GLOSARIO GENERAL

Publicamos este glosario en idioma inglés debido a que estos son términos que normalmente se encuentran definidos en textos, manuales y catalogos de productos en este idioma.

Las secciones de este glosario han sido tomadas del diccionario A&D, 2004/2005 4a Edicion de acuerdo con la información publicada en Catalogos.

Glossary
Sections of the glossary have been taken from A&D Dictionary 4th Edition, 2004/2005. With the kind approval of Prof. Dr. Eng. (habil.) Ernst Habiger, Dresden University of Technology, Institute of Automation Technologies and Publish-Industry Publishers, Munich.

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A

ACOPOS
Digital B&R servo motor drive

Access methods
Rules used, for example, by stations on a communication media to access a bus. Basically, a differentiation is made between collision [CSMA/CD, CSMA/CA] and collision-free [Token Bus, Token Ring, etc.] methods. A collision is the event when two or more stations coincidentally try to access the transfer media at the same time.
Collision-free operation is achieved by assigning access rights [token] to the individual network stations.

Activation delay
The delay time required until the brake’s holding torque is established, after the operating voltage has been removed from the holding brake.

Actuator
Actuating components for engaging a process, e.g. servo motor, switching clutch, solenoid, power switch. This involves the use of information for influencing material or energy currents in a controlled object.

Address
An address is a character string for identifying a memory location or a memory area, where data is stored and can be retrieved. It is also a symbol (e.g. with numerical controllers) for identifying a function unit for which subsequent geometrical or technological data are determined by the symbol.

Algorithms
According to DIN 19226: Algorithms are a finite series of well-defined regulations. The desired output quantities are created from permitted system input quantities. It describes how something is to be done. A procedure must at least satisfy the following requirements to be valid as an algorithm in a mathematical context.
Discreteness: An algorithm is made up of a finite series of steps.
Determinacy: Under the same start conditions, it always creates the same end result.
Clearness: The series of steps is clearly defined.
Finiteness: It ends after a finite number of steps.
From a quantity theory perspective, an algorithm is clearly defined by a set of sizes [input, intermediate and output sizes], a set of elementary operations and also by a regulation, which specifies when and in what sequence certain operations should be carried out. From a functional perspective, it transfers a set of input sizes into a set of output sizes. It can be represented in text form in a natural or artificial formal language or using graphic
representations [graph, program flow chart, structured chart, Petri Nets etc.].)

Analog digital converter
A functional unit that converts an analog signal into a digital signal

Analog signal
A signal, whose information parameters can accept any number of values, within specific technical limits. Theoretically, they can have an infinitely high resolution. However, in practice it is limited to a range of only 1 to 104. In addition, long-term storage and allocation causes many size problems. Therefore, digital signals are predominantly used in modern automation technology.

ANSI
American National Standards Institute > this organization promotes and manages American industrial standards.

APC
Automation PC

API
Application Program Interface > an interface, which allows applications to communicate with other applications or with the operating system.

Application layer
Application layer 7 for the OSI Reference Model. This is the layer where applications access network services. It provides services that directly support applications, e.g. software for data transfer, database access and electronic post.

Application software
Software, which is not used for operation by the computer itself, but rather when a computer is used to process a concrete application problem. It sets up the system software and uses this for fulfilling individual tasks.
Application software can be accommodated in standard software used by a large number of customers in a wide range of industries. Common examples are Word, Excel, PowerPoint, Paint, Matlab etc. Industrial software tailored to the respective problems of a certain industry and individual software created for solving the particular problems of an individual user.

ASCII
American Standard Code for Information Interchange used worldwide; numbers, letters, special characters and device controller characters are represented as 7-bit binary combinations. Standard ASCII-characters cover 27 = 128 characters in total. An eighth bit is used as a so-called parity bit for error detection when transferring ASCII files. During even parity checking, this bit is set to 0, when the number of ‘1s’ in the remaining seven bits
is an even number. Otherwise, it is set to 1. The expanded ASCII character set does not use parity checking. The highest value bit is used here to switch from the standard character set to the expansion. This allows space for special regional characters e.g. umlauts in the German language. www.asciitable.com

ASIC
Application Specific Integrated Circuit. At the start of the process, it represents a non-specific collection of logical gating circuits. Only at the end of the manufacturing process, is the chip adapted to the specific application.

Assembler
Mnemonic language [assembler language]. The machine instructions of a processor are expressed using mnemonics, i.e. using expressive abbreviation of alphanumeric characters. For example, when programming the command `Clear register D0´ in a normal processor system, the mnemonic abbreviation clr D0 is used instead of the binary command code 01000010 01000000. This type of programming is known as assembler programming.
The result is an assembler program. A symbolic command corresponds exactly to a machine instruction.
An assembler program is converted into bit sequences for machine codes, before the program is executed by an assembly program (also known as an assembler). It is then loaded in the program memory of the computer or controller system. In contrast to higher-level programming languages such as Pascal, C++, JAVA etc., the assembly language is processor-specific, i.e. limited to the command set of a specific processor.

Automatic mode
An operating mode, where an object [device, machine, system] operates automatically corresponding to a specified program after a start signal is issued without human contact.

Automation
According to Brockhaus: The application of technical means, using specific programs that (either partially ortotally) do not require human intervention to perform operations.Failure
Failure according to IEC 61508: A function unit loses the ability to perform a required function. In regards to safety-oriented systems, a distinction is made between dangerous and safe failures. This depends on whether the status of the system failure is considered dangerous or safe. The cause of the failure may be load related or age-related, and therefore a random failure, or related to a flaw inherent in the system. In this case, it is known as a systematic failureAutomation Runtime
A uniform runtime system for all B&R automation components.Automatic mode
An operating mode, where an object [device, machine, system] operates automatically corresponding to a specified program after a start signal is issued without human contact.

Automation Runtime
A uniform runtime system for all B&R automation components.

Availability
The probability that a system will be functioning at a certain point in time. Reliability parameter for repairable systems. The stationary availability is defined using the following formula: Availability = 1/[1 + MDT/MTBF]. To achieve the highest possible availability values, it is necessary to perfect all quality assurance measures regarding reliability. However, this procedure has its technical and economical limits for given production conditions.
When the automation plan is not sufficient to achieve the required reliability parameters, the principle of error tolerance, which is based on the shortest error detection and reconfiguration times, can allow the availability value to be increased.Failure rate Failure rate is a measure for the failure behavior of component units, particularly components. Reliability considerations are of primary interest here. The failure rate is represented by the fraction of failures for each time unit, based on the total number of a specified amount. For example, if an integrated switching circuit has a failure rate of 10-9 per hour, then this means that in a one hour operating period, the switching circuit fails with a probability of 10-9. To put it in another way: if there are 109 switching circuits in a function unit, then in the middle of each
hour, one failure is likely. The failure rate does not remain constant within the elements’ lifespan. Depending on the time, it follows the so-called “bathing-tub diagram”. This means, when a component is under the influence of early failure during the beginning of its usage, it then remains constant during a specified time span. Random failures make an appearance here, and increase again under the influence of wear-out failure towards the end of the lifespan.

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B

Backplane
Multilayer printed circuit boards with data, signal and supply lines and also slots for plug-in units on the back of electronic devices.

Bandwidth
General definition: The difference between the largest and smallest frequency in a uniform range. Bandwidth of a device: Width of the frequency band, within which device or transfer channel characteristics (e.g. the amplitude frequency characteristic) no longer deviates from reference values. Bandwidth of a signal: The width of the frequency band whose level does not exceed an agreed reference level for each of the spectral signal components.
In the context of digital data transfer, the term bandwidth is also used as a measurement for system’s performance in regards to the possible data throughput. Bandwidth here corresponds to the difference between maximum and minimum possible data rates, specified for example in bits per second.

Baud rate
Measurement unit for data transfer speed. It indicates the number of states for a transferred signal per second and is measured using the baud unit of measurement. 1 baud = 1 bit/sec or 1 bps.

Binary signal
A signal, whose information parameters can only accept two values [Low/High and 0/1].

BIOS
Basic Input/Output System. Core software for computer systems with essential routines for controlling input and output processes on hardware components, for performing tests after system start and for loading the operating system. Although BIOS is used to configure a system‘s performance, the user does not usually come into contact with it.

Bit
Binary digit > binary position, binary character, binary digit smallest discrete information unit. A bit can have the value 0 or 1.

Bit rate
The number of bits that can be transferred within a specified time unit. 1 bit/sec = 1 baud)

Bitmap graphic
A graphic, which is made up of single pixel information

Breakpoint
A point in a PLC program, where processing is stopped. This makes it possible to inspect variable values in certain locations of the program or to understand their incremental change. Breakpoints are available in CoDeSys.

Browser
A software tool for searching and reading websites. The most famous browsers are Microsoft Internet Explorer and Netscape Navigator

Bus, bus system
Bus line for transferring data and controller information between different components and systems, according to a defined protocol. A basic distinction can be made between parallel and serial buses.
Parallel bus systems have a large number of parallel lines, which allow data, address or controller information to be transferred using bit-parallel transfer. They are used as plug-in bus systems [backplane buses, backplanes] for connecting plug-in components [e.g. VMEbus, CompactPCI, IndustrialPCI etc.]. They are also used as peripheral buses for connecting computers with their I/O devices at close range.
Serial bus systems [cable bus systems] transfer data over long distances in a system between distributed system components using bit-serial transfer via a common medium [two/four conductor, coaxial cables, fiber optic cables or radio waves]. This allows a drastic reduction to be made in the wiring required in contrast to conventional star topology. Well-known examples are: AS-i, Arcnet, CAN, DeviceNet, Ethernet, INTERBUS, LON, PROFIBUS,
SERCOS Interface etc.
In contrast to office communication, where uniform Ethernet-based systems are used worldwide, many different communication systems (often incompatible with each other) are currently used in automation technology. The choice of network type usually complies with the suppliers of the control technology used in the system, the geographical region and the special functional requirements in regards to speed and network range, as well as
the availability of suitable field devices

Byte
Data format [1 byte = 8 bit] and a unit for characterizing information amounts and memory capacity. The following units are the commonly used units of progression : KB, MB, GB

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C

C
A high level language developed by Bell Laboratories that allows a computer (similar to an assembly language) to control processes. It can be translated into the machine language for all well-known computers.

C++
An expanded version of the programming language C, with object-oriented programming possibilities.

