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Contents

 

Unit 1

Historical Development of Automation..................................... 4

Unit 2

What is Automation?................................................................ 10

Unit 3

Feedback Controls.................................................................... 16

Unit 4

Machine Tools........................................................................... 21

Unit 5

Machine Programming............................................................. 25

Unit 6

Programmable Automation..................................................... 30

Unit 7

Robotics..................................................................................... 36

Unit 8

Computer Networks in Manufacturing.................................. 42

Unit 9

Microprocessors for Fluid Properties..................................... 46

Unit 10

Additional Reading................................................................... 51

 

BIBLIOGRAPHY.............................................68


Unit 1

Historical Development of Automation

 

Pre-reading Task

 

Scan the text for answering the following questions:

 

1 What are the main periods of the historical development of automation?

 

2 When was the first personal computer introduced?

Text

The history of automation has been a long evolutionary process, consisting of the development and refinement of the basic building blocks and highlighted by periodic discoveries and inventions. The history can be divided into two periods: before 1945 and after 1945 (or the end of World War II).

Early Development

 

The earlier period is represented by the slow development of basic devices such as the wheel, pulley, lever, screw, and gear and their application in assemblies such as waterwheels, windmills, and steam engines. These assemblies provided power sources to operate machinery. The Watt steam engine introduced an important feature in the machine design: the flying-ball governor. The governor consisted of a ball on the end of a hinged lever that was attached to a rotating shaft and that controlled a throttle valve. As the rotating speed of the shaft increased, centrifugal force caused the ball to move outward, forcing the lever to reduce the valve opening and slowing the motor speed. The flying-ball governor stands as an important early example of feedback controlone of the building blocks of automation.

Another development of significant note in the history of automation was the Jacquard loom, invented around 1800. This was a machine for weaving cloth from yarn whose operation was determined by metal plates containing holes. The hole pattern in a given plate controlled the shuttle motions, which in turn controlled the weaving pattern of the cloth produced. Different hole patterns produced different cloth patterns. Thus the Jacquard loom was the forerunner of the programmable machine.

By the early 1800s, the basic building blocks of automation (power source, feedback control, and programmable machines) had been developed, although the components were rudimentary and they had not been adequately assembled into working systems. It took many refinements and inventions to set the stage for the modern automation age. The development of electric-power, a mathematical theory of servomechanisms, and mechanized machines for mass production (e.g., transfer lines) whose programs were fixed by their hardware configuration all had occurred by the end of World War II.

Modern Development

 

The modern era since 1945 has witnessed the development of a number of technologies that have contributed significantly to automation. These technologies include the digital computer, integrated circuits leading to microprocessors and other small electronic components, mass data storage techniques, new sensor technologies such as lasers, and new software for machine programming. Table dates many of the important milestones in the development of early and modern automation technology.

 

Table 1.1 Historical Developments and Milestones in

 

Automation

 

Date Development
Ancient times Wheel, lever, pulley, cutting implements; assemblies such 'as water-wheels, carts
Middle ages Windmill, mechanical clock
Watt's steam engine
Jacquard's loom
First player piano a programmable machine
Moving assembly line for the Ford Model T
Mechanized transfer line for machining automobile engine components in England
Harder coins the term automation
First electronic digital computer (EN1AC)
Numerical control (NC machine tool developed at MIT; credit for the NC concept is given to J. Parsons and F. Stulen
First industrial robot designed in the United States: patent issued in 1961 for "programmed article transfer," developed by G. Devol
Solid-state integrated circuit developed by J. Kilby of Texas Instruments. Inc.
First Unimate robot based on Devol's design installed to unload parts in a die-casting operation
Development automatically programmed tooling (APT), a programming language for NC machine tools
First flexible manufacturing system (FMS) installed at Ingersoll-Rand plant in the United States.
Microprocessor developed at Texas Instruments. Inc.
Computer language for programming industrial robots developed at Stanford Research Institute

Continuation of Table 1.1

The VAL language for robot programming, based on the 1973 development study introduced commercially by Unimation, Inc.
Personal computer using microprocessor introduced by Apple Computer
Memory chips with megabyte capacity developed

Post-Text Exercises

 

Exercise 1.1 Read and Translate the Text into Ukrainian

Exercise 1.2 Comprehension Check

Answer the following questions:

 

1 What were the basic devices of the earlier period?

2 When did the modern era of automation begin?

3 What technologies are connected with modern era of automation development?

4 How did the governor act?

5 What were the forerunners of microprocessors?

6 When did the first electronic digital computer appear?

 

 

Exercise 1.5 Learn to Write a Summary

Give a short summary of the text in writing.

 

Unit 2

What is Automation?

