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PAControl.com http://www.pacontrol.com
Connecting You with Process Control Knowledge, Technologie and Experience.
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Process Control Fundamentals
Control in process industries refers to the regulation of all aspects of the process. Precise control of level, temperature, pressure and flow is important in many process applications. This tutorial introduces you to control in process industries, explains why control is important, and identifies different ways in which precise control is ensured.
The following five sections are included in this module:
* The importance of process control
* Control theory basics
* Components of control loops and ISA symbology
* Controller algorithms and tuning
* Process control systems
The pdf tutorial is 27MB big and therefore the download will take some time depending on your connection speed.
http://www.pacontrol.com/process-control-fundamentals.html
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PAControl.com Newsletter - April 2006
http://www.pacontrol.com
Connecting You with Process Control Knowledge, Technologie and Experience.
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1. Control Systems
2. Instrumentation
3. Fieldbus
4. OPC
5. Safety Instrumented Systems
6. Batch S88.01
7. Industrial Ethernet
8. Instrumentation and Engineering Jobs
9. Free Training/Tutorial Links
10. Message From An Advertiser
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1. Control Systems
Siemens Simatic PCS7
All system documentation for SIMATIC PCS 7 V 6.0 can be viewed and downloaded free.
The documentation is also available on an interactive CD-ROM – including a practical full text search through all manuals.
Compact expert knowledge:
The manuals for the various versions of SIMATIC PCS 7 offer detailed information and practical support.
From tips for beginners to detailed system and product documentation – all documentation literature for SIMATIC PCS 7 is available for viewing, downloading and ordering in up to five different languages.
https://pcs.khe.siemens.com/index.asp?Nr=5949#ein
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Visit related topics at http://www.pacontrol.com/Controller.html
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2. Instrumentation
Implementing Cold Junction Compensation in Thermocouple Applications
by Michelle Youn, Maxim Integrated Products
http://www.ecnmag.com/article/CA508469.html?ref=nbra
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Visit related topics at http://www.pacontrol.com/Instrument.html
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3. Fieldbus
Foundation Fieldbus Segment Design Tool
The Segment Design Tool is a Windows compatible program designed to provide a general guide for reducing the time required to engineer a FOUNDATION Fieldbus H1 segment. The Segment Design Tool checks the segment layout utilizing the FOUNDATION Fieldbus rules governing cable lengths, power consumption and proper segment termination.
http://www.emersonprocess.com/Systems/support/segment/
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Visit related topics at http://www.pacontrol.com/Fieldbus.html
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4. OPC Ole for Process Control
Free OPC servers Download
The tools which are listed on OPCconnect are all supplied free of charge, and are either pre-built or supplied as 'ready to build' source code, or both. Some are evaluation versions, and are identified as such.
They may all be downloaded from the Web http://www.opcconnect.com/freesrv.php
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Visit related topics at http://www.pacontrol.com/OPC.html
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5. Safety Instrumented Systems
Emerson's new SIS courses expand free online training at PlantWeb® University
As part of an ongoing effort to provide manufacturing professionals with relevant educational information on the latest technology developments, Emerson Process Management now offers courses on safety instrumented systems (SIS) at their PlantWeb® University online learning center. The new user-friendly courses provide fundamentals and practical tips for SIS planning, selection and implementation. The courses include concise information on basic SIS concepts, design and installation, operation and maintenance, safety standard compliance, and new "smart" SIS technologies.
http://plantweb.emersonprocess.com/university/default.asp
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Visit related topics at http://www.pacontrol.com/Safety.html
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6. Batch S88.01
Batch Control.com - Tutorials for the batch automation professional.
You can find on their website:
- An S88.01 tutorial
- An introduction to S95
- Ideas on how to sell S88 batch control to your management or customers
- Links to articles and other sites with batch control themes to aid in your learning and development
- A free PalmOS™ program so that S88 is never too far away
http://www.batchcontrol.com/index.shtml
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Visit related topics at http://www.pacontrol.com/Batch.html
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7. Industrial Ethernet
The online Industrial Ethernet Book
The Online Industrial Ethernet Book is a Directory and Information Source for Industrial Ethernet and Embedded Internet.