Cache
Background memory, also known as non-addressable memory or fast buffer memory. It is used to relieve the fast main memory of a computer. Data, which e.g. should be output to slower components by the working memory (e.g. disk storage, printers), is stored temporarily in the cache and output from there with an appropriate speed for the target devices.

CAE
Computer Aided Engineering > computer aided planning, construction, development and project planning (computer aided engineering in the broadest sense). The data generated goes online directly into the following areas, e.g. CAM = Computer Aided Manufacturing)

CAN
Controller Area Network serial bus system, automobile manufacturing, industrial controllers, structure according to ISO 11898; Bus medium: twisted pair. Good transfer properties in short-ranges below 40 m with a 1 MBit/sec data transfer rate. Maximum number of stations: Unlimited in theory, practically up to 64 with real-time capability, i.e. defined maximum queuing time for messages with high priority. High reliability using error detection, error handling, troubleshooting. Hamming distance: 6) www.can-cia.de

CD-ROM
Compact Disc Read-Only Memory. A removable data medium with a high capacity of ~700 MB. CD-ROMs are optically scanned.

CE Mark
A CE mark for a product. It consists of the letters ‘CE’ and indicates conformity to all EU guidelines for the labeled product. It indicates that the individual or corporate body, who has performed or attached the label, assures that the product conforms to all EU guidelines for the complete harmonization. It also indicates that all mandatory conformity evaluation procedures have taken place. www.ce-richtlinien.de

CENELEC
Comité Européen de Normalisation Elektrotechnique > European Committee for Electrotechnical Standardization (Headquarters: Brussels; responsible for the harmonization of electro-technical standards within the European Union and the entire European Economic Area [EEA]) www.cenelec.org

CiA
Established in 1992, CAN in Automation (CiA) is an international organization of users and manufacturers with a current membership of well over 300 members. It offers technical, product-specific and general information with the goal of spreading the knowledge about CAN and smoothing the way for future developments of CAN protocols. www.can-cia.de

Circuit breaker
Mechanical switching device that can switch on, allow timed operation and switch off currents under certain specified operating conditions; they can also switch on allow timed operation and switch off currents under defined exception conditions e.g. short-circuit current. They are available in open and compact designs with manual, magnet, motor or pressurized air drives; in one, two, three or four pole designs; for AC, DC and threephase current; for low voltage and high voltage applications.

Client-Server network
In contrast to a peer-to-peer network, tasks here are clearly distributed. The server offers services and the clients use these services

Closed loop control
Defined according to DIN 19226 as a procedure in which the value of a variable [control variable] is continually recorded, compared with another variable [reference variable] and changed according to the result of the comparison with the reference variable as compensation. This takes place in a closed control loop.

Code, coding
When processing information, it is often necessary to change the information from one form of representation to another. This conversion process is called coding and rules used to assign one character set to another are referred to as the code. A differentiation is made between ambiguous and unambiguous coding depending on if one set is a direct reflection of the other. Most codes use unambiguous coding with one set directly reflecting the
other. A differentiation is also made between redundant and non-redundant codes. With non-redundant codes, the full range of the available character set is used, i.e. each code is defined. With redundant codes, the available character set also contains codes that are not used. This differentiation is important during data transfer when detecting and, if necessary, correcting data transfer errors.

CompactFlash®
CompactFlash memory cards [CF cards] are exchangeable nonvolatile mass memory systems with very small dimensions [43 x 36 x 3.3 mm, approximately half the size of a credit card]. In addition to the Flash memory chips, the controller is also accommodated on the cards. CF cards provide complete PC Card-ATA functionality and compatibility. A 50-pin CF card can be simply inserted in a passive 68-pin type II adapter card. It conforms to
all electrical and mechanical PC Card interface specifications. CF cards were launched by SanDisk back in 1994. Currently, memory capacities reach up to 3 GB per unit. Since 1995, CompactFlash Association [CFA] has been looking after standardization and the worldwide distribution of CF technology www.compactflashmemory.com

Compact PCI
Compact Peripheral Component Interconnect Bus - is a registered trademark of the PCI Industrial Computer Manufacturers Group) www.picmg.org

Compiler
A program, that translates a text from a source language [normally a high level language] into the text of the target language [e.g. machine language, machine code]. That means that an executable binary file is generated from the source file on a specified processor [on a specified machine]. During this translation process, a compiler operates on several levels, in which lexical, syntactic and semantic analyses are performed. After an intermediate
code is created and optimized, the machine code is finally generated. Compilers are commonly called after the source language they process and the machine, whose machine language it translates.

CPU
Central Processing Unit – the arithmetic and control unit of a computer; the unit which interprets and executes commands. Also known as the central processor or microprocessor. A CPU has the capability to load commands, to decode and to execute, as well as to transfer information to and from other resources.

Component Based Automation [CBA]
New concept for automation applications with distributed intelligence. It is based on the new PROFInet standard from the PROFIBUS users organization and supports consequent modularization using component technology for machine and system manufacturing. A new engineering tool allows distributed applications to be merged graphically throughout the entire system. Extensive programming for communication between intelligent devices
is replaced by graphic configuration. Productivity of engineering and commissioning can be greatly increased in this way.

Continuous process
Considered to be physical procedures, chemical reactions or technological workflows with state values that continually change over time. That means energy and/or materials are fed, processed, transported, stored, distributed and/or used continually or for long periods of time without interruption, and especially for production processes, the end product is continually supplied. Such processes are characteristic for the creation, conversion and distribution of electrical energy as well as for the production, processing and distribution of bulk goods in various consistencies. Some typical characteristics of lines in which continuous processes are running are:
installed technical equipment is connected in a consistent correlation technologically; changes to procedures for incoming and outgoing materials and processes seldom take place. Examples of this are thermal power plants, energy supply systems, refineries, continuous casting lines and rolling mills. The main tasks and control applications for guidance of continuous processes are: establishing and maintaining optimal and steady operation based on specified timing criteria, monitoring and logging the process and balancing the process activities in defined areas and times for billing purposes.

Control
Targeted interaction with values in a system that can be influenced. The system being influenced is known as the controlled system and in this case is a device, machine or system in which material and/or energy are subject to one or more possible handling forms, such as extracting, transferring, converting, saving or using as desired.

CRT
Cathode Ray Tube. An integral component of a television set or a computer monitor. A cathode ray tube consists of a vacuum tube, in which one or more electron guns are installed. Each electron gun creates a horizontal electron beam, which appears on the front of the tube (the screen). The inner surface of the screen is coated with phosphor, which is lit when hit by the electrons. Each of the electron beams move in a line from top to bottom.
In order to prevent flickering, the screen content is updated at least 25 times per second. The sharpness of the picture is determined by the number of pixels on the screen.

CSMA/CD
Carrier Sense Multiple Access with Collision Detection Bus access with stochastic access, i.e. without a defined sequence for the individual participants. Using carrier sensing, each station checks whether data is transferred via the bus. If this is not the case, then a send-capable
station can begin the transfer. If two or more stations attempt to do this at the same time, a collision is caused. This is detected [collision detection] and the transfer is stopped immediately. After a randomly chosen time period has passed, each send-capable station can access the bus medium again. This allows bus access to many participants with few limitations. A central network management is not required by this process.

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D

Data link layer
Link layer/data link layer. Layer 2 in the OSI reference model. The data packets to be sent are converted into frames (i.e. logical structured data packets). Confirmation is expected for sent frames after they have been received. In the LAN area, the access procedure is also accommodated in this layer [CSMA/CD, Token Passing]

Decentralized motion control
In contrast to central motion control, only the voltage supply and the necessary components for a central controller are housed in a switching cabinet with multi-motor drive systems. All other function units such as drives and controllers are accommodated directly on-site with the individual motors or directly on the motors. They are supplied by an energy bus and a controller bus. This concept is particularly useful for larger or wide-ranging distributed machines and systems. It also provides particular advantages in regards to the modular structure of machines.

Device
In common usage, the word „device“ is a synonym for an apparatus, instrument, piece of equipment, appliance, tool or utensil. This mostly refers to fixed or mobile equipment with relatively small spatial dimensions, with a specific function or special area of use that is generally designated using a preceding word such as in the phrases sporting device, medical device, kitchen device, hearing device, measuring device, control device, automation device, peripheral device etc. Furthermore, there are fixed and mobile large devices, such as those used in the military (tanks, aircraft, ships), medical (MRI scanners), geological (earth drilling equipment, and conveyor bridges) as well as those used in research (e.g. particle accelerator). From a technical standpoint (DIN 40150), devices are made up of components, units and modules. According to regulations regarding electromagnetic compatibility of devices, a device is considered any electrical or electronic apparatus, system, construction
or network, which contains electrical or electronic parts. This device definition contradicts guidelines that are well-established and also documented in DIN standards [see above] and widely accepted by engineers, and therefore causes many misunderstandings when using the regulations regarding electromagnetic compatibility of devices.

DeviceNet™
A simple CAN-based communication system for networking automation instruments [threshold encoders, photo- sensors, motor starters, frequency controlled drives, operator terminals etc.] with higher-level control devices. Two twisted pairs inside the cable are used as the transfer medium. One is used for communication [with a transfer rate of 125 kBit/sec, 250 kBit/sec or 500 kBit/sec for cable lengths of 500 m, 250 m and 100 m] and the other is used to supply current to the connected installations [maximum 8 A at 24 V DC voltage]
www.odva.org

Dial-up
Data is transferred over the telephone network using a modem or an ISDN adapter.

Digital analog converter
A functional unit that converts a digital signal into an analog signal.

Digital signal
A digital signal has several information parameters, e.g. 8, 16, 32 or 64. These are made available in chronological succession with series signals and chronologically parallel with parallel signals. With an n-parameter digital signal, X = 2n n-digit information units [words] can be represented; for example with an 8-bit-word 28 = 256 different characters. The advantages of digital signals are the attainable high image precision [this is practically
only a question of the number of digits], the problem-free long-term storage capability and the possibility to combine many sizes with each other, while conforming to complicated regulations. This explains the strong trend towards digital technology in all areas of automation technology.

DIMM
Double in-line memory module
A memory module, consisting of one or more RAM chips on a small circuit board, which is connected with the motherboard of a computer via a connector.