Pre-reading Task

 

Scan the text for answering the following questions:

 

1 Where is the automation technology applied?

2 What does the automated system require to perform its functions?

 

Text

Automation is a technology in which a process or procedure is accomplished by means of programmed instructions usually combined with automatic feedback control to ensure the proper execution of the instructions. Although automation can be used in a wide variety of application areas, the term is most closely associated with manufacturing. In fact, the origination of the term is attributed to Del Harder, an engineering manager at Ford Motor Company in 1946, who coined it to describe the use of automatic devices and controls in mechanized production lines. Automation technology is applied in manufacturing operations, in: automated guided vehicles, conveyors, other automated material handling systems; automated storage-retrieval systems; automatic assembly machines; computer numerical control; industrial robots; process control using computers or programmable logic controllers; transfer lines.

 

Post-Text Exercises

 

Unit 3

Feedback Controls

Pre-reading Task

 

Scan the text for answering the following questions.

1 Why are feedback controls widely used in automated systems?

2 What are five basic components of a feedback control system?

 

Text

Feedback controls are widely used in automated systems to ensure that the programmed commands have been properly executed. A feedback control system consists of five basic components (Figure 1.2); (1) input signal, (2) process, (3) output, (4) feedback sensing elements, and (5) controller and actuators. The input signal represents the desired value of the process output.

Figure 3.1 Diagram of a feedback control system.

The output is some variable that is being measured and compared with the input. The output value is a function of the process. Sensing elements close the loop between output and input. Finally, the controller and actuators compare the output with the desired input and make adjustments in the process to reduce the difference between them.

An important example of feedback control in manufacturing is a positioning system. A typical purpose of the positioning system in production operations is to move a work part to a desired location relative to a tool or work head. Examples of positioning systems include numerical control machine tools, spot welding robots, electronic component insertion machines, and coordinate measuring machines. In operation, a programmed instruction directs the positioning system to move the worktable to a certain location defined by coordinate values in an axis system (e.g., x and y values in a Cartesian coordinate system). For an x-y positioning table, two feedback control systems are required, one for each axis. A common actuator for each axis in such a system consists of a leadscrew driven by an electric motor; rotation of the leadscrew is converted into translation of the table. The controller receives the coordinate value as its input from the program and transmits a signal to the motor to drive the leadscrew. As the table moves closer to the desired location, the difference between actual position and input x -value is reduced. The actual position is sensed by a feedback sensor, commonly an optical encoder. In the ideal, the controller drives the motor until the actual table position is equal to the desired input position.

As the example of the positioning system indicates, the process input is determined by the control program in an automated system. The program consists of a sequence of steps, each step in turn being sent as an input to the controller and actuator of the system. As each step is executed, the next step is then transmitted. In this step-by-step manner, the program is executed.

Post-Text Exercises

Exercise 3.1 Read and Translate the Text into Ukrainian

Unit 4

Machine Tools

Pre-reading Task

 

Scan the text for the main idea, answer the following questions:

1 What do NC, CNC and EDM mean?

2 When did the first steam-engines appear?

 

Text

Machine tools are the machinery used to process metals and nonmetallic materials to get desired shapes or properties in manufacturing industries. Therefore, they constitute the core of manufacturing systems. The modern form of machine tools was first introduced during the industrial revolution in the 18th century with the birth of steam engines. Those steam engine-powered machine tools opened the era of automation along with the use of jigs and fixtures. Particularly, the continual development of new tool materials since the early 20th century has been the major driving force in advancing the technology of machine tools. More rigid and higher speed machine tools have been required to use fully the capability of new tool materials. It is not uncommon to see machining operations of cast iron with cutting speeds exceeding 3000 fpm in the automotive industry today.

The way of automation using machine tools changed significantly as the demands of market shifted from inflexible automation for mass production to flexible automation for batch production. The introduction of numerically controlled (NC) machine tools made it possible to perform a variety of jobs on a single machine. Since its inception, the use of NC machine tools has shown a rapid growth. Currently, more than 75% of the money spent to purchase new machine tools goes to computer numerically controlled (CNC) machine tools.

Accuracy of CNC machine tools has improved significantly. Accuracy better than 0.0002 to 0.0003 in. is commonly achieved on production CNC machining centers at present. This improved accuracy is attributed to construction of more rigid and precision mechanical components, use of computer controlled compensation of positional errors, and adoption of more advanced microprocessors to generate required trajectory commands. In modern CNC machining centers, many in-process sensors are used to feedback various operating conditions to the controllers. In some cases, machine controllers can make adjustments automatically to improve accuracy or performance.

Similar progress has been made in forming machine tools. For instance, precise control of a forming process is achieved by continuous monitoring of pressure or temperature and controlling the ram velocity to improve the properties of a part being formed. Various machine tools for nontraditional processes have also been developed. Electrodischarge machines (EDM) are used to erode the work material by discharging electric sparks between the tool and workpiece. Both spark voltage and feed must be controlled. Laser cutting machines can cut various difficult-to-cut materials by focusing high energy light beams onto a small area and thereby vaporizing the material.

In general, most machine tools require precise motion control with feedback of various sensor signals. Manufacturing processes are typically stochastic, time varying, or uncertain due to the variation of material property, temperature, and environmental conditions. Therefore, true automation of machine tools would require intelligent process condition monitoring, diagnostics, and intelligent control.