The publication is constantly broadening its coverage to include Ethernet TCP/IP applications, enterprise and internet connectivity, wireless networking and embedded networking and will continue to include the definitive directory of Industrial Ethernet products and services, supported by this rich and vibrant website devoted to the same market sectors.
http://ethernet.industrial-networking.com/
THE INDUSTRIAL WIRELESS BOOK
The Industrial Wireless Book promotes all types of wireless for industry including 802.11A, 802.11B, 802.11G, 802.15.4-based wireless mesh networking, WIFI, Bluetooth, GPRS, GSM and Lowpower radio. The Industrial Wireless Book recognised before most that wireless technology including wireless ethernet would be the next natural step for industrial automation.
http://wireless.industrial-networking.com/
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Visit related topics at http://www.pacontrol.com/Ethernet.html
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8. Instrumentation and Engineering Jobs
Instrumentation Engineer
http://www.thinkenergygroup.com/think.nsf/jobs1?openform&v=(dav)&cat=Instrumentation%20Engineer&Count=1000
Controls Engineering Jobs
http://www.thinkenergygroup.com/think.nsf/jobs1?openform&v=(dav)&cat=Controls%20Engineer&Count=1000
DCS Engineer
http://www.thinkjobs.com/think.nsf/jobs1?openform&v=(dav)&cat=DCS%20ENGINEER&Count=500
Process Engineering Jobs
http://www.thinkenergygroup.com/think.nsf/jobs1?openform&v=(dav)&cat=Process%20Engineer&Count=1000
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Visit related topics at http://www.pacontrol.com/EJobs.html
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9. Free Training/Tutorial Links and more
The ECOSSE Control HyperCourse: A refresher course for those involved in the development or use of control systems.
http://eweb.chemeng.ed.ac.uk/courses/control/restricted/course/index.html
Free AutoCAD Symbols and Blocks
ISA Symbol Library and more
http://www.cadresource.com/library/symbols.html
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PAControl.com Newsletter - December 2005
http://www.pacontrol.comConnecting You with Process Control Knowledge, Technologie and Experience.
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1. Control Systems
2. Instrumentation
3. Fieldbus
4. OPC
5. Safety Instrumented Systems
6. Batch S88.01
7. Industrial Ethernet
8. Instrumentation and Engineering Jobs
9. Free Training/Tutorial Links
10. Message From An Advertiser
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1. Control Systems
TURCK introduces BL67 Remote I/O Systems
The BL67 modular concept is a very flexible approach to connectorized I/O; the gateway, base, and electronic module combine many benefits. I/O modules are not dependent on the fieldbus protocol with the BL67 gateway. The gateway provides communication between the fieldbus and the I/O modules. The DIN-rail, or frame mountable base modules, are available with eurofast®, minifast® and picofast® connectors. The electronic modules are hot swappable. The power distribution module (24 VDC) supplies the connected I/O with the required voltage. The system supports multiple networks and a wide variety of I/O signals in a compact and rugged housing. The BL67’s strengths are its openness, flexibility, connectorization and ruggedness.
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Visit related topics at
http://www.pacontrol.com/Controller.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2. Instrumentation
Paperless recorders offer enhanced functions
The latest additions to the Yokogawa DaqStation family of paperless recorders are the S120 versions of the DX100 and DX200 units, which offer a number of enhanced functions and new capabilities. The DX Series is a family of advanced data-acquisition stations which combine the capabilities of intelligent paperless recorders with powerful communications and networking capabilities. The units feature easy-to-read colour TFT displays: a 5.5-inch display for the DX100 and a 10.4-inch display for the larger DX200.
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Visit related topics at
http://www.pacontrol.com/Instrument.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3. Fieldbus
A Fieldbus Design Tool
Designing a Fieldbus Network can be time-consuming!
That’s why Pepperl+Fuchs developed Segment Checker - a powerful software tool that reduces your design time.
Segment Checker is an open software tool that supports centralized and distributed fieldbus architecture concepts for both FOUNDATION Fieldbus and PROFIBUS PA.
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Visit related topics at
http://www.pacontrol.com/Fieldbus.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4. OPC Ole for Process Control
OPC Unified Architecture (UA for short) is the next generation of OPC.
First release specification and reference implementation are expected early in 2006.
OPC Foundation has developed UA in recognition of the following factors:
- Microsoft's COM and DCOM, the foundations of earlier OPC specifications, are now officially legacy technologies.
- Web services now offer the primary mechanism for data transport between computers (and also provide a better option for communications with plant-floor devices).
- Earlier OPC specifications failed to provide a single coherent data model - e.g. the Data Access item hierarchy was totally disjoint from that offered by Alarms & Events.
- Backwards compatibility with earlier OPC specifications is key to acceptance of any new standard.
Continue ...
http://www.opcconnect.com/ua.php~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Visit related topics at
http://www.pacontrol.com/OPC.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5. Safety Instrumented Systems
Safety Automation Equipment List
Available at no charge on the Internet, the Listing provides a compilation of all instrumentation equipment that has third party assessment for use in Safety Instrumented Systems applications.