DIN
Deutsches Institut für Normung (German Institute for Standardization) Headquarters: Berlin
www.din.de

Direct drive technology
In direct drive solutions, the rotational or linear motor components [torque motors, turning moment motors, DDR motors, linear motors] are integrative components for the mechanisms and machines to be driven. As a result, there is no need for couplers, gears, rack and pinions, belt and chain drives as well as spindles. This helps to avoid all side effects caused by these components (e.g. gear backlash, frictional dead spots, elasticity effects, wear, noise emissions, additional maintenance expense and space requirements). Direct Drive Technology is therefore particularly useful, if friction and wear-free movements with high precision and dynamics using compact arrangements need to be implemented. This is particularly the case with machine tools and manufacturing installations, and also in many other application areas such as medical technology for elevator and special vehicle technology.

DMA
Direct Memory Access > Accelerated direct access to a computer’s RAM through by-passing the CPU.

DNC
Direct Numerical Control. An operating mode in production systems with CNC machines. Important Features:
Central storage, management and distribution of work piece processing programs to the machine through the central computer. Modern DNC systems have a large number of additional functions such as graphic simulation of the processing procedure, storage and management of tool data and correction values, palette and work piece management, specification of processing priorities with existing work piece inventory, material flow control
through the system, convenient visualization, diagnostics etc.

DRAM
Dynamic RAM > dynamic RAM memory chips are used in capacitors as memory elements. They must be constantly refreshed to maintain the loading sequence [a thousand times a second for some]. They are cheaper but slower than SRAMs

DSP
Digital Signal Processor _ optimized for the fastest possible execution of special athematical functions, particularly with complex algorithms for analog signal processing, e.g. Fast Fourier Transformation.

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E

ECAD
Electrical CAD systems are configuration tools which allow the efficient creation and processing of electrical circuit diagrams and schematic diagrams as well as the automatic generation of cross-reference maps, cable and terminal diagrams, parts lists as well as order and manufacturing documents.

EDDL
Electronic Device Description Language

Electric motors
Electric motors are electromechanical energy converters that can operate machines and generators, i.e. driving and braking. Both possibilities can be used. There are a large number of different versions because there are electrical power systems for different voltages, frequencies and phase figures [DC, AC, 3-phase], and also because the mechanical energy in regards to its parameters [RPM, torque, force, speed] must be provided in many forms. Depending on the type of output motion, a basic distinction is made between motors for rotations and translation motions. A simple design is typically preferable for rotating drives. They are manufactured into corresponding types for the specified task and operating classes rather than for finished engineering and functional
units. In contrast, application-specific designs are dominant with linear drives. That means they are generally developed for certain applications and designed as an engineering unit with the mechanism to be driven. Depending on the stability of the output motion, a classification between continuous and discontinuous is actively possible with both rotational and linear drives. Indexed according to motion characteristics, there are four drive motor groups available. These are namely motors for continuous rotational motion, motors for discontinuous rotational motion [stepper motors], motors for continuous longitudinal motion [linear motors] and motors for discontinuous longitudinal motion [linear stepper motors]. Motors for continuous rotational movements are the mostly common used in machines at the moment. Principal Engineering Forms: In regards to the design of stators and rotors, a choice must be made between internal rotors, external rotors, bell-shaped rotors and disk
armature motors. The design of the internal rotor (stator outside, rotor inside) corresponds to standard designs. External rotor motors (stator inside, rotor outside) have a very large rotor torque and guarantee particularly low noise emission due to their very small drives. Bell-shaped rotor motors and disk armature motors have a very small rotor torque and therefore possess very good dynamic characteristics. They are preferably used as servo
motors. Speed-torque behavior: Depending on the type of current that they are designed for, and the layout of stators and rotors, three natural speed-torque behavior pattern distinctions can be made with electrical motors.

These are namely: synchronous behavior (i.e. speed remains constant within the permitted load range), shunt characteristic, (i.e. speed drops slightly with increasing loads) and series characteristic (i.e. very strong drop in speed with increasing loads). The stationary torque is created time constant with electrical motors, likewise with gas, water and steam turbines. A pulsating torque, moving around a time-based mean value, is only created with some small machines (e.g. single-phase asynchronous motors). Torque overload: All electrical motors are capable of being overloaded by torque. That means, they can emit short-term torques that are larger than the motor nominal torque NM, but however do not exceed the maximum permitted torque (Nmax) for the machine in question. The following values are common. Normal Motors: Nmax / NM = 1.6 to 2.5; servo motors: Nmax / NM = 5 to 50.

Duty Cycle Rating: Due to very strong differences with driven mechanisms and machines for time-dependent torque demand concerning the required operation mode, electrical motors are built for eight different nominal operation modes (S1 to S8, see DIN VDE 0530).Electrical safety Protection against the dangers of electricity. Safe operation of electrical and electronic modules, components, devices, machines, equipment and systems must be guaranteed for the users and operators through applicable safety regulations and standards.

Electrical safety
Protection against the dangers of electricity. Safe operation of electrical and electronic modules, components, devices, machines, equipment and systems must be guaranteed for the users and operators through applicable safety regulations and standards.

Electrical time constant
Corresponds to 1/5 of the time needed for the stator current to stabilize with constant operating conditions.

Electromagnetic compatibility
According to EMC Law: The ability of a device or a system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment [IEV 161-01-07])

Embedded systems
Systems with embedded computer functions. Included under this term are embedded chips, embedded microprocessors, embedded controllers and also embedded logic or embedded devices. These represent a large number of computer applications that are not classified in classical data processing and PC technology. Examples of these can be found in telecommunication systems, access control systems, intelligent sensors and actuators, bus modules as well as in many device and machine controllers and other applications. In all cases, it concerns microcontroller-based controller hardware, which is used for solving special problems. See above for an example. It provides task-specific I/O units and the software, which it operates with. It is stored as firmware in a read-only memory. The processing power is usually far weaker than a PC.

EMC
Electromagnetic compatibility

EN
European standard (see CENELEC)

Encoder
Coding measurement device, which converts a wave’s angular position into coded data. A basic distinction can be made between incremental and absolute systems. Based on a photo electronic high-beam scan, incremental systems deliver increments in the form of signal pulses to an evaluation electronic system [up to 10,000 pulses per rotation]. They are very well suited for recording rotation angles and rotation speeds for motion conversion but also for recording the traverse paths and speeds for longitudinal motions. A particular advantage is their simple architecture and the resulting low price. However, a disadvantage is that it can only register the position when it is switched on. The path requests a known reference point after each power-on. Absolute systems deliver the position of the wave, using a rotation, coded absolutely on the evaluation electronic system [Singleturn encoder]. They are nonvolatile as a result. A multi-turn encoder is used for absolute angular measurement with several rotations. They generally are made up of several coupled encoders with a precision gear or from a single-turn section that is coupled with a rotation counter.

Engineering
Engineering work in the broadest sense, i.e. using scientific and practical findings, concepts and methods for planning, designing, constructing and maintaining efficient hardware and software products, devices, machines and systems. In relation to corresponding attributes, the term ‘engineering’ is also used to characterize specific fields such as e.g. electrical engineering, power engineering or plant engineering.

EPROM
Erasable PROM > (complete with ultraviolet light)

EPSG
Ethernet Powerlink Standardization Group
Open association of end-users and vendor associations for the further development, standardization and distribution of ETHERNET Powerlink. www.ethernet-powerlink.org

Ergonomic
A word derived from the Greek words ‘Ergon’ [work] and ‘nomos’ [rules, law]. Part of the work sciences, ergonomics is a scientific discipline that examines the interaction between humans and their work environment. The goal is to improve the working conditions and reduce work-related stresses and strains.

ERP
Enterprise Resource Planning refers to corporate management and planning level assigned processes, i.e. the complete enterprise resource planning, optimization and management from the moment that the order is received until the goods are sent. A well-known ERP system is the software solution SAP R/3. However, there are a number of other examples of less extensive systems in regards to possible functions, where KMUs are used.

Error tolerance
A term describing the capability of a system to fulfill its specific function, even with a limited number of faulty subsystems. Error tolerant system behavior, (i.e. the preservation of the programmed functions despite the failure of system components, the occurrence of software errors or external disturbances) is achieved using redundant structures. To do this, the following redundancy principles are used. Static redundancy: function units of the redundant system are arranged in a static structure. A few examples of this include error-correction
circuits, in which faulty digital signals are adjusted based on error-correction code or comparator circuits, in which the results of three parallel functional units are repeatedly compared with each other. As long as 2 out of 3 components are functioning properly, the entire system is considered to be without error, (i.e. the failure of one functional unit is tolerated). Dynamic non-operational redundancy: individual functional units are arranged
in a changeable [switchable] dynamic structure. In the event of an error, the unit which had been performing the function is switched to a redundant functional unit. The latter does not have any functional task during error-free system operation (Stand-by procedure, 1 of 2 procedure). Dynamic operational redundancy: each functional unit in a system handles its own functional tasks during error-free operation. If one unit fails, the remaining functional units take over the failed unit‘s most important tasks by deferring some of their own tasks
that are less important for the overall function of the systems (cooperative systems, self-configuring systems, self-healing systems).

ESD
Electrostatic discharge. ESD is a process for charge equalization between solid, liquid or gaseous media, which are electrically charged in a different way. It is usually accompanied by a surface, brush, spark discharge or also flashing discharge phenomenon. However, it can also take place via a contact point (excluding line-conducted), and only when the potential difference before the contact does not exceed 330 volts. Sparking can cause flammable
gases and vapors or explosive compounds to ignite and through the discharge of currents and fields can damage or destroy electronic components or interfere with the functions of their electronic operating equipment. The first-named effect falls into the jurisdiction of Fire and Explosions Protection and Technical Safety.
The second-named area is the responsibility of the protection of Electrostatic Discharge Sensitive components (ESDS) and Electromagnetic Compatibility (EMC). Possible human body discharge from handling switching circuits, circuit boards, control elements, and container surfaces in transport, installation, testing, operating, repairs and service are particularly important issues for people dealing with electronic device technology. The following
electrical values should be calculated: Energy content 10 to 30 mJ, electrostatic voltage 0.1 to 20 kV, strength of discharge current up to 30 A (pulse amplitude, current change speed up to 100 A/ns, electrical field strength 1 to 4 kV/m, magnetic field strength up to 15 A/m within centimeters of the discharge).

Ethernet
Baseband bus system from RANK XEROX. Originally developed for linking minicomputers in the early 1970s. Ethernet is based on the CSMA/CD access procedure. Coaxial cables and/or twisted pair cables [twisted copper wire pairs] serve as transfer medium. Transfer speeds: 10 Mbps [Ethernet], 100 Mbps [Fast Ethernet] as well as 1Gbps and 10 Gbps [Gigabit Ethernet], widely growing technology used for networking computers in a LAN, standardized since 1985 [IEEE 802.3 and ISO 8802-3]. Ethernet technology has established itself in office usage.
After the enabling the possibility of extremely tough real-time demands and the adaptation of the device technology [bus cable, path fields, connection boxes] to the operational conditions of the industrial world, which are considerably tougher than those in the area of office use, Ethernet is further advancing into the area of automation technology.