Post-Text Exercises

Unit 5

Machine Programming

Pre-reading Task

 

Scan the text for answering the following questions:

 

1 Machine programs operate the system without human intervention, do not they?

2 What two basic categories can automation production be classified into?

 

Text

The actions performed by an automated system are determined by a program of instructions. The program operates the system without human intervention, although the automated process or procedure may involve human interaction (e.g., an automated teller machine). The instructions contained in the program specify the details of each action that must be accomplished, the sequence in which the actions must be performed, and variations in the sequence that may be required depending on circumstances.

In the simplest automated systems, the machine actions comprise a well-defined work cycle that is repeated continuously with little or no deviation from cycle to cycle. Many mass production operations fall into this category; examples include automatic screw machine cycles, stamping press operations, plastic molding, and die casting. These processes date back many decades, and the equipment has traditionally been controlled by hardware components such as cams, electromechanical relays, and limit switches. In addition to controlling the equipment, these components and their arrangement served as the program of instructions that regulated the sequence of actions in the work cycle.

Although these devices are often quite adequate for the modest control action requirements of these programs, modern controllers are based on microcomputers. The program of instructions for computer-controlled production equipment has included a variety of media over the years, such as magnetic tape, diskettes, computer memory, and other modern storage technologies.

Computer control provides the opportunity for additional functions to be incorporated in the operation, beyond simply regulating the machine cycle. Some of the additional functions include improving and upgrading the control software, including the addition of control functions not foreseen during initial equipment design; safety monitoring; monitoring of process data such as equipment performance and product quality; diagnostic routines for maintenance and to expedite repairs when equipment breakdowns occur; and a convenient human-machine interface. Modern computer-controlled programmable machines also are capable of higher level functions, such as decision making and process optimization.

The decision-making capability of the system is included in the program in the form of instructions that execute different actions depending on conditions and circumstances. Less than one set of conditions, the system responds one way, but under a different set of conditions, it responds in another way.

Decision making also allows an automated system to cope with unanticipated events in the work cycle, such as a broken tool or a part not positioned correctly in a fixture or other malfunction in the process. Many decision-making situations rely on the ability of the system to use sensors to monitor the process and sense the environment. The sensors indicate the presence of the unexpected event, and the program commands the system to deal with the event in an appropriate manner. This type of decision-making capability is often called error detection and recovery.

Process optimization is another aspect of programming in the operation and control of a production process. Optimization is applicable in situations where there is (1) a well-defined economic performance criterion, such as product cost, production rate, or process yield, and (2) the relationships between the process variables and the performance criterion are known. In these cases, the control program is designed to make adjustments in the process variables that tend to drive the process toward an optimal state.

 

Post-Text Exercises

 

Unit 6

Programmable Automation

Pre-reading Task

 

Scan the text for answering the following questions:

 

1 Examples of programmable automation include numerically controlled machine tools, industrial robots, and programmable logic controllers, do not they?

2 For programmable automation, is the equipment designed in such a way that the sequence of production operations is controlled by a program or by a man?

 

Text

For programmable automation, the equipment is designed in such a way that the sequence of production operations is controlled by a program, i.e., a set of coded instructions that can be read and interpreted by the system. Thus the operation sequence can be readily changed to permit different product configurations to be produced on the same equipment. Some of the features that characterize programmable automation include high investment in general-purpose programmable equipment, lower production rates than fixed automation, flexibility to deal with changes in product configuration, and suited to low and/or medium production of similar products or parts (e.g., part families). Examples of programmable automation include numerically controlled machine tools, industrial robots, and programmable logic controllers.

Programmable production systems are often used to produce parts or products in batches. They are especially appropriate when repeat orders for batches of the same product are expected. To produce each batch of a new product, the system must be programmed with the set of machine instructions that correspond to that product. The physical setup of the equipment must also be changed: special fixtures must be attached to the machine, and the appropriate tools must be loaded. This changeover procedure can be time-consuming. As a result, the usual production cycle for a given batch includes (1) a period during which the setup and reprogramming is accomplished and (2) a period in which the batch is processed. The setup-reprogramming period constitutes nonproductive time of the automated system.

The economics of programmable automation require that as the setup-reprogramming time increases, the production batch size must be made larger so as to spread the cost of lost production time over a larger number of units. Conversely, if setup and reprogramming time can be reduced to zero, the batch size can be reduced to one. This is the theoretical basis for flexible automation, an extension of programmable automation. A flexible automated system is one that is capable of producing a variety of products (or parts) with minimal lost time for changeovers from one product to the next. The time to reprogram the system and alter the physical setup is minimal and results in virtually no lost production time. Consequently, the system is capable of producing various combinations and schedules of products in a continuous flow, rather than batch production with interruptions between batches. The features of flexible automation are (1) high investment for a custom-engineered system, (2) continuous production of mixtures of products, (3) ability to change product mix to accommodate changes in demand rates for the different products made, (4) medium production rates, and (5) flexibility to deal with product design variations.