The listing shows manufacturers, model numbers, assessment level and contact information.
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Visit related topics at
http://www.pacontrol.com/Safety.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
6. Batch S88.01
Batch processing is a common manufacturing method in the chemical, pharmaceutical, pulp and paper, and food and beverage industries. To find out more about the batch concepts used , start by pointing your Web browser to the World Batch Forum's (WBF) Web site at
www.wbf.org. The WBF is a nonprofit organization formed to promote understanding of batch process manufacturing concepts, methods, technologies, and standards, and to provide its membership a competitive edge in today's world market. It is an association of end users, vendors, consultants, and academics with a strict, noncommercial agenda. Each year, it hosts a conference with formal presentations and technical papers.
On its Web site, you will find, among other information, abstracts of papers presented at previously held conferences, a more detailed description of the WBF, news about happenings in the batch world, articles by members, and places to discuss batch-related topics with other professionals. You can also find out more about WBF sponsors and order WBF materials online.
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Visit related topics at
http://www.pacontrol.com/Batch.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7. Industrial Ethernet
Weidmuller Introduces Industrial Ethernet Overvoltage Protection Modules
A serious concern affecting industrial Ethernet networks is the electromagnetic, electrostatic and radio frequency interference generated by machines, power lines and other process control and automation devices that affect Ethernet data cables. These interferences can disturb electrical transmissions, and transients can damage Ethernet devices. Design Best Practices indicate that every active element in an industrial Ethernet network needs to be protected. It is not sufficient to just protect the AC/DC power inputs - the data ports also need protection.
Weidmuller’s Ethernet Overvoltage Protection Modules are designed to be used in between network nodes, and can be connected in series with the Ethernet switches, routers and media converters. Incorporated straight into Ethernet data cables in front of the devices, the OVP modules protect Ethernet ports against voltage and current surges. The OVP module features quick response suppression diodes that respond within a nanosecond of a surge detection to guarantee a high level of protection for signal lines. Surges are safely redirected via a ground connection and the interference voltage is limited to a safe level below 45V. Weidmuller’s Ethernet OVP modules can be used both inside and outside control panel cabinets that do not require an IP67 protection rating. They are available in versions for both DIN-rail and wall mounting.
In addition to Ethernet Overvoltage Protection Modules, Weidmuller also offers managed and unmanaged Ethernet switches, industrial routers, media and protocol converters, electrical cables (patch and network cables), and optical Ethernet cables, cable entry systems, connection modules, cable testers, Ethernet outlets, connection sockets, front plate interfaces, markers, RJ45 dust caps, couplers, plugs, installation flanges, Class 2 approved 24V DC power supplies, and installation and maintenance tools.
More about it
http://www.weidmuller.com/portal/page?_pageid=33,960013&_dad=portal&_schema=PORTAL~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Visit related topics at
http://www.pacontrol.com/Ethernet.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8. Instrumentation and Engineering Jobs
Jobsearchworld.com is a website for job search & career Promotion. You can find information and Job Listing.
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Visit related topics at
http://www.pacontrol.com/EJobs.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9. Free Training/Tutorial Links
Feedback and Temperature Control by Charles D.H. Williams
http://newton.ex.ac.uk/teaching/CDHW/Feedback/
Fuzzy Logic Tutorial
http://www.seattlerobotics.org/encoder/mar98/fuz/flindex.htmlTutorial for PID - Controlled Systems
http://www.shu.ac.uk/schools/eng/teaching/rw/pidtutorial.htmZIEGLER - NICHOLS PID TUNING
http://ourworld.compuserve.com/homepages/ACTGMBH/zn.htm
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10. Message from An Advertiser
Do you need an Automation Specialist with over 15 years experience?
Consulting, Engineering, Commissioning, Startup, ....
Visit
The Automation Expert~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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PAControl.com Newsflash - December,17 2005
http://www.pacontrol.comConnecting You with Process Control Knowledge, Technologie and Experience.
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Dear Newsletter Subscriber,
I've found some great links where you can download free software used for Process Control.
1.)
Windmill comDebug: serial communication software that lets you read data from instruments connected to your PC's COM port.
http://www.windmill.co.uk/serial.html2.)
All applications available from the next listed website are fully functional time-limited demos, and may be freely downloaded and distributed for evaluation purposes.
- Win32 Modbus Applications
- Modbus Simulation for Windows CE 3.00
- Modbus ActiveX Controls
- OPC Tools
- Listen Serial Data Monitor
- SocktSpy... WinSock Trace/Debug Utilities
http://www.win-tech.com/html/demos.htm~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Don't forget to visit us too. Go to
http://www.pacontrol.com~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3.)
