ERD Symbols and Meanings

Entity Relationship Diagram (ERD) is a popular software engineering tool for database modeling and illustration the logical structure of databases, which uses one of two notations - Chen's or Crow’s Foot. Crow's foot notation is effective when used in software engineering, information engineering, structured systems analysis and design. Each of these notations applies its own set of ERD symbols. Crow's foot diagrams use boxes to represent entities and lines between these boxes to show relationships. Varied shapes at the ends of lines depict the cardinality of a given relationship. Chen's ERD notation is more detailed way to represent entities and relationships. ConceptDraw DIAGRAM application enhanced with all-inclusive Entity-Relationship Diagram (ERD) solution allows design professional ER diagrams with Chen's or Crow’s Foot notation on your choice. It contains the full set of ready-to-use standardized ERD symbols and meanings helpful for quickly drawing, collection of predesigned ERD samples, examples and templates. ConceptDraw Pro is a great alternative to Visio for Mac users as it offers more features and can easily handle the most demanding professional needs.

How to Build an Entity Relationship Diagram (ERD)

Electrical Symbols, Electrical Diagram Symbols

When drawing Electrical Schematics, Electrical Circuit Diagrams, Power Systems Diagrams, Circuit and Wiring Diagrams, Digital and Analog Logic Schemes, you will obligatory need the electrical symbols and pictograms to represent various electrical and electronic devices, such as resistors, wires, transistors, inductors, batteries, switches, lamps, readouts, amplifiers, repeaters, relays, transmission paths, semiconductors, generators, and many more. Today these symbols are internationally standardized, so the diagrams designed using them are recognizable and comprehensible by specialists from different countries. Electrical Engineering Solution included to ConceptDraw Solution Park provides 26 libraries with 926 commonly used electrical schematic and electrical engineering symbols making the reality the easy drawing of Electrical diagrams, schematics and blueprints. Now you need only a few minutes to create great-looking Electrical diagram, simply choose required electrical design elements from the libraries, drag them on the needed places at the document and connect in a suitable way.

Mechanical Drawing Symbols

Mechanical Drawings are the special type of technical diagrams that visualize the structure of complex systems and illustrate the information about ventilation, heating, air conditioning, i.e. HVAC systems. These drawings are created on the base of floor plans and reflected ceiling plans, and then become an obligatory part of construction project which is needed directly for construction a building and for receiving a permit on it. Mechanical drawings and diagrams help effectively represent construction, technical and engineering solutions, and also schematics of different mechanical equipment. ConceptDraw DIAGRAM ector drawing software enhanced with Mechanical Engineering solution from Engineering area of ConceptDraw Solution Park provides wide set of effective drawing tools, predesigned mechanical drawing symbols, templates, samples and examples. Use of standardized and recognized mechanical vector symbols helps you design understandable mechanical drawings, diagrams and mechanical engineering schematics.

Electrical Symbols — Switches and Relays

In electrical engineering, a switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another. The mechanism of a switch may be operated directly by a human operator to control a circuit (for example, a light switch or a keyboard button), may be operated by a moving object such as a door-operated switch, or may be operated by some sensing element for pressure, temperature or flow. A relay is a switch that is operated by electricity. Switches are made to handle a wide range of voltages and currents; very large switches may be used to isolate high-voltage circuits in electrical substations. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Transformers and Windings

A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. Electromagnetic induction produces an electromotive force within a conductor which is exposed to time varying magnetic fields. Transformers are used to increase or decrease the alternating voltages in electric power applications. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Technical Drawing Software

Technical drawing or draft is a form of specialized graphic communication, exchange of ideas in industry and engineering. It is a visual representation of object with indication of dimensions and used material, constructed with maintaining the proportions between its parts. Technical drawings are constructed by architects, technologists, engineers, designers, drafters, and other technical professionals according to defined rules, specifications, internationally accepted standards and standardized notations allowing to make unambiguous, clear and understandable technical drawings. ConceptDraw DIAGRAM extended with Electrical Engineering solution, Mechanical Engineering solution, Chemical and Process Engineering solution from Industrial Engineering Area of ConceptDraw Solution Park is ideal technical drawing software. Its powerful drawing tools, predesigned vector objects, templates, samples are helpful for creation all kinds of Technical Drawings and Technical Diagrams, Electrical and Mechanical Schematics, Circuit and Wiring Diagrams, Structural Drawings, and many other.

Electrical Symbols — Semiconductor

Semiconductors are crystalline or amorphous solids with distinct electrical characteristics. They are of high resistance — higher than typical resistance materials, but still of much lower resistance than insulators. Their resistance decreases as their temperature increases, which is behavior opposite to that of a metal. Finally, their conducting properties may be altered in useful ways by the deliberate, controlled introduction of impurities into the crystal structure, which lowers its resistance but also permits the creation of semiconductor junctions between differently-doped regions of the extrinsic semiconductor crystal. The behavior of charge carriers which include electrons, ions and electron holes at these junctions is the basis of diodes, transistors and all modern electronics. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Inductors