ETHERNET Powerlink
An enhancement of standard Ethernet. It enables the exchange of data under strict real-time conditions with cycle times up to 200µs and jitter below 1µs. This makes it possible to apply Ethernet in automation technology at all levels of communication from the control level to the I/Os. Ethernet Powerlink was initialized by the company B&R Industrie-Elektronik and is now managed by the open end-user and vendor association, EPSG - ETHERNET Powerlink Standardization Group. www.ethernet-powerlink.org

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F

Factory automation
Automation market segment, attributed to the user sectors automotive industry, electronics industry, machine and system manufacturing, assembly/robotics, transport, storage and materials handling. The main focus of this segment includes the process chain of automated manufacturing as well as the technologies required for automation, such as mounting and handling technology, robotics, image processing, ID systems, sensors and actuators, drive technology, control technology, corresponding software, hydraulics and pneumatics as well as
the relevant safety systems.

Failure
Failure according to IEC 61508: A function unit loses the ability to perform a required function. In regards to safety-oriented systems, a distinction is made between dangerous and safe failures. This depends on whether the status of the system failure is considered dangerous or safe. The cause of the failure may be load related or age-related, and therefore a random failure, or related to a flaw inherent in the system. In this case, it is known as a systematic failure

Failure rate
Failure rate is a measure for the failure behavior of component units, particularly components. Reliability considerations are of primary interest here. The failure rate is represented by the fraction of failures for each time unit, based on the total number of a specified amount. For example, if an integrated switching circuit has a failure rate of 10-9 per hour, then this means that in a one hour operating period, the switching circuit fails with a probability of 10-9. To put it in another way: if there are 109 switching circuits in a function unit, then in the middle of each hour, one failure is likely. The failure rate does not remain constant within the elements’ lifespan. Depending on the time, it follows the so-called “bathing-tub diagram”. This means, when a component is under the influence of early failure during the beginning of its usage, it then remains constant during a specified time span. Random failures make an appearance here, and increase again under the influence of wear-out failure towards the end of the lifespan.

Fault
According to IEC 61508: Abnormal operation, which can reduce or prevent the capability of a functional unit to perform a required function.

FDD
Floppy Disk Drive. Reading device for removable magnetic memory from the early days of PC technology. Due to their sensitivity and moving components, FDDs have been almost completely replaced by CompactFlash memory in modern automation solutions.

Fiber optic cable
Cable made with glass or plastic fibers; immune to electromagnetic disturbances; very important as transfer media in local networks. All stations are completely isolated from each other. The fiber types are used. They differ regarding the transfer distances they can achieve. Polymer fibers are the simplest type. They can bridge distances up to 70m between stations. HCS fibers [Hard Clad Silica] are glass fibers with a plastic coating. They can handle distances up to 400m. Glass fiber cables are suited for distances up to 3600m.

Fieldbus
Bus system in the area close to the process, for directly connecting sensors and actuators with own intelligence. On a fieldbus, small amounts of data are transferred between sensors, actuators and control devices in digital form. Transfer must occur as fast as possible (i.e. near real-time). Furthermore, a fixed minimum and maximum response time must be guaranteed. Serial fieldbuses are replacing conventional wiring more and more in modern
automation systems. Serial networking of the components saves time during planning and installation. Additionally, the size of switching cabinets is reduced and failure and maintenance times are shortened, thereby achieving better system availability. System expansions, changes and updates are easy to implement.

File server
A computer which provides data to other users in a computer network.

Filter
In terms of suppression, filters are components used for damping conducted disturbance. Proper application of filters requires that the spectral part of the reference and disturbance variables are different enough from one another. This allows selective damping of disturbance variables without noticeable interference of the reference variables when the filter parameters have been laid out sufficiently. Therefore, the actual damping effect is achieved
mostly through voltage division and the resulting filter effect is described using insertion loss. Filters can be used on a source of disturbance to prevent the emission of conducted disturbance and on a noise reduction system to increase the immunity to conducted disturbance. In addition to the most commonly used passive filters, which are made up of passive components, there are also active filters, which contain components that require a power supply. Active filters are widely used as signal filters. They are only used in power supply networks in special cases.

Firewall
A term used for an electronic, hardware and/or software-based security system between two networks, (i.e. Intranet and Internet), which protects the computer or internal company network from unauthorized access from the Internet. Only data for specific, authorized services are allowed to pass through the security barrier at a strictly defined point.

Firmware
Programs stored permanently in read-only memory. Firmware is software used to operate computer-controlled devices, which generally stays in the device throughout its lifespan or over a long period of time. Such software includes operating systems for CPUs and application programs for industrial-PCs as well as programmable logic controllers, (i.e. the software in a washing machine controller). This software is written in read-only memory
(ROM, PROM, EPROM) and cannot be easily replaced.

Frequency inverter
A device based on power electronic semiconductor devices, which only functions in switching mode (i.e. only in on state or in off state). This device has the task (especially in speed-adjustable three-phase drive systems) of taking a single or three-phase AC voltage with constant frequency and amplitude, and making a normally threephase voltage with changeable frequency and voltage amplitude to feed the three-phase motor (synchronous
or asynchronous). The timing diagram of the voltage supplied by the inverter must be sinusoidal to the greatest possible extent, because voltage harmonics cause significant heating of the motor and increased noise formation.
Frequency inverters are offered as ready-to-use devices in multiple variations. However, their basic structure is very similar in most cases. This means that in most cases, a frequency inverter consists of a power rectifier, which converts the single or three-phase voltage of the mains into a mostly constant DC voltage (a DC bus with a larger capacitor to smooth out the voltage) and an inverter, which converts the DC voltage of the DC bus to a variable frequency three-phase output voltage.

FTP
File Transfer Protocol. Rules for transferring data over a network from one computer to another computer. This protocol is based on TCP/IP, which has established itself as quasi standard for the transfer of data via Ethernet networks. FTP is one of the most-used protocols on the Internet. It is defined in RFC 959 in the official regulations for Internet communication.

Function Block Language
FBL. Graphical programming language according to IEC 1131-3 and DIN EN 61131-3 for creating PLC application programs.

Functional safety
Safety against the dangers resulting from device malfunction (aggregate, machine, operating equipment, system).
According to IEC 61508: Part of the overall safety, based on the control object [EUC] and its control system, which depends on the proper functioning of the E/E/PE safety-related system, safety systems from other technologies and external devices for risk minimization. This is achieved while the planning, configuring, operating and maintaining the system by avoiding and/or handling potential malfunctions and by preventing dangerous system failures.

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G

Gateway
Device used to connect two networks that have different protocols. For example, when using INTERBUS a gateway represents a component, which couples other transfer systems to the INTERBUS.

GB
Gigabyte. 1 GB = 1,073,741,824 bytes

GIF
Graphics Interchange Format. Graphic format with up to 256 colors in which images are compressed to a minimum size. GIF files are well-suited for images with sharp color transitions.

Ground
In the context of electro-technical theory, the term ‘ground’ is more or less understood as good conductive ground, which does not have any potential differences outside the area of influence or any other electrical phenomena.

GUI
Graphical User Interface. A display seen by a computer user with icons for various utilities and programs, including display and operational elements for programs or operating systems, menus and dialog boxes, which make it easier for the user to operate the computer.

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H

Half duplex
Method of data transfer in which information is transferred in both directions consecutively.

Handshake
Method of synchronization for data transfer when data is sent at irregular intervals. The sender signals that data can be sent and the receiver signals when new data can be received.

HDD
Hard Disk Drive. Fixed magnetic mass memory with high capacities e.g. 120GB.

Hexadecimal system
Number system with the base B = 16. It has sixteen digits [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, (10), (11), (12), (13), (14), (15)] which are often represented with letters for elements (10) to (15) [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F].
The sum of the products for a hexadecimal number is calculated as follows
Z = zn16n + zn-116n-1 + ... + zi16i + ... + z1161 + z0160.
For example, value Z for the hexadecimal number 5A2FD is calculated as follows
Z = 5_164 + 10_163 + 2_162 + 15_161 + 13_160

HMI
Human Machine Interface

Horizontal integration
Horizontal integration combines MES solutions with each other in a company pyramid. In this way, all information is available online which prevents multiple data entry and double data storage.

Host
On computer systems with multiple CPUs and bus masters, this refers to the device with the arbitration unit and host CPU or the device that has control of the entire system. With regard to the Internet, a constantly available network server is called a host.

Hot swap
Changing computer components during operation. There are three different level: basic hot swap, full hot swap and the high availability model. Basic hot swap is the simplest form in which the module to be exchanged is deactivated or the computer configuration is changed using the computer keyboard. Computer specialists are normally needed. With full hot swap, software installed on the components being exchanged handles activation and deactivation. An integrated switch on the front of the component signals the computer that removing the
component will start or that inserting the new component is complete. An LED on the front side shows that the component can be removed or that the new component has been inserted. The high availability model is used in computer systems with high availability requirements. Here, the hot swap software does not control each component individually, instead it uses a separate hot swap controller [HSC]. This allows faulty boards to be
automatically deactivated and prevents crashes.

HTML
Hyper Text Markup Language. Programming language with hyper text marks. Language used to write most web pages. It is based on the SGML definition. For detailed information, see www.w3.org/MarkUp

HTTP
Hyper Text Transfer Protocol. Data transfer protocol for HTML pages and all types of files coupled to them. It is the protocol that the entire WWW is based on. That means, it controls the interaction between web browser and web server. It becomes active with each mouse-click on a hyperlink and ensures that the browser is provided the respective information.
www.w3c.org/Protocols

Hub
Central connection point in a network with star formed topology, which distributes incoming data packets to all connected end devices [similar to the way a multiple power socket distributes power].

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I

IAONA
Industrial Automation Open Networking Alliance. Group of leading international automation manufacturers that distributes open IT network standards such as Ethernet as worldwide standards for industrial communication. Founded in 1999 at the SPS/IPC/DRIVES in Nuremberg. www.iaona.org

IDE
Integrated Device Electronics. Interface for mass memory, such as HDDs, in which the controller electronics are found in the drive itself.