Flexible automated production systems operate in practice by one or more of the following approaches: (1) using part family concepts, by which the parts made on the system are limited in variety; (2) reprogramming the system in advance and/or off-line, so that reprogramming does not interrupt production; (3) downloading existing programs to the system to produce previously made parts for which programs are already prepared; (4) using quick-change fixtures so that physical setup time is minimized; (5) using a family of fixtures that have been designed for a limited number of part styles; and (6) equipping the system with a large number of quick-change tools that include the variety of processing operations needed to produce the part family. For these approaches to be successful, the variation in the part styles produced on a flexible automated production system is usually more limited than a batch-type programmable automation system. Examples of flexible automation are the flexible manufacturing systems for performing machining operations that date back to the late 1960s.

 

Post-Text Exercises

Unit 7

Robotics

Pre-reading Task

 

Scan the text for the main idea and answer the following question:

What do abbreviation RIA, ISO, JIRA mean?

 

Text

Industrial robotics is the science of designing, building, and applying industrial robots.

Specifically, robot work should be optimized to (1) minimize the time per unit of work produced; (2) minimize the amount of effort and energy expanded by operators; (3) minimize the amount of waste, scrap, and rework; (4) maximize quality of work produced; and (5) maximize safety.

What are robots? In the late 1970s the Robotic Industries Association (RIA; formerly the Robot Institute of America) defined a robot as "a manipulator, designed to move material, parts, tools or specialized devices through variable programmed motions for the performance of a variety of tasks." Although this definition does not directly include pick-and-place arms as robots, teleoperators and remotely controlled devices are often referred to also as robots. The International Standards Organization (ISO) has a more lengthy definition of an industrial robot:

A machine formed by a mechanism including several degrees of freedom, often having the appearance of one or several arms ending in a wrist capable of holding a tool or a workpiece or an inspection device. In particular, its control unit must use a memorizing device and sometimes it can use sensing or adaptation appliances taking into account environment and circumstances. These multipurpose machines are generally designed to carry out a repetitive function and can be adapted to other functions.

The RIA and ISO definitions both stress the multifunctional and programmable capabilities and, therefore, exclude special-purpose "hard automation" tools and equipment typically found in high volume production. Also excluded are manual remote manipulators, which are extensions of human hands for use in, for example, sterile, hot, or radioactive environments.

In Japan, the Japanese Industrial Robot Association (JIRA) classifies industrial robots by the method of input information and the method of teaching:

 

1 Manual Manipulators. Manipulators directly activated by the operator.

2 Fixed-sequence Robot. Robot that once programmed for a given sequence of operations is not easily changed.

3 Variable-sequence Robot. Robot that can be programmed for a given sequence of operations and can easily be changed or reprogrammed.

4 Playback Robot. Robot that "memorizes" work sequences taught by a human being who physically leads the device through the intended work pattern; the robot can then create this sequence repetitively from memory.

5 Numerically Controlled (NC) Robot. Robot that operates from and is controlled by digital data, as in the form of punched tape, cards, or digital switches; operates like a NC machine.

6 Intelligent Robot. Robot that uses sensory perception to evaluate its environment and make decisions and proceeds to operate accordingly.

 

The scientists have defined three generations of robot systems.

The first-generation of robot systems was defined for the various robots with limited computer power. Their main intelligent functions include programming by showing a sequence of manipulation steps by a human operator using a teach box. Without any sensors, these robots f require a prearranged and relatively fixed factory environment and, therefore, have limited use

The second-generation of robot systems was enhanced by the addition of a computer processor. A major step in industrial robotics development was the integration of a computer with the industrial robot mechanism.

Third-generation robot systems incorporate multiple computer processors and multiple arms that can operate asynchronously to perform several functions. These robots can already exhibit intelligent behavior, including knowledge-based control and learning abilities.

The relatively short history of industrial robots, about 40 yr, has been full of ingenious innovations. It is anticipated that with the current explosion of AI research and development efforts the next 40 yr will be just as exciting.

 

Post-Text Exercises

 

Unit 8

Pre-reading Task

 

Answer the following questions:

 

1 What do you know about computers?

2 Its advantageous to use computers in manufacturing. Do you agree with it? If yes, give your supporting ideas.

 

Text

Numerically controlled machine tools, process control, materials tracking and handling, inspection and quality control, manufacturing resource management, and operations planning are all manufacturing systems activities that have been profoundly affected by the introduction of low cost computers and embedded controllers. The collection of these computer systems led to large-scale factory automation and computer-integrated manufacturing (CIM). As manufacturing systems components become more intelligent, the information exchange between such components must be computerized to avoid bottlenecks in the system. Information exchange among computerized systems naturally led to computer networks. A manufacturing computer network is a communication system that permits the various devices connected to the network to communicate with each other over distances from several feet to several miles. Computer communication in the factory is done by using local area networks (LANs). All the devices in a factory such as computers, CNC machines, robots, programmable controllers, data collection devices, process controllers, and vision systems are attached to the network.

Initially, computer networks were not developed for manufacturing systems but for communication among machines for scientific computing and, later, for the telecommunications industries. The diversity and variation in sophistication of computer systems found in manufacturing systems present computer networking with unique challenges in standardization and industry acceptance. Paradoxically, it is the computerization of manufacturing systems that brought about the largest improvements in manufacturing technologies, quality, and cost containment.

