Electronic symbol
An electronic symbol is a pictogram used to represent various electrical and electronic devices (such as wires, batteries, resistors, and transistors) in a schematic diagram of an electrical or electronic circuit. These symbols can (because of remaining traditions) vary from country to country, but are today to a large extent internationally standardized. Some symbols represent components (such as vacuum tubes) which ceased to be used routinely as newer technologies were introduced.
There are several national and international standards for graphical symbols in circuit diagrams, in particular:
Different symbols may be used depending on the discipline using the drawing. For example, lighting and power symbols used as part of architectural drawings may be different from symbols for devices used in electronics. National and local variations to international standards also exist.
Symbols shown are typical examples, not a complete list.
(a) American-style resistor, (b) rheostat (variable resistor), and (c) potentiometer
(a) IEC-style resistor, (b) rheostat (variable resistor), and (c) potentiometer
Capacitor, polarized (American)
IEC-style adjustable capacitors
Inductor with magnetic core (IEEE Std 315)
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