IEC
International Electrotechnical Commission. International standards organization that includes all national electrotechnical committees. It specifies electro-technical standards worldwide; location: Geneva. www.iec.ch

IEEE
Institute of Electrical and Electronics Engineers. American organization of electrical and electronic engineers (founded in 1884, more than 300,000 members in approximately 150 countries) www.ieee.org

IL
Instruction List. IL is a text-based, assembly-like programming language according to IEC 1131-3 and DIN EN 61131-3 for creating PLC application programs.

Intelligent systems
Before continuing, it should be noted that it has not been possible to make a generally accepted, clear definition for intelligence, neither for psychology nor technology. However, the following is a very simplified statement concerning the many perceptions that exist, starting with a reference to the intelligence of humans: „Intelligence [mental capabilities] refers to the ability to effectively cope with tasks in life and on the job“. It is many-facetted personal trait that is mainly based on the ability to think (i.e. dealing with information rationally and emotionally).
The main and partially measurable factors include: perception, processing of information, storing of information, language, mathematics, imagination, concentration and judgment. If intelligent technical systems are evaluated according to these criteria, it is clear that they surpass human abilities in certain areas, but have huge shortcomings with reference to total intelligence. That means such systems are still far from achieving the complex intelligent capabilities of humans, but support them in a significant manner, and that is the most important factor affecting the functional quality and marketability of intelligent components, modules, devices, machines and systems. Their strengths come from the use of fuzzy technologies and artificial intelligence methods for collecting information, planning actions and monitoring results, even when the conditions are not clearly defined. Areas of application include: Handwriting and voice recognition, image processing, robotics, sensor and actuator control, adaptive control and planning systems, knowledge acquisition and processing, data mining as well as assistance systems for planning, maintenance, diagnostics and project management.

Interface
From the hardware point of view, an interface is the connection point between two modules/devices/systems. The units on both sides of the interface are connected by the interface lines so that data, addresses and control signals can be exchanged. The term interface includes all functional, electrical and constructive conditions [coding, signal level, pin assignments], which characterize the connection point between the modules, devices
or systems. Depending on the type of data transfer, a differentiation is made between parallel [e.g. Centronics, IEEE 488] and serial interfaces [e.g. V.24, TTY, RS232, RS422, RS485], which are set up for different transfer speeds and transfer distances. From the point of view of software, the term interface describes the transfer point between program modules using specified rules for transferring the program data.

Internet
International Network. Worldwide collection of computers and computer networks of various sizes and architectures that work with various operating systems. Information is stored remote computers [servers] that can be accessed by anyone at any time from their computers [clients]. It has developed in steps in resent decades and now is the basis for the worldwide exchange of data, for example via e-mail. It is currently the most popular network in the world with approximately 500 million users. www.isoc.org

IP
Internet Protocol. Protocol [method, procedure] used to transfer data from one computer to another in a network, for example on the Internet or Intranet. Each computer in the network is clearly identified by its IP address. If data is sent from one computer to another, it is broken into small information packets containing the address of the sender and receiver. These packets can reach their destination over the network using different paths and
in an order other than the send sequence. Once there, they are put back in the correct order by another protocol, the Transmission Control Protocol [TCP].

IP protection
It uses IEC 529, EN 60529 or DIN EN 60529 to characterize the protection of electrical devices by housings, covers or encapsulating to prevent persons from accessing dangers parts within the cover and provide protection from contaminants and water. The protection code is specified by a 4-character code [IP code]. It consists of the letters IP and two numbers. IP stands for „International Protection“, the first number specifies protection against solid contaminants (0 to 6), the second number specifies protection against water (0 to 8). The individual degrees of protection range from simple protection against touch to full protection against dust as well as from protection against vertically dropping water to protection against being fully submerged. In industrial environments, protection levels starting with IP 65 have become standard.

IPC
Industrial PC

ISA
Industry Standard Architecture. Early bus system for expansion slots allowing installation of add-on PC cards. In modern PC architectures, it has mostly been replaced by the PCI bus.

ISO
International Organization for Standardization. Worldwide federation of national standardization institutions from over 130 countries. ISO is not an acronym for the name of the organization; it is derived from the Greek word isos, meaning „equal“. www.iso.ch

IT system
Information Technology system. Technical system for evaluating, transferring, processing, storing and/or using information.

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J

Jitter
Jitter is a term that describes time deviations of cyclic events. If, for example, an event should take place every 200_s and it actually occurs every 198 to 203_s, then the jitter is 5_s. Jitter has many causes. It originates in the components and transfer media of networks because of noise, crosstalk, electromagnetic interference and many other random occurrences. In automation technology, jitter is a measure of the quality of synchronization
and timing.

JPEG
Joint Photographic Experts Group. Widely-used graphic format for compressing digital color and black/white pictures. Named after the expert group that created it.

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L

LAD
Ladder Diagram. Graphical programming language according to IEC 1131-3 and DIN EN 61131-3 for creating PLC application programs.

Latency period
Synonym for delay time, reaction time and runtime. For technical purposes, the time a device requires to provide an output reaction after an input arrives or, for example, the time a data packet requires to pass from the sender to the receiver on a network or remains in a network device before being forwarded.

LCD
Liquid Crystal Display. LCDs are not lit themselves, they reflect light from their environment or allow light to pass through from behind.

LED
Light Emitting Diode. Luminescent diode.

Linear motors
All motor technologies that are used to create rotary electric motors can also be used in a linear (straight) arrangement to create linear motors. As standard synchronous motor or asynchronous motor designs, a linear motor consists of two parts; an m-strand winding packet [primary side or forcer] embedded in grooves in a metal plate or molded in plastic (iron-free) and a secondary side that either consists of a carrier rail where the permanent magnets are mounted [synchronous motor] or a squirrel cage winding placed in a magnetic frame [asynchronous motor]. Linear motors are available in flat and cylindrical designs, are air and water cooled and have different guidance systems [glide, air suspension, roller, magnet, etc.]. They are used for translatory direct drive technology. They allow immediate, low-wear, low-vibration force to be applied to machine parts that move lengthwise without having to convert a rotary movement. Together with high resolution sensor systems, powerful controllers and precision bearings, they are very well suited for linear positioning and feed movements that are highly dynamic and extremely precise. In high-end applications for measurement, optics and electronic manufacturing, they allow positioning precisions <1 _m. For general use in machine manufacturing, precision requirements of 0.01mm to 0.1 mm are necessary in addition to being robust, having a long lifespan and being able to be easily integrated in the construction and control technology for machine concepts. A special linear
motor application is the drive system for the Transrapid.

Low-voltage guidelines
The goal of the guideline is to guarantee the safety of the user and to minimize the incidents of accidents. This includes all electrical operating equipment for creating, conducting, distributing, saving, converting and consuming energy such as e.g. generators, cables, switches, sockets, accumulators, transformers, lights, household devices and motors for using with a nominal voltage of between 50 and 1,000 volts for AC and between 75 and
1,500 volts for DC. Exceptions are listed in Appendix II of the guidelines. According to the guidelines, such operating equipment should only be put into circulation when it has been manufactured in compliance with current EU safety engineering regulations, when it will not injure or damage humans, animals and material assets with proper installation and maintenance and usage according to regulations, when a conformity evaluation process
has been undertaken by the manufacturer, when a corresponding declaration of conformity is available and finally when they are labeled with the CE marking.

LPT
Line Printer. Logical device names for printers on PC systems.

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M

Machine
According to machine regulations, a machine is understood to be an entire collection of interconnected components, with at least one being movable. Along with the mechanical components, the actuator, controller and energy components are also part of a machine. See also Automation Object.

Machine guideline
Machine guideline 89/392/EWG has the task of ensuring the free movement of goods for machines in the European Union (with this machine systems and removable equipment are also meant), separately introduced safety components as well as load absorption equipment. This has led to harmonized structural demands and conformity evaluation processes, which must be fulfilled by the people responsible for this. This particularly concerns safety requirements and health protection in relation to machine construction.
www.maschinenrichtlinie.deManufacturing automation Automation market segment for the industrial sectors such as circuit, component, device and aggregate manufacturing, in which primarily discrete processes (discontinuous processes) occur.

Master-Slave principle
The master-element determines that slave-elements follow the instructions of the master. With remote bus control, an automation device as master-element grants the access rights for the other components [slave-elements].

Maximum speed
Maximum motor speed. This is a mechanical condition (centrifugal force, bearing wear).

MB
Megabyte (1 MB = 1,048,576 bytes or 220)

Mechatronics
Mechatronics was coined from the terms mechanics, electronics and informatics, and is a multi-disciplinary area of engineering that integrates these three areas. Established in Japan in 1975, it is an interdisciplinary development approach for products, which provides solutions for mechanical product tasks through the dimensional, technological and functional integration of mechanical, electrical and information processing subsystems.
Completely new products or products with considerably improved features have been developed as a result and this trend will continue into the future. Examples of mechatronic systems are: motor vehicles, aircrafts and spacecrafts, ships, modern rail traffic systems, machine tools, robots, modern cameras and many other devices and systems where the close interplay of mechanics, electrics and electronics is an essential requirement for their functionality.

MES
Manufacturing Execution System. The term MES covers a series of software solutions at factory control level. Its task is to record, prepare and make appraisable, all production data for optimizing production processes. By using real-time data from production, MES systems allow monitoring, control, reaction and reporting for the respective processes as they occur. This makes it possible to react quickly to changing manufacturing conditions in relation to the reduction of non-relevant production activities, and allows a more effective management of operation and production processes. In the context of vertical integration, Manufacturing Execution Systems are the link between the Automation level and management level systems [business corporate planning, ERP].

Microprocessor
Highly integrated circuit with the functionality of a CPU, normally housed on a single chip. It comprises a control unit, arithmetic and logic unit, several registers and a link system for connecting memory and peripheral components. The main performance features are the internal and external data bus and address bus widths, the command set and the clock frequency. Additionally, a choice can be made between CISC and RISC processors.
The first commercially available worldwide microprocessor was the Intel 4004. It came on the market in 1971.

MIPS
Million Instructions Per Second. A measurement unit for measuring the operating speed of a computer.

MIS
Management Information System. The goal of such systems is to provide computational and simulation technology support to management processes such as planning, monitoring, and decision making, in order to improve overall quality. This requires that all company data relevant to decision makers can be accessed and that this data can be incorporated into planning, control, and simulation processes. The performance capability of today’s systems largely depends on the provision of filtered, processed, compressed information and successcritical data, within the shortest period of time. It is also very dependent on the information and organization structures within a company.