Website with information on freely available OPC tools: clients for testing your servers, and servers for trying out your clients.
Free OPC Clients
Free OPC Servers
Free OPC Utilities
http://www.opcconnect.com/freestuf.php4.)
AUCOTEC - Free Demo Version ELCAD
Apart from the limitation of 8 circuit diagrams per project or 100 items per project, the range of features in Demo Mode in the fields of construction and list editing, is almost identical to the licensed version of ELCAD 7.
http://www.aucotec.com/PagEd-index-page_id-149.html 5.)
A powerful HMI HMI SCADA system that features full process visualization, data collection and management, and supervisory control, easy to use SCADA MMI HMI Windows 95/98/NT/XP software package, for visual machine and process control.
It provides process monitoring, visualization and control, data logging and graphic display, historical trending, alarming, recipe handling, data archiving, security, project documentation, spreadsheet support and much, much more in one complete package.
New improved version 6.5 of our SCADA software ready for free download.
http://www.midatek.dk/download.htm~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Don't forget to visit us too. Go to
http://www.pacontrol.com~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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PAControl.com Newsflash - November,24 2005
http://www.pacontrol.comConnecting You with Process Control Knowledge, Technologie and Experience.
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Siemens provides FREE online courses:
Basics of Electricity
Basics of Electrical Products
Basics of AC Drives
Basics of AC Motors
Basics of Control Components
Basics of DC Drives
Basics of Motor Control Centers
Basics of PLC's
Basics of Sensors
Basics of Busway
Basics of Load Centers
Basics of Panelboards
Basics of Power Monitoring
Basics of Safety Switches
Basics of Surge Protection
Go to
http://www.sea.siemens.com/step/default.html to begin with the courses
or download it in pdf format
http://www.sea.siemens.com/step/downloads.html~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
For related information, go to
http://www.pacontrol.com~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Please forward this message to your friends and/or colleagues if you think they can benefit from this information.
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PAControl.com Newsletter Special - October, 2005
http://www.pacontrol.comConnecting You with Process Control Knowledge, Technologie and Experience.
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We have updated our website with following topics
1. Free PLC Training / Tutorial -
http://www.pacontrol.com/plctraining.html2. Learn more about Electrical Equipment and Components -
http://electricalequipment.pacontrol.com/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
For related information, go to
http://www.pacontrol.com~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Please forward this message to your friends and/or colleagues
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PAControl.com Newsletter Special - September, 2005
http://www.pacontrol.comConnecting You with Process Control Knowledge, Technologie and Experience.
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PLC Or DCS: What is the difference?
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You must automate a process, but you can't decide between a DCS and a PLC. Are these systems really all that different? The answers depend on a slew of other questions.
Turn the clock back 10-15 years: The programmable logic controller (PLC) is king of machine control while the distributed control system (DCS) dominates process control. If you manufacture plastic widgets, you speak PLC. If you produce chemicals, you speak DCS.
Today, the two technologies share kingdoms as the functional lines between them continue to blur. We now use each where the other used to rule. However, PLCs still dominate high-speed machine control, and DCSs prevail in complex continuous processes.
The early DCS looked dramatically different from the early PLC. Initially, the DCS performed the control functions of the analog panel instruments it replaced, and its interface mimicked their panel displays. DCSs then gained sequence logic capabilities to control batch processes as well as continuous ones. DCSs performed hundreds of analog measurements and controlled dozens of analog outputs, using multi-variable Proportional Integral Derivative (PID) control. With the same 8-bit microprocessor technology that gave rise to the DCS, PLCs began replacing conventional relay/solid-state logic in machine control. PLCs dealt with contact input/output (I/O) and started/stopped motors by performing Boolean logic calculations.
The big change in DCS over the past 20 years is its move from proprietary hardware to the personal computer (PC) and standard LAN technologies. With each advance in PC power, DCSs have moved up in power. PCs gave us speedy, responsive, multi-media, windowed, operator-process interfaces (OPI). Relational databases and spreadsheet software enhance the ability of DCSs to store and manipulate data. Artificial intelligence (AI) technology gives us "smart" alarming. Today's DCS architecturally looks much like the DCS of 20 years ago, but tomorrow's DCS may control through networked "smart" devices-with no I/O hardware of its own.
Most DCSs offer redundant controllers, networks, and I/Os. Most give you "built-in" redundancy and diagnostic features, with no need for user-written logic.
DCSs allow centralized configuration from the operator or engineering console in the control room. You can change programming offline, and download without restarting the system for the change to be effective.
DCSs allow inter-controller communications. You can do data exchange in most DCS systems ad hoc (no need for predefined data point lists). You access data by tag name, regardless of hardware or location.