Almost all of the computers used in manufacturing systems are digital computers. The communication among these computers needs to take one or more lines of data (single line or a bus) and represent the two binary states of each line in some physical medium. There are many suitable physical media each with many ways to represent the binary states.

Computer networks may be more important for small manufacturing businesses than for industry giants. The small enterprises constitute an important portion of the national industry, generating about two-thirds of the gross national product (GNP). They lag behind larger corporations in implementing high technology tools. Furthermore, they are growing in number of employees and in their contribution to major manufacturers as suppliers. Thus high technology manufacturing tools especially designed for small enterprises is a significant area of need with many opportunities for improvement

 

Post-Text Exercises

Exercise 8.1 Read and Translate the Text into Ukrainian

 

Unit 9

Pre-reading Task

 

Skim and scan the text for answering the following questions:

 

1 What are the desirable characteristics of microprocessors for fluid properties?

2 What is the maximum pressure at which microprocessors were tested?

 

Text

A mixture of air and atomized gasoline is sprayed into the combustion cylinders of an automobile engine. With each new tank of gas, the composition, source, and processing history of the fuel can change, so the octane, density, and the so-called "stoichiometric demand" for Oxygen of the gasoline will almost certainly change as well. These changes alter the mixture of air and filel in the cylinders that will give the most efficient combus- j tion. If the engine could adjust itself to these changes in fuel properties each tune the fuel tank is refilled, the vehicle would get better mileage and engine exhaust would be cleaner.

A chemical plant must continuously monitor for fugitive emissions (that is, for the discharge of gases other than air into the environment). If properties of air such as density, thermal conductivity and specific heat can be monitored at all relevant pressures and temperatures, a fugitive emission of, say, propane or methane could be indicated on a monitor as a measurable deviation from those properties.

Gas hydrocarbon is leaking from a system of storage tanks, but the traditional leak detectors cannot distinguish natural gas from propane, from gasoline fumes. Tracking the leak, not to mention assessing the danger of the leaking gas, demands that workers be able to instantly determine the identity of the gas.

In all three of these applications and in many others, the incentives are keen to develop small, stable, rugged, long-lived, low-power and low-cost devices for measuring a diverse spectrum of fluid properties on-line. In chemical processing, combustion, billing, or simply in transporting fluids, one would like to monitor the quality of the fluid continuously to determine its effects on; the efficiency and safety of an operation and to assess its impacts . on the environment.

We have found that a great many fluid properties can be measured in situ and on-line to within accuracies of 1% with a silicon microsensor that is quite similar to existing, off-the-shelf devices. Indeed, for some properties of mixed fluids, the repeatability and consistency of the measurements made by our microsensors is higher than that of the best corresponding thermophysical data in the scientific literature, obtained with more traditional devices. Thus the ultimate accuracy of the microsensors is currently limited more by the uncertainties in independent estimates of the measured quantities than by signal-to-noise limitations of the sensors themselves.

Our design strategy is to collocate several sensing elements within the small confines of a single silicon microchip. We then interface those measurements with software built into connecting integrated circuits that can correlate the primary measurements with the output properties of interest. Because of the wide use of natural gases and of fuel oils, we have initially focused our efforts on calibrating and measuring the average properties of those fluids.

Sensing more than one property at a time enables calibrations to be made that dramatically improve the accuracy of the output values. For example, by simultaneously measuring ambient temperature, pressure, thermal conductivity, and specific heat of a fluid, it is possible to derive the value of such parameters as the heating value, density, viscosity, or octane number of gaseous or liquid fuels, or as the critical compression ratio, compressibility factor, or Wobbe number of gaseous fuels. The open structure of the microsensor design eliminates concerns about over pressure. Sensors have been tested successfully at pressures from vacuum to the maximum pressures readily available in the laboratory, near 200 bar (3,000 pounds per square inch).

 

Post-Text Exercises

 

Unit 10

Additional Reading

Text 1

Eiffel Tower North Pillar:

The Lift

Built by Schneider Creusot in 1965, the North pillar lift is similar as are its equivalents on the other pillars, to a funicular railway with an incline which varies between 54 and 78. In fact, contrary to traditional lifts, it does not move in an enclosed shaft along straight guides, but runs on standard rails. A double carriage is mounted on the undercarriage. Together these form a variable geometry mechanism whose seating is supported by hydraulic jacks, whatever the angle of the track. The lift is moved by a winch which in turn is activated by a 355 kW separate field excitation d.c. motor. Two 2.85 m diameter Koeps pulleys, coupled to the motor by a differential reduction gear, drive 4 cables by friction. The load of the double carriage plus half the maximum playload are balanced by a 43 T counterweight. This is mounted on a trolley with a 4 ratio block and pulley system, which runs on a parallel track.