Modem
Modulator/Demodulator. An add-on card or external device, which allows information to be exchanged between computers over the telephone network using digital/analog or analog/digital signal conversion.

Motherboard
A circuit board, which houses the main components of a computer such as the CPU switching circuit, co-processors, RAM, ROM for firmware, interface circuits and expansion slots for hardware expansions.

MTBF
Mean Time Between Failures. The mean time between two failures for repairable objects and reliability parameters.

MTC
Maintenance Controller. A standalone processor system in B&R industrial PCs, which provides additional functions for system monitoring and availability.

Multiplexing
A combination of two or more information channels on a common transfer medium.

Multitasking
Multitasking is an operating mode in an operating system, which allows several computer tasks to be executed parallel and simultaneously.

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N

NAMUR
NAMUR is a German standardization association for measurement and control technology in chemical industries. It was founded in 1949. The subheading “Interest Group for Process Control Technology in the Chemical and Pharmaceutical Industries” has been added to make it more relevant to today’s situation. NAMUR is an association of users of process control technology. Manufacturers of control technology, hardware and software are not eligible as members. There are currently over 80 member companies from Germany and other European countries such as Spain, Austria, Hungary, Switzerland, Belgium and the Netherlands. It is concerned with planning and erection, with solutions and systems for process control and factory control levels, with measurement and positioning technology and also with the operation and technical support of process control equipment up to closure.
www.namur.de

NC
Numerical Control

.NET
DOTNET. Microsoft’s new development platform provides a common runtime library and a type system for all programming languages. DOTNET is the umbrella term for the following products, strategies and technologies; .NET framework, a new software platform, Visual Studio .NET, a new development environment that supports several .NET programming languages (e.g. C# or VB.NET especially created for .NET), .NET My Services, a group of services taking over functions such as authentication, .NET Enterprise Server, which apart from the names, is independent of the other technologies and includes the products Exchange Server 2000, Application Center 2000, SQL Server 2000. .NET devices, supported by a slimmed down version of the .NET framework (.NET Compact Framework.)

Network
A connection structure of individual elements [points, nodes, components] that are connected with each other or have a defined interaction with each other [traffic systems, power supply networks, communication networks etc.]. In the context of the EMC law, for example, this is understood as a summary of several transfer lines, that are electrically or optically connected to the individual points [nodes] using an installation, a system, an
apparatus or a component. Of particular importance for modern automation technology are the communication networks like the Internet, Intranet, Ethernet etc.

Network layer
Layer 3 in the OSI reference model. The data packets are addressed in this layer. Logic addresses and names are also physically converted and the transfer paths defined.

Node
Branching point in a network

Numerical controllers
NC and CNC systems are high-capacity programmable logic controllers based on the microcomputer, used for automating operating sequences, particularly with processing and converting machines, but also with polygraph machines and measurement, testing and drafting machines, as well as many other installations. In a modified form they are used to control manipulation processes for industrial robots. Corresponding to the characteristic
special features of the movements in the controlled object, a distinction is made between the items controllers, linear path controllers and two or multi-dimensional continuous path controllers. They are numerical controller systems, housed on the operator panel and console for the machine to be controlled or accommodated on a separate vessel. The processing programs for individual work pieces – depending on the type and scope of
the processing task, they consist of between 50 to 500 individual program sentences. Each sentence contains the necessary geometrical and technological data for executing a technological sub-operation. They are coded alphanumerically using keyboards [work station oriented programming WOP] or memory or entered online by a higher-level control computer [DNC computer] in the internal controller work data memory. The process sizes for important control process [tool positions] are recorded with discrete measuring instruments and processed numerically together with the program information; i.e. the command information is created for main and auxiliary drives in the controlled machine.

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O

Object
Something toward which thought, feeling, or action is directed. In the context of software, it is a self-contained unit that contains specific data [attributes] and functions [operations].

ODVA
Open DeviceNet Vendor Association. An independent organization that supports the further development, application and spreading of DeviceNet worldwide. Membership is made up of companies who either manufacture DeviceNet products or supply development tools for DeviceNet. www.odva.de

OEM
Original Equipment Manufacturer. A company that integrates third-party and in-house manufactured components into their own product range and then distributes these products under its own name.

OMAC
Open Modular Architecture Controls Users Group. An association, which promotes the worldwide development and application of open modular architecture controls.
www.omac.org

OOP
Object Oriented Programming. New procedure for creating software. At the core of this procedure are objects that incorporate data and processes for manipulating this data. If the following circumstances apply then it is an example of OOP: Encapsulation: Hides the data structure of an object from the user and caller. Defines similar objects into classes. Inherits methods and capabilities of an object developed to the later model [equal treatment].
Compatible to both the original and the later model [polymorphism].

OPC
OLE for process control. A communication standard for components in the area of automation. The goal of OPC development is to provide an open interface that builds on Windows-based technologies such as OLE, COM and DCOM. It allows problem-free standardized data transfer between controllers, operating and monitoring systems, field devices and office applications of different manufacturers. This development is promoted by the OPC foundation, which is made up of over 200 companies from around the world, including Microsoft and other leading companies. Nowadays, OPC is also interpreted as a synonym for Openness, Productivity and Connectivity, symbolizing the new possibilities that this standard opens up.

OPC server
The missing link between connection modules for the InterBus and the visualization. It communicates serially with the connection modules via the ISA or PCI bus or Ethernet.

Operating system
The entire collection of programs, which together with the computer’s hardware, regulate the basic operating sequence of a computer and computer-based devices.

OSI reference model
Established in 1972 by the ISO, its goal is to link the networks of different manufacturers with the different topologies. The OSI reference model [also known as a layer model] represents a standard, which classifies and defines the principles for which communication, using different protocols (rules), takes place between the components in a network. It consists of seven layers in total: Physical layer, data link layer, network layer, transport
layer, session layer, presentation layer and application layer. Using the lowest layer, the physical [layer 1], the electrical and mechanical specifications for cables and network adapter cards are defined, as well as the method for sending bits over the cable. The second layer, the data link layer, integrates bits from the lowest level into groups and data packets [frames], and inserts controller information at the start of the packet [sender and receiver
address, length of the packet, used protocols of higher layers]. At the next highest layer, the network layer [layer 3], information is passed on over the network used and so on.

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P

Parameter data
Represents configuration values and device data, e.g. configuration values of components. The data is stored in the central controller and if necessary, can be automatically downloaded after the exchange of individual components. That means, parameter data rarely changes and is only transferred when requested. Concerning transfer speed, the data is governed by less stricter requirements in comparison to process data.

Parity checking
Parity checking is a simple process that checks for transfer errors. The parity bit is added so that each group of bits (containing the number of 1s) has either an even or odd number of bits (HD = 2).

PC card
Registered trademark of PCMCIA for add-on cards conforming to PCMCIA specifications.

PCI bus
Peripheral Component Interconnect Bus. Developed by INTEL as an intermediary/local bus for the latest PC generation. It is basically a synchronous bus. The main clock of the CPU is used for synchronization. The PCI bus is microprocessor independent, compatible with 32-bit and 64-bit and supports both 3.3 V and 5 V cards and devices. See also PCI SIG.

PCMCIA
Personal Computer Memory Card International Association. An international standards body made up of component manufacturers in the computer industry that support the establishment and further development of a standard for memory cards and other PC cards. The corresponding PCMCIA standard provides exact specifi- cations for details such as size, power consumption, signal handling and programming of the cards. The cards have compact dimensions [credit card format, 3.3mm, 5mm or 10.5 mm thick], low power consumption and are configured using software. PCMCIA technology is well suited for all mobile measurement, analysis, service and testing systems equipped with mobile PCs, laptops or notebooks.
www.pcmcia.org

Physical layer
Layer 1 in the OSI reference model. It defines network cabling and transfer technology and regulates the transfer of bit streams over a physical media from one device to another.

PICMG
PCI Industrial Computers Manufacturers Group. Goal: Use of commercial PCI bus for industrial environments, especially CompactPCI bus. www.picmg.org

PID controller
PI controller with derivative element. The derivative element additionally influences the manipulated variable to the same extent as the change speed for the control deviation.

PLC
Programmable logic controller. Computer-based control device that functions using an application program. The application program is relatively easy to create using standardized programming languages [IL, FBD, LAD, AS, ST]. Because of its serial functionality, reaction times are slower compared to connection-oriented control. Today, PLCs are available in device families with matched modular components for all levels of an automation
hierarchy.

PLCopen
PLCopen is a vendor and product independent worldwide association that supports the establishment of international standards, especially IEC 61131-3, for programming industrial controllers and certifies standard-based programming systems. This includes the definition of various compliance levels, as well as the development of test procedures and provision of certificates from independent institutions. plcopen.org

Polling
Method of synchronization for data transfer. When polling, one partner [master] cyclically asks other partners [slaves] if they want to send information or if they can receive information. Only the master can start communication, not the partners [slaves] being polled. They can only block communication.

Power electronics
Technology based on power semiconductors that can switch high currents and handle high voltages [e.g. IGBTs] for conversion, control and conditioning of energy. Power electronic components and devices rated up to the megawatt range can be found in the supply systems of nearly all electric/electronic equipment. According to experts, over 50% of the worldwide electric power consumption was controlled using power electronic devices
and systems in year 2000.

Power Panel
Devices from this B&R product family combine visualization, control and I/O components in one compact device. Powerlink (see ETHERNET Powerlink)

Presentation layer
Layer 6 in the OSI reference model. This layer handles text formatting and display. It is also responsible for data security. It handles data compression as well.

Process
Action, event or procedure in which continuous or discontinuous, quantitative or qualitative changes to parameters or states of a real or virtual object or media being observed take place. Every process has a defined start and a defined end. Depending on what happens during a process or which objects undergo the process, it is possible to differentiate between many types of economic and industrial processes such as value-added processes
[production and manufacturing processes], service processes [logistics, maintenance and repair processes], management processes [planning and maneuvering processes], etc. For technological processes, a differentiation is often made between continuous processes, discontinuous processes and charge processes depending on the continuity of the main process activity.

Process image
Image of the signal states for digital inputs and outputs on the PLC CPU. The process image for inputs and the process image for outputs are differentiated.

Process visualization
Display of the activities in an industrial production area, in communal areas, in traffic areas and in safety relevant or laboratory areas using modern IT equipment, i.e. suitable display systems for improved handling of the respective processes.

