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Making communication easier

The basic role of  IEC Technical Committee 3: Information structures, documentation and graphical symbols is to help make communication of information among people (and computers) easier and more reliable. In particular, this means communication among customers, suppliers, engineers and maintenance people of information on products and systems.

Two broad categories are covered by TC 3: graphical symbols and the structuring of information.  These categories are further broken down into several areas of activity (structuring and identification, document and documentation management, current document kinds, graphical symbols for diagrams, graphical symbols for use on equipment, information modeling, semantical definitions and data element types).

Graphical symbols

A graphical presentation tells more than a thousand words. Therefore a basic task of TC 3 is to develop graphical symbols that convey information in a clearly understandable and, as far as possible, entirely language-independent way.

Most people understand the graphical symbol for an on/off switch or a fast-forward button. Graphical symbols are visual identifiers that are easy to understand. They're important because they make communicating an idea almost effortless, regardless of the language spoken and the country they're used in. No matter what their own mother tongue, anybody can easily learn to understand what the symbol means.

The IEC prepares symbols for use on equipment, as well as symbols for use in diagrams (the latter are mostly used by engineers for technical drawings). In doing so, it creates a universal language of graphical symbols that is useful to consumers and professionals all around the world.

Graphical symbols on equipment are for use where the meaning is to be understood by end-users of a product. Have a look at your kitchen appliances, or a radio or TV set. There you’ll find a lot of these symbols, such as the control buttons of your dishwasher.

Graphical symbols for diagarms are for use in electrotechnical documentation, intended for experts with the skills for interpreting them.

Structuring of information

The total amount of information dealt with in an engineering process for a product or system may be enormous. Therefore it is of crucial importance to bring order into it. Information is structured and by this reduced to individual elements that can be better handled. A series of standards developed by TC 3 covers this issue by providing rules for structuring of information and for designating objects and related documentation.

Of course, there also needs to be rules established for preparing electrotechnical documents, such as rules for how graphical symbols are to be used to present information. Such documents are known as circuit diagrams, function charts, connection diagrams, parts lists, instructions and so forth.

Today information technology (IS/IT) also governs the field of documentation and information interchange and so additional standards are needed.

Standardized information models describe the interrelation among different pieces of information.

The information pieces themselves, such as the properties of a product, also need to be standardized independent of terminology and language and unambiguously identified

The technical work of Technical Committee 3 (Information structures, documentation and graphical symbols) is partly taking place in the TC itself, partly in two subcommittees: SC 3C (Graphical symbols for use on equipment) and SC 3D (Libraries of component data).


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