The mechanism has 3 different brake systems:

security brakes : these are pneumatically controlled band brakes, mounted on each driving pulley; they are used for stopping on a fault,

operational brakes : on the fast shaft, at the motor output; they consist of 2 clamps, one of which is regulated to maintain a braking deceleration of 1 m/s2, while the second is an on-off brake, and used as a parking brake,

emergency brakes : on the undercarriage ; they are activated by an overspeed of > 3.5 m/s or by the cable snapping ; they are claws which lock in the rack rail; the stop is damped by 4 oil coated hydraulic jacks.

The lift serves the first and second levels of the Tower.

Objectives

Safety and availability, hence redundancy

Lifts standard

Solution

All equipment is duplicated, from the MV/LV transformer station through to the motor:

two 20 kV/600 V, 630 kVA power transformers,

two 380 V/220 V, 100 kVA control transformers,

two sets of H5/H7 harmonic filters,

two 1200 A variable speed drives,

two control PLCs working in redundant configuration,

all safety devices such as those to protect against overtravel, overspeed and slowdown control, etc., are also controlled by a hardwired logic sequence, in accordance with the Lift Standard.

Operating modes

Automatic: the machine is directly controlled by a lift operator in the carriage, who can only control the up/down and emergency stop controls. The speed is set at 2.8 m/s.

Manual: the machine is controlled from the control panel at ground level, using the same controls as above. The speed can be adjusted from 0 to 2.8 m/s using a potentiometer. This operating mode is used daily when the lift is first started up, performing a return journey to run in the mechanism.

In these two operating modes, the lift systematically and automatically stops at the first level.

Manual inspection: the machine is controlled from the control panel; the speed is limited to 0.7 m/s and is controlled manually. This is the maintenance, repair or test operating mode. It does not systematically stop at the first level. In these 3 operating modes, acceleration and deceleration is automatically controlled according to the speed.

Breakdown mode: this is only used in the event of the mains supply or the Eiffel Tower back-up supply failing, or if the driving motor fails. It enables the carriage to be brought back to a level by releasing and manually operating the service brakes.

Either of two redundant Rectivar 84 1200 A digital variable speed drives can control the motor. Either of the two TSX 87-40 PLCs can also generate the signal for either of the speed drives, depending on the selected operating mode and the carriage position / speed feedback. This data is provided by the 4 encoder / tachometer pairs on the motor and the driving or deflection pulleys, and by magnetic switches on the track.

Communication between the carriage and the ground is performed by 2 types of connection with the carriage, either by inductive loop or by carrier current (Satec system) on one of the supply phases. The 2 PLCs are linked by a dual Ethway network to which a supervision system, developed by Spie Automation, is connected. This enables images to be shown, faults to be displayed, data logging, assistance with control and trouble-shooting. A further connection to the Building Management system will relay this supervision data to the Central Safety Station.

 

 

Text 2

 

The Castelsarrasin centre

The centre is supplied with commercial propane via a rail link from Geogaz Lavera on the Fos Gulf, and from Butagaz in Pauillac, in the Gironde region. The trains consist of twelve 80 T tank wagons, of which 45 T is used. After weighing on a weighbridge the wagons are directed onto 4 tracks and to 6 unloading stations. A gas compressor transfers the propane from the tank wagons to two underground storage tanks each with a capacity of 2500 m3. It takes an average of two days to transfer the gas from a 12-wagon train. Three mixed stations are used to load tank wagons for transfer to other sites, if required.

There are three loading stations for the low capacity (19 T)tanker trucks and high capacity (39 T) trucks which enter the site after being weighed on a weighbridge. The propane is pumped into them using vertical centrifugal pumps, each with a continuous nominal flow rate of 100 m'/hr. The flow is regulated by a pressure valve which delivers the gas to the storage area. A turbine used with two dosing pumps adjusts the quantity of methanol added to the propane while the trucks are loaded. It takes 12 minutes to load a 19 T truck.

Site safety is subject to particularly stringent construction and operating regulations. The fire safety system, supplied by two reservoirs of water, each containing 1300 m3, is pressurized using two sets of motor-driven pumps each handling 600 m3/hr. A third set, the same as the two others, acts as a backup. Three staff operate the site during the day. Outside normal opening hours trucks are loaded using a "self-service" system controlled by the automation system and monitored by a safety officer.

Objectives

To meet customers' needs, especially in terms of extending the opening hours of the loading stations, it is essential to have a tool which meets the criterion of standby redundancy. It must provide:

safety of personnel,

availability of plant.

Solution

The hardware architecture which has been implemented is organized into a number of levels.

Acquisition of data by various sensors (volume, flow rate, pressure and weight measurement devices).

At a higher level, two TSX 107 PLCs, in redundant configuration, perform the sequential processing of this data, check that the unloading and loading, storage and filling procedures are strictly adhered to,

transmit weight data to the ISP-70 weight indicators, transmit commands to start the electrically-driven pump sets and control the valves. The processing functions of these PLCs are also used to generate the settings for the two Altivar 5 speed drives which control the dosing pumps. Three XBT-C terminals are used for the operator dialogue. This enables containers to be identified and the truck/driver database to be checked (driver number, codes and authorizations, characteristics and regular checks, etc). They display transaction authorizations, and direct drivers to their allocated loading stations.