PROFIBUS-DP
PROFIBUS for „Decentralized Peripherals“. PROFIBUS-DP can be used to allow simply digital and analog I/O modules as well as intelligent signal and data processing units to be installed in the machine room, which among other things can significantly reduce cabling costs. Many used for time-critical factory automation applications.

Programming languages
Programming languages are artificial languages with strict syntax and semantics, clear symbols and special notation for creating algorithms in an executable computer program. Since the creation of the first functioning program-controlled computer Z3 in 1941, over a thousand programming languages have been developed for various application areas. An overview of the evolution, current state and future of programming languages can be found on the following websites.

Protocol
Information technology (IT): Specifications regarding data formats and control procedures for communication between two devices or processes. The protocol can be implemented as hardware or software and mainly includes the following aspects: the type of error detection used, the data compression method (if used) and the way the sender indicates the end of the information sent and the receiver indicates that the information has been received.

PV
Process variable. Logical storage location for values and states in a program.

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R

RAM
Random Access Memory. A semiconductor memory which can be read or written to by the microprocessor or other hardware components. Memory locations can be accessed in any order. While ROM types cannot be written to, RAM memory allows both read and write access.

Rated current
The rated current is the effective value for the phase current (current in the motor supply line) when generating the rated torque at the rated speed. This is possible for any length of time if the environmental conditions are correct.

Rated power
The rated power is output by the motor when n = nN. This is possible for any length of time if the environmental conditions are correct.

Rated torque
The nominal torque is output by the motor (n = nN) when the nominal current is being drawn. This is possible for any length of time if the environmental conditions are correct.

Real-time
A system is operating in real-time or has real-time capability, if the input sizes [e.g. signals, data) are received and processed in a defined time period, and the results are made available in real-time for a partner system or the system environment. See also ‘Real-time Demands’ and ‘Real-time System’

Real-time classes
The real-time demands on computer, control, controller and communication systems are defined by the physical environment that they operate in and by the partner system that they interact with. To clarify these facts about orientation in a more technically way, the IAONA real-time work group carried out a classification of networks for real-time environments. This resulted in the development of four distinct real-time classes. Class 1 covers all installations and systems where relatively slow (not time critical) processes take place. With integrated communication systems, this means reaction times ranging between 0.1 and 10 seconds. Class 2 refers to a dynamic relatively simple usage environment, where reaction times between 1 and 500 ms are sufficient. Class 3 concerns dynamically simple devices and systems such as robots and CNC machines, which due to the communication technology demand reaction times of approximately 50µs to 20 ms. Class 4 focuses on highly-dynamic installations and systems, whose communication network requires reaction
times of well below one millisecond to ensure flawless operation. www.iaona.org

Real-time system
A system, which responds to an outside event within a specified time period. Therefore, the main focus is not on speed. The necessary reaction speed conforms more to the environment and to the partner object, which the system cooperates with in a specific application. For example, high-speed digital controllers need real-time systems, where reaction times lie in the microsecond range. In contrast, automation solutions with programmable logic controllers can manage with reaction times in the millisecond range. For slow systems in the processing industry, e.g. temperature controllers, reaction times in the range of seconds or even minutes are sufficient. In regards to complying with the defined time limit, a distinction is made between critical and relaxed real-time demands. A critical real-time demand is when all required system responses to an outside stimulation must be
made within a strictly specified time period under all possible conditions. Otherwise, considerable damage is imminent. In contrast, a relaxed real-time demand is where there is a certain degree of tolerance involved. A defined time limit can be exceeded, because there are no fatal consequences to fear. The real-time capability of a system depends on a number of variables. Particularly in Automation technology, signal running times, cycle
times, latency periods, jitter, synchronicity requirements and data throughput to be managed play a significant role.

Redundancy
Technical equipment or methods exist beyond that necessary for completing a function for the purpose of increasing functional security of devices and systems.

Relay
An electric device that causes a defined change in one or more electrical output circuits when a change occurs to a value on the input circuit [current, voltage or their derivatives over time, as well as the sum, difference, product or quotient of several electrical values]. The following types are differentiated between according to DIN VDE 0435 depending on their functioning principle: Electromechanical relay, if they function according to the movement of mechanical elements resulting from the effects of an electric current on the input circuit; Electrothermal
relay [thermal or bimetal relay], if they function according to the deformation of thermal elements (directly or indirectly caused by the bimetal strips being heated by the input current); Static relay, if they function according to electronic, magnetic, optical or other methods without moving mechanical elements or thermal elements. Switching relays and measurement relays are also differentiated between depending on their use. Switching
relays are used as control relays, auxiliary relays, intermediate relays, timing relays, stepping relays, indicator relays and in other specifications for creating simple control applications. Measurement relays are used as protective relays, overload relays, monitoring relays, differential relays, distance relays, negative-phase-sequence relays and in other designs as monitoring, protective and diagnostics functions.

Release delay
Delay time required until the holding torque of the holding brake is reduced by 90% (the brake is released) after the operating voltage has been returned to the holding brake.

Reliability
In a technical context, reliability represents the ability to correctly operate at a continual performance level within defined probability limits and time spans. Characteristic reliability parameters are: MTBF of repairable devices, MTTF for non-repairable systems and failure rate for modules or components, which can be used to establish availability.

Repeater
Equipment used to amplify and regenerate signals in a network. Information passed through a repeater can travel longer distances than without a repeater. Simple, cost-effective method of LAN expansion.

Residual risk
Risk that remains after applying appropriate protective measures

Resolver
Inductive devices used for determining and transferring rotation angles. Modern designs can have a precision of +/- 3 angular minutes. They are used to create highly dynamic drive solutions. They are constructed as small precision alternators with a single-strand rotor winding and a double-strand stator winding, which has strands that are offset 90 degrees in the stator. If the rotor winding has an AC voltage applied (normally 10 kHz) with constant
amplitude, voltages with the same frequency are induced as in a transformer to the two stator windings, having amplitudes that are proportional to the sine and cosine of the rotor rotation angle. The rotor rotation angle can be determined using these amplitudes and an arc tangent calculation. That means the resolver works in this case as a rotation angle encoder. If the two stator windings have AC voltage applied, having amplitudes proportional to the sine and cosine of a desired angular set value, a voltage is created in the rotor that corresponds to the difference between the rotation angle set and actual values. In this case, the resolver functions as a rotation angle encoder with integrated set and actual value comparison.

Robustness
Ability of an object to continue functioning, even if specified conditions are not met. Qualitative term because exact assessment criteria do not exist.

ROM
Read Only Memory. Nonvolatile memory. Contents of the memory are stored by the chip manufacturer in final mask step [also called mask-programmed ROM]. It can only be read and constantly remains in the same form.

RS232
Recommended Standard Number 232. Oldest and most widespread interface standard, also called V.24 interface; all signals are referenced to ground making this an unbalanced interface. High level: -3 ... -30 V, Low level: +3 ... +30 V; cable lengths up to 15 m, transfer rates up to 20 kbit/s; for point-to-point connections between 2 participants.

RS422
Recommended Standard Number 422. Interface standard, balanced operation resulting in increased immunity to disturbances. High level: 2 ... -6 V, Low level: +2 ... +6 V; 4-wire connection [inverted/not inverted], cable lengths up to 1200 m, transfer rates up to 10 Mbit/s, 1 sender can carry out simplex communication with up to 10 receivers.

RS485
Recommmended Standard Number 485. Interface standard upgraded from RS422; High level: 1.5 ... -6 V, Low level: +1.5 ... +6 V; 2-wire connection [half duplex operation] or 4-wire connection [full duplex operation]; cable lengths up to 1200 m, transfer rates up to 10 Mbit/s. Up to 32 participants can be connected to an RS485 bus [sender/receiver].

Runtime system
For computer technology: All routines required to execute a program written in a special programming language on a special platform [interaction with the operating system, memory management, error handling routines, etc.]. For automation technology, there are now many manufacturer-specific runtime systems for practically all controller types [PLC, CNC, PC-based system, robot controllers, etc.]. In distributed automation systems, flexibility, functionality and performance of the individual devices is often limited. It seems that using the. Net
technology from Microsoft, including the CLR (common language runtime) system, can help. For communications, a runtime system is a filter for signal correction that removes disturbances that cause sections of wireless signals for example to be distributed in different ways with different runtimes causing signal distortions for the receiver.

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S

Safety
According to Brockhaus: The absence of danger or the knowledge that an individual or group is protected from potential dangers. When referring to technology, safety is the characteristic of an object [component, device, machine, system] to not present unacceptable dangers to people, equipment or the environment when operated according to specifications. Handling security issues takes place in two ways: Firstly, under the premise that the object will function as it should; secondly, under the premise that the object will not function correctly (complete
failure). The first aspect mainly concerns issues of health, working conditions and fire and is regulated by many laws and guidelines. The second aspect is part of technical safety measures that are set up to minimize dangerous situations and risks associated with system failures (at least below an acceptable limiting risk level) based on the probability of a failure and the possible extent of damages. These issues are included in the topic of functional safety. For automation technology, the corresponding standards are IEC 61508 and EN 954-1. As a footnote, there is no such thing as absolute safety without any risks, neither in technology or nature.

SCADA
Supervision, Control And Data Acquisition. SCADA systems are used to control, monitor and record industrial processes. A high degree of configurability allows customization for various processes.

SDRAM
Synchronic Dynamic Random Access Memory. A form of dynamic RAM semiconductor modules that can be operated at high clock rates.

Sensor
Equipment that converts a physical value based on a physical effect into an electrical, pneumatic or hydraulic signal for further processing. Modern sensors have integrated signal preprocessing to prevent disturbances or nonlinearity. In automation technology, sensors are used to get the information required to control a process. For example, determining aggregate and machine states or to collect process data such as temperature, pressure,
speed, fill level, flow, distances, angles, etc.

Sequential control
Sequential control is a control sequence where the individual steps are structured and processed sequentially in accordance to the plan/program stored in the control device. The individual steps are assigned commands, which are output to the control object by the control device as either time-dependent or process status-dependent. This is determined when both the specified timing conditions for one step are fulfilled or if stipulated events have occurred in the process range. On the basis of this fact, there is a differentiation made between
time-dependent sequential control and process-dependent sequential control. Time-dependent sequential control is used where it can be safely assumed that the sequences in the controlled object are always processed according to the time function, or where important criteria for the processing sequence either cannot be recorded or only recorded with great difficulty in a metrological manner. For example, it can be found in starter automation for motors, which always start under the same stress ratios and also in automation for controlling washing machines, centrifuges, molding machines, injection molding machines and contact welding machines. They are also generally found with those devices and installations that automatically implement cleaning, heating, sintering, annealing, baking, boiling and drying processes. Due to its operating principle, process-dependent sequential control makes it possible to carry out certain program processing adjustments to accidental
irregularities during process events. They are found everywhere where there are no problems caused and in the controlled object where the occurrence of certain events (e.g., “target position reached”, “valve open”, “operating speed reached”) is recorded with suitable sensors and reported back to the control device. In everyday industrial practice,time and process dependent sequential control functions are combined in a multitude of ways.