An inductor, also called a coil or reactor, is a passive two-terminal electrical component which resists changes in electric current passing through it. It consists of a conductor such as a wire, usually wound into a coil. Energy is stored in a magnetic field in the coil as long as current flows. When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, according to Faraday’s law of electromagnetic induction. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Composite Assemblies

Electronic components have two or more electrical terminals (or leads) aside from antennas which may only have one terminal. These leads connect to create an electronic circuit with a particular function (for example an amplifier, radio receiver, or oscillator). Basic electronic components may be packaged discretely, as arrays or networks of like components, or integrated inside of packages such as semiconductor integrated circuits, hybrid integrated circuits, or thick film devices. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Lamps, Acoustics, Readouts

Wiring and circuit diagrams use special symbols recognized by everyone who uses the drawings. The symbols on the drawings show how components like resistors, capacitors, inductors, switches, lamps, acoustic devices, measuring devices and other electrical and electronic components are connected together. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Process Flow Diagram Symbols

Chemical and Process Engineering Solution from the Industrial Engineering Area of ConceptDraw Solution Park is a unique tool which contains variety of predesigned process flow diagram symbols for easy creating various Chemical and Process Flow Diagrams in ConceptDraw DIAGRAM.

Wiring Diagrams with ConceptDraw DIAGRAM

A Wiring Diagram is a comprehensive schematic that depicts the electrical circuit system, shows all the connectors, wiring, signal connections (buses), terminal boards between electrical or electronic components and devices of the circuit. Wiring Diagram illustrates how the components are connected electrically and identifies the wires by colour coding or wire numbers. These diagrams are necessary and obligatory for identifying and fixing faults of electrical or electronic circuits, and their elimination. For designing Wiring Diagrams are used the standardized symbols representing electrical components and devices. ConceptDraw Solution Park offers the Electrical Engineering solution from the Engineering area with 26 libraries of graphics design elements and electrical schematic symbols for easy drawing various Wiring Diagrams, Electrical Circuit and Wiring Blueprints, Electrical and Telecom schematics of any complexity, Electrical Engineering Diagrams, Power Systems Diagrams, Repair Diagrams, Maintenance Schemes, etc. in ConceptDraw DIAGRAM software.

Entity Relationship Diagram Symbols

The semantic modeling method nowadays is successfully applied in database structure design. It is effective method of modeling the data structures, which is based on the meaning of these data. As a tool of semantic modeling, there are used different types of Entity-Relationship Diagrams. Entity Relationship Diagram (ERD) is applied to visually and clearly represent a structure of a business database. The main components of ERDs are: entity, relation and attributes. An entity is a class of similar objects in the model, each entity is depicted in the form of rectangle and has the name expressed by a noun. Relation is shown in the form of non-directional line that connects two entities. There are several notation styles used for ERDs: information engineering style, Chen style, Bachman style, Martin Style. The Entity Relationship Diagram symbols used for professional ERD drawing are predesigned by professionals and collected in the libraries of the Entity-Relationship Diagram (ERD) solution for ConceptDraw DIAGRAM software.

Electrical Symbols — Qualifying

A qualifying symbol is graphics or text added to the basic outline of a device’s logic symbol to describe the physical or logical characteristics of the device. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Integrated Circuit

An integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small plate ("chip") of semiconductor material, normally silicon. This can be made much smaller than a discrete circuit made from independent electronic components. ICs can be made very compact, having up to several billion transistors and other electronic components in an area the size of a human fingernail. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Rotating Equipment

Electrical rotating machines, such as motors and generators, are vital assets for any power plant or large industrial company. An electric motor is an electrical machine that converts electrical energy into mechanical energy. The reverse of this would be the conversion of mechanical energy into electrical energy and is done by an electric generator. In normal motoring mode, most electric motors operate through the interaction between an electric motor's magnetic field and winding currents to generate force within the motor. In certain applications, such as in the transportation industry with traction motors, electric motors can operate in both motoring and generating or braking modes to also produce electrical energy from mechanical energy. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Electrical Symbols — Delay Elements

Variable delay elements are often used to manipulate the rising or falling edges of the clock or any other signal in integrated circuits. Delay elements are also used in delay locked loops and in defining a time reference for the movement of data within those systems. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.

Technical Drawing Software

In conditions of rapidly developing and progressing modern technologies in various fields of science and technics, a powerful specialized software is very popular and highly demanded today. In this area particularly valuable is a technical drawing software. ConceptDraw DIAGRAM is a unique professional vector diagramming software for business and technical drawing. Enhanced with powerful drawing tools of Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park, it is ideal for designing Technical Drawings, Electrical Schematics, Mechanical Systems Drawings, Plumbing Drawings, Structural Drawings, Architectural Drawings, Circuit Diagrams, and many other types of technical diagrams and schematics of any degree of complexity and any level of detailing. Included numerous predesigned mechanical engineering and technical drawing objects and symbols make a technical drawing process as simple as possible. Besides, ConceptDraw DIAGRAM offers extensive export capabilities that promote the active exchange of ideas and results with colleagues and other stakeholders.

Chemical Engineering

ConceptDraw DIAGRAM is a powerful diagramming and vector drawing software. Extended with Chemical and Process Engineering Solution from the Industrial Engineering Area of ConceptDraw Solution Park, it became the best Chemical Engineering software.