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Electrical System Design
Electrical system design is the design of electrical systems. This can be as simple as a flashlight cell connected through two wires to a light bulb or as involved as the Space Shuttle. Electrical systems are groups of electrical components connected to carry out some operation. Often the systems are combined with other systems. They might be subsystems of larger systems and have subsystems of their own. For example, a subway rapid transit electrical system is composed of the wayside electrical power supply, wayside control system, and the electrical systems of each transit car. Each transit car’s electrical system is a subsystem of the subway system. Inside of each transit car there are also subsystems, such as the car climate control system. Design The following would be appropriate for the design of a moderate to large electrical system. # A specification document is written. It probably would have been written by the customer. The specification document states in plain l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electricity
Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Various common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others. The presence of an electric charge, which can be either positive or negative, produces an electric field. The movement of electric charges is an electric current and produces a magnetic field. When a charge is placed in a location with a non-zero electric field, a force will act on it. The magnitude of this force is given by Coulomb's law. If the charge moves, the electric field would be doing work on the electric charge. Thus we can speak of electric potential at a certain point in space, which is equal to the work done by an external agent in carrying a unit of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
One-line Diagram
In power engineering, a single-line diagram (SLD), also sometimes called one-line diagram, is a simplest symbolic representation of an electric power system. A single line in the diagram typically corresponds to more than one physical conductor: in a direct current system the line includes the supply and return paths, in a three-phase system the line represents all three phases (the conductors are both supply and return due to the nature of the alternating current circuits). The one-line diagram has its largest application in power flow studies. Electrical elements such as circuit breakers, transformers, capacitors, bus bars, and conductors are shown by standardized schematic symbols. Instead of representing each of three phases with a separate line or terminal, only one conductor is represented. It is a form of block diagram graphically depicting the paths for power flow between entities of the system. Elements on the diagram do not represent the physical size or location ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technical Communication
Technical communication is used to convey scientific, engineering, or other technical information. Individuals in a variety of contexts and with varied professional credentials engage in technical communication. Some individuals are designated as technical communicators or technical writers. These individuals use a set of methods to research, document, and present technical processes or products. Technical communicators may put the information they capture into paper documents, web pages, computer-based training, digitally stored text, audio, video, and other media. The Society for Technical Communication defines the field as any form of communication that focuses on technical or specialized topics, communicates specifically by using technology, or provides instructions on how to do something.What is Technical Communicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systems Engineering
Systems engineering is an interdisciplinary field of engineering and engineering management that focuses on how to design, integrate, and manage complex systems over their enterprise life cycle, life cycles. At its core, systems engineering utilizes systems thinking principles to organize this body of knowledge. The individual outcome of such efforts, an engineered system, can be defined as a combination of components that work in synergy to collectively perform a useful Function (engineering), function. Issues such as requirements engineering, reliability, logistics, coordination of different teams, testing and evaluation, maintainability and many other Discipline (academia), disciplines necessary for successful system design, development, implementation, and ultimate decommission become more difficult when dealing with large or complex projects. Systems engineering deals with work-processes, optimization methods, and risk management tools in such projects. It overlaps technical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the latter half of the 19th century after commercialization of the electric telegraph, the telephone, and electrical power generation, distribution, and use. Electrical engineering is now divided into a wide range of different fields, including computer engineering, systems engineering, power engineering, telecommunications, radio-frequency engineering, signal processing, instrumentation, photovoltaic cells, electronics, and optics and photonics. Many of these disciplines overlap with other engineering branches, spanning a huge number of specializations including hardware engineering, power electronics, electromagnetics and waves, microwave engineering, nanotechnology, electrochemistry, renewable energies, mechatronics/control, and electrical m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spreadsheet
A spreadsheet is a computer application for computation, organization, analysis and storage of data in tabular form. Spreadsheets were developed as computerized analogs of paper accounting worksheets. The program operates on data entered in cells of a table. Each cell may contain either numeric or text data, or the results of formulas that automatically calculate and display a value based on the contents of other cells. The term ''spreadsheet'' may also refer to one such electronic document. Spreadsheet users can adjust any stored value and observe the effects on calculated values. This makes the spreadsheet useful for "what-if" analysis since many cases can be rapidly investigated without manual recalculation. Modern spreadsheet software can have multiple interacting sheets and can display data either as text and numerals or in graphical form. Besides performing basic arithmetic and mathematical functions, modern spreadsheets provide built-in functions for common financial a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Harness