Sequential control language
Graphical programming language according to IEC 1131-3 and DIN EN 61131-3 for structuring PLC application programs.

Servo Motors
Electric motors are used to drive mechanical components such as valves or to control or position mechanical axes for tool machines, robots and many other applications. To achieve small mechanical time constants, they have a small rotor torque and a large starting torque. They are available for all types of current (DC, AC, 3-phase), can be easily controlled and normally always function in periodic, intermittent or reversing operation.

Session layer
Layer 5 in the OSI reference model. This layer allows two applications on different devices to start use and end a session, i.e. a direct connection between the applications. It handles the dialog, regulates the length of data transfer and handles organization of which participant is sending or receiving as well as synchronization and restarting the session after an error.

SFC
Sequential Function Chart. Used for graphic representation of sequential control, graphic input language for

Signal
Physical value that changes over time, e.g. a voltage or current with a parameter [amplitude, frequency, phase position] that provides concrete information about changes to another physical value. The respective parameter is called an information parameter. For example, an electric tachometer measures the rotational speed of a mechanical shaft, i.e. it is indicated by the amplitude of the tachometer output voltage. In this case, the amplitude of
the output voltage is the information parameter providing information about the rotational speed of the machine shaft over time according to the signal definition. It is possible to differentiate between different basic signal types depending on the number of values, availability over time and the number of information parameters. Analog, binary and digital signals are most important for automation technology.

Slot PLC
PC insert card that has full PLC functionality. On the PC, it is coupled via a DPR with the process using a fieldbus connection. It is programmed externally or using the host PC.

Software
All programs including the respective documentation available for the operation of data processing systems, computer systems and computer-based devices of all types. Software is implemented on hardware as the nonphysical functional elements of a computer system. Using the term software when referring to computer programs was initiated in 1958 by mathematician John Tukey, Princeton University. Software can be grouped as system software and application software.

SRAM
Static Random Access Memory. A high-speed RAM semiconductor type that is mostly used in computers for cache memory. Using a backup battery, the contents of this memory can also be retained during a power failure.

SVGA
Super Video Graphics Array. Graphic standard with a resolution of at least 800x600 pixels and at least 256 colors.

Switch
Device, similar to a hub, that takes data packets received in a network and, unlike a hub, does not pass them on to all network nodes, instead only to the respective addressee. Unlike a hub, a switch provides targeted communication within a network that only takes place between sender and receiver. Other network nodes are not involved.

Symbol
From the point of view of linguistics, a symbol is a „thing“ [mark, indicator, etc.] that represents „something else“ [in the real or virtual world]. A „symbol“ has a defined relationship with the object being referenced, an „icon“ has a visual similarity with the object being referenced and an „index“ is a reference to a fact or conclusion. For technical terminology [i.e. DIN 44300], characters are symbols that represent certain information [letters, numbers, special characters, etc.].

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T

Task
Program unit, which is assigned a specific priority by the real-time operating system. It contains a complete process and can consist of several modules.

TCP/IP
Transmission Control Protocol/Internet Suit of Protocols. Network protocol, generally accepted standard for data exchange in heterogeneous networks. TCP/IP is used both in local networks for communication between various computer and also for LAN to WAN access.

Terminals
Terminals are used to connect or attach electrical conductors. Terminals can be arranged in a row and usually have two separate poles (connection points). Single or multi-pole terminals (terminal blocks) can be grouped as terminal strips.

TFT display
Thin Film Transistor display. Display technology for LCD monitors in which each pixel is controlled by a thin film transistor.

Three-phase supply
Three-wire system with L1, L2, L3 or four-wire system with L1, L2, L3, N. All phases are isolated from ground and all device housings are grounded.

Time constant
Technical systems, which have input/output behavior that can be defined by a first order differential equation with the form T(dy/dt) + y = x, react to a jump of input value x from 0 to X or from X to 0 with reference to output value y according to the function y = X(1-exp[-t/T]) or y = X• exp[-t/T]. These are exponential functions in which T represents a time value. This value is referred to as a time constant and is a characteristic for the speed of a transition. After the time t = T has passed; the output value y has increased to 63% of X (in the first case) or it has been reduced to 37% of X (in the second case). After t = [3... 5]T, the transition has been completed in both cases. Many technical procedure at least loosely follow exponential functions, therefore the term time constant is often used to characterize the timing of systems as described above.

Time to market
Time span from the development of a product until it is ready for the market. The duration of this time span is becoming more and more important for the success of a company because of shorter market, product and technology cycles.

Topology
Network architecture. Type of connection between the network components [stations, nodes]. Standard basic structures are star structure. [All stations are connected to a central node. All communication runs through this node. Direct communication between stations is not possible] Line structure [All stations are in a single common transfer path. Only one message can be transferred from one station to another at one time] Ring structure [All stations are connected in the form of a ring. There is no central node. All stations have the same rights] Mixed structure [Each station is connected to several others. Several independent transfer paths can exist between two stations. This redundancy can be used to guarantee data transport if a transfer path is broken] Tree structure [Branched topologies are created by combining the structures mentioned]. Depending on the existing conditions, most real applications have mixed structures. For industrial automation, for example, the
structure of the communication network used is heavily influenced by the special properties of the automation object [machine/system]. Applications for star network structures are mostly limited to small areas with many devices, such as individual production machines. Tree configurations, which group several star structures, are found in complex systems with many autonomous subsystems. Line structures are especially well suited for longer objects such as conveyor systems and ring structures are especially well suited for systems with stricter requirements on reliability.

Torque constant
The torque constant determines the torque created by the motor with 1 Arms phase current. This value applies at a motor temperature of 20° C. When the temperature increases, the torque constant is reduced (typically up to 10 %). When the current increases, the torque constant is reduced (generally starting at twice the value of the rated current).

Torque motors
Torque motors are rotating drive elements for direct drive technology. In modern designs, these are brushless synchronous motors with highly poled permanent magnet excitation in the internal or external rotor designs. However, they are also still available as DC motors with brushes. They are often used for the tooled machine industry as a replacement for hydraulic and standard electric drive structures made up of electric motors and a gear unit. They are set up for high torque [up to several 1,000 Newton meters, Nm] and low speeds and their mechanical concept makes them easy to integrate in the mechanisms and machines to be driven. This allows an extremely compact and efficient system construction that works with low oscillations, low play, low noise and is mostly wear and maintenance free and has improved machine dynamics, repeatability and positioning precision. The most important selection criteria for torque motors are maximum acceleration [Nm/kgm2] and the motor constant Km measured in Nm/W1/2. It determines the loss at a certain torque independent of the speed. Torque motors are used, for example, in rotary table and swivel axis drives on tool machines, as drives for extruders in the plastics industry, as cylinder drives for foil machines, as robot axis drives and in many other applications.

Touch screen
Screen with touch sensors for activating an item with the finger.

Transport layer
Layer 4 in the OSI reference model. This layer is responsible for correct data representation i.e. for error detection and error correction. It converts the flow of data being sent into small data packets and converts the data packets being received back to a flow of data. Send and receive confirmation are also part of this layer. The main tasks of this layer are opening and closing node connections and guaranteeing secure data transfer.

Turning moment motors (see torque motors)

TÜV
Technical monitoring organization www.tuevs.de

Twisted pair
Pair of copper wires twisted together. Transfer media for signals.

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U

UART
Universal Asynchronous Receiver/Transmitter

UDMA
Ultra Direct Memory Access. A special IDE data transfer mode that allows high data transfer rates for disk drives. There have been many variations in the recent times. UDMA33 mode transfers 33 megabytes per second. UDMA66 mode transfers 66 megabytes per second. UDMA100 mode transfers 100 megabytes per second.

UDP
User Datagram Protocol. Network protocol.

UPS
Uninterruptible Power Supply. UPS devices and systems are made up of switches, AC and DC inverters and especially batteries that provide a continuous supply of power to the user for a relatively long period of time during a power failure and, if necessary, can improve the current quality.

USB
Universal Serial Bus. Cost-effective serial interface for PCs; IBM standard supported by Intel, Compaq and Microsoft and other well-known companies; up to 127 peripheral devices [mouse, keyboard, printer, scanner, digital cameras, modems, CDROM drives, telephones, etc.] can be connected to a single USB port. The connected devices are also supplied with power via the 4-wire bus cable. The version on the market since 2001 (Version USB 2.0) allows data transfer rates up to 480 Mbps and is therefore also useful for transferring video data and for high-speed disk drives. www.usb.org

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V

VDE
The Association for Electrical, Electronic & Information Technologies (Verband der Elektrotechnik Elektronik Informationstechnik e.V.) www.vde.de

VGA
Video Graphics Adapter

W

Windows CE
Compact 32-bit operating system with multitasking and multithreading, that Microsoft developed especially for the OEM market. It can be ported for various processor types and has a high degree of real-time capability. The development environment uses proven, well established development tools. It is an open and scalable Windows operating system platform for many different devices. Examples of such devices are handheld PCs, digital wireless receivers, intelligent mobile phones, multimedia consoles, etc. In embedded systems, Windows CE is also an excellent choice for automation technology.

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X

XGA
eXtended Graphics Array. An extended standard for graphic controllers and displays that IBM introduced in 1990. This standard supports a 640 * 480 resolution with 65,536 colors or a 1024 * 768 resolution with 256 colors. This standard is generally used in workstation systems.

XML
eXtensible Markup Language. This new language was officially recommended in 1998 by the World Wide Web Consortium W3C as standard for web publishing and document management in client-server environments. Further development of the SGML standard. Unlike SGML documents, XML documents do not require a schema description in the form of a DTD. XML is already supported completely in the newer versions of many ERP und
MES systems. XML is accepted as an industrial standard thanks to its simple notation. Information is represented using the ASCII character set. This makes XML easy to read and transparent, and for the most part, portability of the text form is superior to binary structures. www.xml.com

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