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PLCopen
PLCopen is an independent organisation providing efficiency in industrial automation based on the needs of users. PLCopen members have concentrated on technical specifications around IEC 61131-3, creating specifications and implementations in order to reduce cost in industrial engineering. The outcome for example is standardized libraries for different application fields, harmonized language conformity levels and engineering interfaces for exchange. Experts of the PLCopen members are organized in technical committees and together with end users define such open standards. PLCopen was founded in 1992 just after the world wide programming standard IEC 61131-3 was published. The controls market at that time was a very heterogeneous market with different types of programming methods for many different PLCs. The IEC 61131-3 is a standard defining the programming languages for PLCs, embedded controls, and industrial PCs, harmonizing applications independent from specific dialects, but sti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEC 61131-3
IEC 61131-3 is the third part (of 10) of the open international standard IEC 61131 for programmable logic controllers. It was first published in December 1993 by the IEC; the current (third) edition was published in February 2013. Part 3 of ''IEC 61131'' deals with basic software architecture and programming languages of the control program within PLC. It defines three graphical and two textual programming language standards: * Ladder diagram (LD), graphical * Function block diagram (FBD), graphical * Structured text (ST), textual * Instruction list (IL), textual (deprecated in 3rd edition of the standard) * Sequential function chart (SFC), has elements to organize programs for sequential and parallel control processing, graphical. Data types * Elementary Data Type ** Bit Strings – groups of on/off values *** BOOL - 1 bit (0,1) *** BYTE – 8 bit (1 byte) *** WORD – 16 bit (2 byte) *** DWORD – 32 bit (4 byte) *** LWORD – 64 bit (8 byte) ** INTEGER – whole numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instruction List
Instruction list (IL) is one of the 5 languages supported by the initial versions of IEC 61131-3 standard, and subsequently deprecated in the third edition. It is designed for programmable logic controllers (PLCs). It is a low level language and resembles assembly. All of the languages share IEC61131 Common Elements. The variables and function call are defined by the common elements so different languages can be used in the same program. Program control (control flow) is achieved by ''jump'' instructions and function calls (subroutines with optional parameters). The file format has now been standardized to XML by PLCopen. Example Variations from IEC 61131 Many vendors whilst incorporating the full IEC 61131-3 requirements have additional vendor specific calls/function blocks to suit their hardware such as reading or writing to I/O. Siemens PLC instruction list language is known as "Statement List" or "STL" in English, and "Anweisungs-Liste" or "AWL" in German, Italian and S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AutomationML
{{short description, Neutral data format AutomationML (Automation Markup Language) is a neutral data format based on XML for the storage and exchange of plant engineering information, which is provided as an open standard. The goal of AutomationML is to interconnect the heterogeneous tool landscape of modern engineering tools in their different disciplines, e.g. mechanical plant engineering, electrical design, HMI development, PLC and robot control. Approach AutomationML describes real plant components as objects encapsulating different aspects. An object can consist out of other sub-objects, and can itself be part of a bigger composition. It can describe a screw, a claw, a robot or a complete manufacturing cell in different levels of detail. Typical objects in plant automation comprise information about topology, geometry, kinematics and logic, where logic comprises sequencing, behaviour and control. AutomationML incorporates different standards through strongly typed links ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programmable Logic Controllers
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity that requires high reliability, ease of programming, and process fault diagnosis. Dick Morley is considered as the father of PLC as he had invented the first PLC, the Modicon 084, for General Motors in 1968. PLCs can range from small modular devices with tens of inputs and outputs (I/O), in a housing integral with the processor, to large rack-mounted modular devices with thousands of I/O, and which are often networked to other PLC and SCADA systems. They can be designed for many arrangements of digital and analog I/O, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed-up or non-volatile memory. PLCs were first de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structured Text
Structured text, abbreviated as ST or STX, is one of the five languages supported by the IEC 61131-3 standard, designed for programmable logic controllers (PLCs). It is a high level language that is block structured and syntactically resembles Pascal, on which it is based. All of the languages share IEC61131 Common Elements IEC 61131-3 is the third part (of 10) of the open international standard IEC 61131 for programmable logic controllers. It was first published in December 1993 by the IEC; the current (third) edition was published in February 2013. Part 3 of ''IEC .... The variables and function calls are defined by the common elements so different languages within the IEC 61131-3 standard can be used in the same program. Complex statements and nested instructions are supported: * Iteration loops (REPEAT-UNTIL; WHILE-DO) * Conditional execution (IF-THEN-ELSE; CASE) * Functions (SQRT(), SIN()) Sample program (* simple state machine *) TxtState := STATES tateMachine CAS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Function Block Diagram
