Electrical symbols are a graphical representation of basic electrical and electronic devices or components. These Symbols are used in circuits and electrical diagrams to recognize a component. It is also called a schematic symbol. Each component has typical functionality according to its operational characteristics.
An electronic circuit or schematic drawing uses a wired path between electronic components to complete the circuit. These components are represented by respective symbols for it.
Electrical and electronic symbols used in circuits are defined by various national and international standards. E.g. IEC standard, JIC standard, ANSI standard, IEEE standard, etc.
Though electrical symbols are standardized, they may vary from country to country, or engineering disciplines, based on traditional conventions.
This enables anyone to read electrical circuits or Electrical schematic diagrams and floor plans with ease and clarity.
Electrical symbols represent the components of electrical and electronic circuits and do not define any function or process unless the circuit is implemented with components being physically used. (E.g. the circuit on a breadboard or assembled printed circuit board)
There is a circuit symbol for each and every electrical component or device used in a circuit such as passive components, active components, measuring instruments, logic gates, etc.
A few electronic symbols that can be used in the circuit diagrams are given below for reference:
Not Connected wires
Iron Core Inductor
Definition of an Inductor: It is a device that temporarily stores energy in the form of a magnetic field. You can learn more about the Basics of Inductors.
Lamp/Light Bulb Symbols
Switch and Relay Symbols
SPST Toggle Switch
SPDT Toggle Switch
Pushbutton Switch (N.C)
Pushbutton Switch (N.O)
SPST Relay/SPDT Relay
Definition of a Relay: It controls circuits by opening and closing contacts in another circuit. Relays switches are used to open and close circuits electromechanically or electronically.
Resistor (IEEE)/ Resistor (IEC)
Variable Resistor / Rheostat (IEEE)/(IEC)
Photoresistor / Light-dependent resistor (LDR)
Definition of a Resistor: As the name suggests, they resist the flow of excessive electrical power or voltage passing through the circuit, in a precise and controlled manner. Check the basics of Resistor.
Definition of a Capacitor: It is a device that stores electrical energy in an electric field. It is a passive electronic component. check the basics of capacitors.
Antenna / aerial
Antenna / aerial
Definition of an Antenna: An electrical device converts electric power into radio waves and vice versa. You can learn more about Antenna and their basics.
Power Supply Symbols
Voltage Source/ Current Source
Battery Cell/ Battery
Controlled voltage source/Controlled Current source
AC voltage source/Generator
Tunnel Diode/Light Emitting Diode
Schottky Diode/Varicap Diode
Definition of a LED: It is a semiconductor device that emits light when an electric current is passed through it. Learn more about LED here.
NPN Bipolar Transistor/ PNP Bipolar Transistor
JFET-N Transistor/ JFET-P Transistor
Definition of a Transistor: It is a semiconductor device used to amplify or switch electronic signals and electrical power. Check the basics of transistors.
Microphone / Loudspeaker
Op-amp /Schmitt trigger
Analog-to-Digital Converter (ADC)
Digital-to-Analog Converter (DAC)
Logic Gate Symbols
AND /NAND Gate
XOR Gate / NOT Gate
OR /NOR Gate
D flip flop /Multiplexer(MUX) 2 to 1
To read other interesting Electronics basics: click here
This article was first published on 18 April 2020 and was updated on 9 February 2021.