A cable harness, also known as a wire harness, wiring harness, cable assembly, wiring assembly or wiring loom, is an assembly of electrical cables or wires which transmit signals or electrical power. The cables are bound together by a durable material such as rubber, vinyl, electrical tape, conduit, a weave of extruded string, or a combination thereof. Commonly used in automobiles, as well as construction machinery, cable harnesses provide several advantages over loose wires and cables. For example, many aircraft, automobiles and spacecraft contain many masses of wires which would stretch over several kilometers if fully extended. By binding the many wires and cables into a cable harness, the wires and cables can be better secured against the adverse effects of vibrations, abrasions, and moisture. By constricting the wires into a non-flexing bundle, usage of space is optimized, and the risk of a short is decreased. Since the installer has only one harness to install (as opposed to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wiring Diagram
A wiring diagram is a simplified conventional pictorial representation of an electrical circuit. It shows the components of the circuit as simplified shapes, and the power and signal connections between the devices. A wiring diagram usually gives information about the relative position and arrangement of devices and terminals on the devices, to help in building or servicing the device. This is unlike a schematic diagram, where the arrangement of the components' interconnections on the diagram usually does not correspond to the components' physical locations in the finished device. A pictorial diagram would show more detail of the physical appearance, whereas a wiring diagram uses a more symbolic notation to emphasize interconnections over physical appearance. A wiring diagram is often used to troubleshoot problems and to make sure that all the connections have been made and that everything is present. Architectural wiring diagrams Architectural wiring diagrams show the app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circuit Nodes
In electrical engineering, a node is any region on a circuit between two circuit elements. In circuit diagrams, connections are ideal wires with zero resistance, so a node consists of the entire section of wire between elements, not just a single point. According to Ohm's law, ''V = IR'', the voltage across any two points of a node with negligible resistance is :V = IR = I\cdot 0 = 0, showing that the electric potential at every point of a node is the same. There are some notable exceptions where the voltage difference is large enough to become significant: * High-precision resistance measurements using a Kelvin connection * The difference in voltage between ground and neutral, between the neutral wire and the ground in domestic AC power plugs and sockets, can be fatal. A properly installed electrical system connects them together at only one location, leading many people to the fatally incorrect conclusion that they are at "the same" voltage, or that the safety ground i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schematic
A schematic, or schematic diagram, is a designed representation of the elements of a system using abstract, graphic symbols rather than realistic pictures. A schematic usually omits all details that are not relevant to the key information the schematic is intended to convey, and may include oversimplified elements in order to make this essential meaning easier to grasp, as well as additional organization of the information. For example, a subway map intended for passengers may represent a subway station with a dot. The dot is not intended to resemble the actual station at all but aims to give the viewer information without unnecessary visual clutter. A schematic diagram of a chemical process uses symbols in place of detailed representations of the vessels, piping, valves, pumps, and other equipment that compose the system, thus emphasizing the functions of the individual elements and the interconnections among them and suppresses their physical details. In an electronic circuit d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systems
A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purpose and expressed in its functioning. Systems are the subjects of study of systems theory and other systems sciences. Systems have several common properties and characteristics, including structure, function(s), behavior and interconnectivity. Etymology The term ''system'' comes from the Latin word ''systēma'', in turn from Greek ''systēma'': "whole concept made of several parts or members, system", literary "composition"."σύστημα" Henry George Liddell, Robert Scott, '' |
Functional Flow Block Diagram
A functional flow block diagram (FFBD) is a multi-tier, time-sequenced, step-by-step flow diagram of a system’s functional flow. The term "functional" in this context is different from its use in functional programming or in mathematics, where pairing "functional" with "flow" would be ambiguous. Here, "functional flow" pertains to the sequencing of operations, with "flow" arrows expressing dependence on the success of prior operations. FFBDs may also express input and output data dependencies between functional blocks, as shown in figures below, but FFBDs primarily focus on sequencing. The FFBD notation was developed in the 1950s, and is widely used in classical systems engineering. FFBDs are one of the classic business process modeling methodologies, along with flow charts, data flow diagrams, control flow diagrams, Gantt charts, PERT diagrams, and IDEF.Thomas Dufresne & James Martin (2003)"Process Modeling for E-Business". INFS 770 Methods for Information Systems Engineering: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
