What Is a Schematic Diagram?

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A schematic is defined as a picture that shows something in a simple way, using symbols. A schematic diagram is a picture that represents the components of a process, device, or other object using abstract, often standardized symbols and lines. Schematic diagrams only depict the significant components of a system, though some details in the diagram may also be exaggerated or introduced to facilitate the understanding of the system.

Schematic diagrams do not include details that are not necessary for comprehending the information that the diagram was intended to convey. For example, in a schematic diagram depicting an electrical circuit, you can see how the wires and components are connected together, but not photographs of the circuit itself.

Key Takeaways: Schematic Diagram

  • A schematic diagram is a picture that represents the components of a process, device, or other object using abstract, often standardized symbols and lines.
  • Although schematic diagrams are commonly associated with electrical circuits, many examples can be found in other industries.

Schematic diagrams can also differ in their level of abstraction. Although they are typically composed of only abstract symbols and lines, some diagrams can also be semi-schematic and contain more realistic elements. Some diagrams can also contain words, such as when a process contains multiple elements that have not been standardized.

More simply, a schematic diagram is a simplified drawing that uses symbols and lines to convey important information. For example, if you are taking the subway you may see a “map” showing you all the stations along a subway line, but that map will not show all the roads and buildings you may pass along the way. In this case, the entire subway system can be represented as differently colored lines depicting the different subway routes, with dots indicating the stops along the lines.

An example of a public transportation map, using differnetly colored lines to represent the diffrent lines and dots to represent the stations along each line. Yuri_Arcurs / Getty Images.

Though schematic diagrams are most commonly associated with electronics, you have probably encountered many such diagrams, like the subway example above, even if you have never had to wire a circuit. Here are some examples of the many schematic diagrams you may encounter in your work or in your studies.

Examples of Schematic Diagrams

Schematic Diagrams in Electronics

A circuit diagram behind a circuit board. kr7ysztof / Getty Images.

Schematic diagrams are typically associated with electrical circuits. Also called wiring diagrams or circuit diagrams, these diagrams show how the different components of a circuit are connected. In these diagrams, lines represent connecting wires, while other elements like resistors, lamps, and switches are represented by standardized symbols called electrical schematic symbols.

In electronics, having a schematic diagram on hand may help a user design an entire circuit before building it, or troubleshoot an electronic that has stopped working.

Schematic diagrams may also be used to explain the general way that an electronic functions without detailing the hardware or software used in the actual electronic. For example, to explain how a computer projects the words you type on a screen, you might use a schematic diagram that shows how information passes from the keys you press to a word processing program, and finally to the computer screen.

Schematic Diagrams in Manufacturing

Schematic diagrams of various parts. Eakachai Leesin / EyeEm / Getty Images.

Schematic diagrams can be used to depict machines as well. For example, in a textbook a car engine may be depicted as a set of shapes that show how the different parts are positioned relative to one another. A schematic drawing may also be created by an engineer while they are designing the machine so that they can properly understand how the parts work together, and make any necessary changes before building the actual system.

Schematic Diagrams in Chemistry

Chemistry blackboard
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Many chemical products are often obtained by performing several different reactions at different steps of the process. A schematic diagram in chemistry can help someone understand all the reactions that were performed to yield a final product, without showing the actual products themselves. This may be portrayed, for example, as a series of boxes connected together with arrows, with words depicting the various elements and conditions that were used throughout the process.

Like for machines, a schematic diagram may also be used to depict the apparatus that was used for performing the reactions, especially if it is not typically used for reactions, or had been modified from an instrument that was already known.

Schematic Diagrams in Business

A flowchart that could be used to depict a business process. Sean Gladwell / Getty Images.

Schematic diagrams are helpful in conveying the main parts of a complicated business model and showing how they all relate together. For example, a marketing plan might consist of many different elements, such as strategy, objectives, and an action plan. A schematic diagram would then be used to help organize all those elements, including elements within each category, in ways that would convey the main ideas in a clear and concise fashion.