Two PCs withMonitor 77 software control the plant, manage the trains and trucks, manage stock levels, and deal with any potential problems. One PC is active, and the other is passive. They are interchangeable. These supervisors communicate with the TSX PLCs via the Mapway network. Their real-time database checks the data entered on the XBT terminals, and the weighing procedures before and after every operation. Thus, loading of trucks is prohibited in the case of an unauthorized driver or if there is some inconsistency with the information on the database. When a transaction is accepted a bulk cargo document is printed out for the driver. If the tanker is overloaded the document is not printed.

In parallel with this, processing is performed on a server PC linked to the two Monitor 77 PCs via an IBM PC Token Ring data network. Reports are transmitted daily via a Transpac network to the company's head office, where the invoicing department is based.

 

Safety

Site safety is based on hardware and procedure redundancy. An approved fail-safe PLC and the process PLCs continuously check each other to ensure that sequences are running correctly. In addition, all emergency shutdowns, gas sensors, level and pressure safety devices (which, if exceeded, place the storage areas in safe mode and automatically trigger the fire safety systems) are double checked.

Text 3

The tunnel

In fact "the tunnel" consists of 2 single track rail tunnels, North and South, 7.60 metres in diameter, linked every 375 metres to a central service tunnel 4.80 metres in diameter. They are also directly linked between each other every 250 metres by branch tunnels designed to relieve air compression effects caused by train movement.

The entire project, 150 km of tunnel with a volume of more than 6 million cubic metres, requires a 21 kV electrical power supply for all auxiliaries, lighting, ventilation, cooling, fire safety precautions, etc. In normal operation, this electrical supply is shared between the HV stations at Coquelles, France and Folkestone, England, which are themselves connected to the EDF (Electricite de France) and SEEBOARD (South East Electricity Board) networks respectively. A single national network can however assure supply of the total installation in the event of failure of the other. In addition, in the unlikely event of simultaneous failure of both national networks, 2 standby generating installations, one located at Puits de Sangatte and the other at Shakespeare Cliff, can each supply half of the auxiliary 21 kV network.

Well-defined HV supply network reconfiguration sequences have been developed corresponding to all possible situations and include load shedding, opening of loops, starting and coupling of standby generator sets, etc.

As the EDF and SEEBOARD networks are not in phase, any possibility of parallel operation is totally excluded.

The Objective

The safety interlocking system must assure continuity of the 21 kV supply.

Its function is therefore to inhibit incorrect closing commands transmitted by the control system to the circuit breakers separating the two networks.

 

The Solution

 

The 21 kV interlocking system installed corresponds to an active redundancy model. It is designed to offer maximum availability using "Fail Operational" criterion, which means that a single failure does not result in stoppage of the installation and that tolerance to failures is pushed to a maximum wherever possible. The entire network is controlled by 5 stations each comprising twoTSX series 7 redundant programmable controllers linked by Uni-Telway. Each PLC receives data on the status of the circuit breakers - open, closed, racked in, racked out - and of the voltage controllers concerned with the interlocking system. In addition, each PLC receives data on the status of its own components, such as input/output boards, power supplies, etc., which enables it to carry out self-diagnostics.

Each PLC carries out acorrespondence check designed to detect anomalies between input data and output commands.

Each station carries out a consistency check designed to validate the I/O information of its 2 PLCs and to correct malfunction or failures if necessary.

Permission Matrix

 

Data is transmitted to the other stations through 2 fibre optic dual networks and is centralised in a "Master" station. This station, located in Folkestone main west sub-station, comprises 2TSX 87 PLCs. It develops a set of "permit to close" signals based on a permission matrix. The permits to close are immediately distributed within the "Master" station itself and to the other "Slave" stations, comprising TSX 47 PLCs, to update their outputs.

This means that only 2.5 seconds are needed to refresh the system data over the entire 50 km of tunnel and to authorize a new configuration.

 

Characteristics of the auxiliary network

 

2 x 225 kV / 21 RV and 132 kV / 21 kV 35 MVA sub-stations

28 x 21 kV / 3.3 kV sub-stations

148 x 3.3 kV / 400 V electrical rooms

2x6 MVA standby generator sets

3 pumping stations (400 to 750 kW)

2 x 670 mVsec ventilation and smoke extraction plants

4 cooling plants : 45 MW

2 fire safety circuits : 2 x 500 kVA

44 HV circuit breakers and 50 voltage controllers involved in the interlocking.

 

 

Text 4

 

The MMCC

 

With a floor area of almost 10 000 m2 and a volume of 58 000 m3, the printing plant is the first stage of the MMCC project. It includes a store room for reels of paper, a production shop for offset printing plates, a rotary press, a dispatch room and several technical services areas.

A rail link enables direct delivery of the reels of paper and offloading into an air-conditioned store room. The storage capacity corresponds to two months consumption, or approximately 1200 tons.