The Function Block Diagram (FBD) is a graphical language for programmable logic controller design, that can describe the function between input variables and output variables. A function is described as a set of elementary blocks. Input and output variables are connected to blocks by connection lines. Inputs and outputs of the blocks are wired together with connection lines or links. Single lines may be used to connect two logical points of the diagram: * An input variable and an input of a block * An output of a block and an input of another block * An output of a block and an output variable The connection is oriented, meaning that the line carries associated data from the left end to the right end. The left and right ends of the connection line must be of the same type. Multiple right connection, also called divergence, can be used to broadcast information from its left end to each of its right ends. All ends of the connection must be of the same type. Function Block Dia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ladder Logic
Ladder logic was originally a written method to document the design and construction of relay racks as used in manufacturing and process control. Each device in the relay rack would be represented by a symbol on the ladder diagram with connections between those devices shown. In addition, other items external to the relay rack such as pumps, heaters, and so forth would also be shown on the ladder diagram. Ladder logic has evolved into a programming language that represents a program by a graphical diagram based on the circuit diagrams of relay logic hardware. Ladder logic is used to develop software for programmable logic controllers (PLCs) used in industrial control applications. The name is based on the observation that programs in this language resemble ladders, with two vertical rails and a series of horizontal rungs between them. While ladder diagrams were once the only available notation for recording programmable controller programs, today other forms are standardized in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequential Function Chart
Sequential function chart (SFC) is a visual programming language used for programmable logic controllers (PLCs). It is one of the five languages defined by IEC 61131-3 standard. The SFC standard is defined as ''Preparation of function charts for control systems'', and was based on (itself based on binary Petri nets). It can be used to program processes that can be split into steps. Main components of SFC are: * Steps with associated actions; * Transitions with associated logic conditions; * Directed links between steps and transitions. Steps in an SFC diagram can be active or inactive. Actions are only executed for active steps. A step can be active for one of two motives: * It is an initial step as specified by the programmer. * It was activated during a scan cycle and not deactivated since. Steps are activated when all steps above it are active and the connecting transition is superable (i.e. its associated condition is true). When a transition is passed, all steps above are d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OPC Foundation
The OPC Foundation (Open Platform Communications, formerly Object Linking and Embedding for Process Control) is an industry consortium that creates and maintains standards for open connectivity of industrial automation devices and systems, such as industrial control systems and process control generally. The OPC standards specify the communication of industrial process data, alarms and events, historical data and batch process data between sensors, instruments, controllers, software systems, and notification devices. The OPC Foundation started in 1994, as a task force comprising five industrial automation vendors ( Fisher-Rosemount, Rockwell Software, Opto 22, Intellution, and Intuitive Technology), with the purpose of creating a basic OLE for Process Control specification. OLE is a technology developed by Microsoft Corporation for the MS Windows operating system. The task force released the OPC standard in August 1996. The OPC Foundation was chartered to continue developme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OPC Unified Architecture
OPC Unified Architecture (OPC UA) is a cross-platform, open-source, IEC62541 standard for data exchange from sensors to cloud applications developed by the OPC Foundation. Distinguishing characteristics are: * Standardized data models freely available for over 60 types of industrial equipment, published by the OPC Foundation via Companion Specifications * Extensible security profiles, including authentication, authorization, encryption and checksums * Extensible security key management, including X.509, token and password * Support for both client-server and publish-subscribe communication patterns * Communication protocol independent. Mappings to several communication protocols like TCP/IP, UDP/IP, WebSockets, AMQP and MQTT are specified * Initially successful in standardized data exchange with industrial equipment (discrete manufacturing, process manufacturing, energy) and systems for data collection and control, but now also leveraged in building automation, weighing and kitc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Automation
Automation describes a wide range of technologies that reduce human intervention in processes, namely by predetermining decision criteria, subprocess relationships, and related actions, as well as embodying those predeterminations in machines. Automation has been achieved by various means including mechanical, hydraulic, pneumatic, electrical, electronic devices, and computers, usually in combination. Complicated systems, such as modern factories, airplanes, and ships typically use combinations of all of these techniques. The benefit of automation includes labor savings, reducing waste, savings in electricity costs, savings in material costs, and improvements to quality, accuracy, and precision. Automation includes the use of various equipment and control systems such as machinery, processes in factories, boilers, and heat-treating ovens, switching on telephone networks, steering, and stabilization of ships, aircraft, and other applications and vehicles with reduced human in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
