced control features can also be found in them.

I/O

These manage the input and output of the DCS. Input and output can be digital or analogues. Digital I/Os are those like on/off, start/stop signals. Most of the process measurements and controller outputs are considered analogue. These are the points where the field instruments are hard-wired to. All above mentioned elements are connected by using a network, nowadays very often used is Ethernet. The practical and technological boundaries between a Distributed Control System DCS, Programmable Logic Controller PLC and Personal Computer PC control are blurring. Systems traditionally associated with process control are being used in discrete applications. Likewise, traditionally discrete solutions are used increasingly in both batch and continuous process control. Today's control hardware are constructed from many of the same standard industry components such as Intel processors. Therefore the only real difference between control systems is at the software level.