DCSs use multi-tasking operating systems, so you can download and run applications aside from the real-time control functions and still do fractional-second control. DCSs now come in "micro" systems, to price-compete with PLCs-but with full DCS features and capabilities.
The typical DCS has integrated diagnostics and standard display templates that automatically extend/update when your database changes. This database is central to the system-you don't have different databases sitting in the controllers.
DCSs have user-friendly configuration tools, including structured English, control block libraries, SFC (sequential function chart), and even RLL (relay ladder logic).
Most DCSs allow graphical configuration, provide online diagnostics, and are self-documenting. Most provide for user-defined control blocks or customized strategies. The controllers execute control strategies as independent tasks; thus, making changes to part of the control logic has no impact on the rest.
An important difference between DCSs and PLCs is how vendors market them. DCS vendors typically sell a complete, working, integrated, and tested system; offering full application implementation. They offer many services: training, installation, field service, and integration with your Information Technology (IT) systems. A DCS vendor provides a server with a relational database, a LAN with PCs for office automation, networking support and integration of third-party applications and systems. The DCS vendor tries to be your "one-stop shop." The PLC is more of a "do-it-yourself" device, which is sometimes simpler to execute.
Programmable Logic Controllers. When PLCs were solely replacements for hard-wired relays, they had only digital I/O, with no operator interface or communications. Simple operator interfaces appeared, then evolved into increasingly complex interfaces as PLCs worked with increasingly complex automation problems. We went from a panel of buttons and I/O-driven lamps to PLC full-color customized graphic displays that run on SCADA software over a network.
PLCs now have many DCS-like control functions (e.g., PID algorithms) and analog I/O. They've moved past their birthplace: the digital world (switch and binary sensor inputs and output contacts to run motors and trigger solenoids).
PLCs are fast: They run an input-compute-output cycle in milliseconds. On the other hand, DCSs offer fractional second (1/2 to 1/10) control cycles. However, some DCSs provide interrupt/event-triggered logic for high-speed applications.
PLCs are simple, rugged computers with minimal peripherals and simple OSs. While increasing reliability, PLC simplicity is not conducive to redundancy. Thus, fully redundant ("hot," automatic, bumpless) variations of PLCs, with their added hardware and software, sometimes suffer from a reduction in their reliability-a characteristic PLCs are famous for.
Data exchange typically requires you to preassign data registers and hard code their addresses into the logic. If you add registers or need to reassign data, you typically have to deal manually with the Domino Effect.
Typical PLC Relay Ladder Logic (RLL) languages include function blocks that can perform complex control and math functions (e.g., PID algorithms). Complex multi-loop control functions (e.g., cascade management and loop initialization) are not typical. For functions too messy to implement in RLL, most PLCs provide a function block that calls a user-written program (usually in BASIC or C).
PLCs typically operate as "state" machines: They read all inputs, execute through the logic, and then drive the outputs. The user-written logic is typically one big RLL program, which means you may have to take the whole PLC off-line to make a change of any size. You also run into database synchronization problems because of the separation of PLCs and the Man Machine Interface (MMI) software packages, as opposed to the central databases of DCSs.
A PLC will run in a stand-alone configuration. A DCS controller normally expects an operator interface and communications, so it can send alarms, messages, trend updates, and display updates.
Many PLC installations use interface software from third-party vendors for improved graphics and various levels of alarming, trending, and reporting. The PLC and MMI software normally interact by sitting on the network and using the register exchange mechanism to get data from and to the various PLCs. This type of communication presumes you have preassigned data registers and can fetch data on an absolute address basis. This can lead to data processing errors (e.g., from the wrong input) you won't encounter with the central database of a DCS.
Some PLCs use proprietary networks, and others can use LANs. Either way, the communication functions are the same-fetch and put registers. This can result in bottlenecking and timing problems if too many PCs try communicating with too many PLCs over a network.
A PLC may have a third-party package for operator interfaces, LAN interface to PCs and peripherals, PLC data highway or bus, redundant controllers with local and distributed I/O, local MMI and local programming capability. The PLC would have redundant media support, but not the redundant communication hardware or I/O bus hardware you'd find in a DCS. A PLC would have preprogrammed I/O cards for specific signal types and ranges.
Today, the decision between PLC and DCS often depends on business issues rather than technical features. Questions to consider are those involving:
The internal expertise to execute the project,
Level of support available from a vendor/integrator,
Long-term maintainability, and
Life-cycle costs.
PLCs and DCSs overlap in their features, but also have distinct strengths and weaknesses. When deciding between the two, know who will deliver and support your system, and how they will do it.
For related information, go to
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