A network of conveyors feeds 7 unwinders and the offset printing machines, which comprise a Wifag rotary press, with 6 printing units driven by 180 kW motors and 2 folding machines. These machines, which are able to produce 2 newspapers of 64 and 32 pages simultaneously -with 4-colour printing on-one side and black plus a second colour on the other - at a maximum speed of 32 500 copies per hour are remotely controlled from an air-conditioned control room.

Thedispatch room has facilities for making inserts, for preparing each night the 7000 parcels of 4 to 50 newspapers, to address them and sort them according to the final destination.

The varioustechnical services rooms, house the standby generator sets and the complex power and fluid processing plants required for the operation and cooling of the rotary press together with the air conditioning of the building. These installations, designed and built by Gruenberg & Partner AG and Chaleur SA, include the dehumidified air production units for drying the output from the rotary press and the flow of iced water. Another feature is that the heating and general hot water for the building is partly supplied by heat recovered from certain parts of the. rotary press.

 

The Objectives

 

The printing plant operates 24 hours a day throughout the year. Continuity of production is therefore of paramount importance and must be ensured according to the "Just-in-time" principle. It was therefore necessary to:

optimise energy consumption round-the-clock,

ensure the safety and availability of the installations,

ensure exchange of data between complex equipment in a simple manner,

provide control, monitoring and measurement at all stages of the production process to enable follow-up at all times,

make available a reliable, effective maintenance tool.

 

The Solution

 

Based on a hierarchical automation architecture with distributed intelligence, the solution adopted by Telemecanique was designed according to the BIM 7 (Building Integrated Management) concept. It includes nine out-stations controlled by seven TSX 7 programmable controllers interconnected by a Mapway local area network, under the control of a Monitor 77 supervisor. Each out-station is a stand-alone technical island having control of the management of a number of tasks:

the air conditioning of the technical services rooms (printing plate workshop, inks and solvents, reel storage room, etc),

the ventilation of the rotary press and the air conditioning of the dispatch room (4 monobloc heating and humidifying units with variable speed pumps, lifting pumps),

the production of iced water for cooling the vital parts of the rotary press (3 out-stations for compressors, pumps, exchangers...),

the boiler room (boiler, circulators, and ventilation units) and the heat recovery unit for the compressors and refrigeration units,

the management of electrical power, its distribution, lighting circuits, load shedding, access control by badge readers, intrusion and fire detectors,

the handling of the reels from the store room, the compacted waste paper balls and the control of the standby generator sets. The programmable controllers control a number of starters, using mainly Integral 32 and 63 contactor breakers (motors, valves, flaps...), and also 8 Altivar ATV 45 variable speed controllers, via Uni-Telway data links. They also control 64 regulation loops for temperature, pressure and flow.

 

The Intelligent Building

 

The XBT-C or XBT-V operator terminals connected to the programmable controllers for local control, display values of measurements, references and action of the loops, adjust the parameters and enable selection of the mode of operation according to a pre-defined tree arrangement. But the trump card held by the maintenance and operating personnel is the Monitor 77 supervisor which enables very fine control and follow-up of all the equipment in the installation based on 70 graphic displays animated by more than 2000 objects. Real-time data, troubleshooting and rapid intervention ensure continuity of operation of the rotary press.

 

Text 5

 

The Installation

 

The computer centre is located in an large special purpose building, of which several thousand square metres are given over to computer rooms in the strict sense with the same floor space being used for technical services for the associated systems:

an incoming mains substation with several 1 300 kVA transformers

a standby power supply consisting of generator sets providing 4 000 kVA power

a group of 50 and 400 Hz inverters

a backup battery supply sufficiently autonomous to take over when the supply changes

a cold water station with four 350 kVA refrigeration compressor units

40 air conditioning units divided into two independent circuits in the computer rooms, providing a total air flow of 820 000 m3 per hour.

 

The Problem

 

The computer centre must be operational 24 hours a day, which implies:

continuous adaptation of energy consumption to the needs by load shedding and reconnecting

severe constraints of temperature and hygrometry control for the computer air conditioning

continuous monitoring of the installation : data acquisition from alarms, sensors, analogue measurement devices, as well as all of the information needed for the short term functioning and for preventive maintenance.

The Solution

 

This consists of adopting an automated production type of architecture, divided functionally into different levels :

at level 0 the sensors and actuators with the use, notably, of Integral 32 contactor breakers

at level 1, the local automatic control systems (distribution boards, standby generator sets, refrigeration units...) are controlled autonomously by more than 10 TSX series 7 PCs. The inter PC communication is provided by a Telway 7 network, which thus enables the coordination of the level 1 systems. Man-machine dialogue for this level is provided by XBT microterminals, an alpha-numerical keyboard with VDU, and two printers

at level 2, a supervisory system comprising a central programmable controller edits the data as it arrives and permits the acquisition of the operating reference values. This PC is linked with both the level 1 PCs and with the Monitor 77 supervisor.

Centralised supervision Remote surveillance

The control and supervision of the complete system is carried out by a Monitor 77, whose main functions are: animated synoptic display of the various parts of the installation, follow up of curves, storage of events. This covers more than 2 000 discrete states and 250 analogue measurements. The compute

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