Understanding Electrical Symbols

Electrical circuit diagram symbols may seem cryptic at first, but they are easily understandable, once you know what you’re looking at. With these basic graphic symbols in this guide, you can map out many electric circuit diagrams. Although, there are other advanced symbol categories, too.

Industry standard electrical component symbols are vital for sharing knowledge about applications of electric and electronic systems:

• Clarity: Electrical symbols allow electric engineers to clearly show electricians what they want wired, and how.
• Safety: A circuit diagram with clear electrical symbols can reveal safety hazards to those who know what to look for.
• Common Language: Electrical symbols transcend written languages, allowing electricians all over the world to understand each other’s work.
• Troubleshooting: When problems arise in electric circuits, the interconnection wiring diagram is provided for the first thing to look at. With clear, simple to understand electrical schematic symbols, electricians can quickly figure out what they’re looking at and begin diagnosing the problem.
• Business: By using standard electrical symbols for their industry components, merchants can clearly describe what they sell.

Electrical circuit symbols are simple graphics and follow a common logic, but they can be a lot to take in for the new user. Keep the following tips in mind when reading electrical schematic diagram symbols:

• Symbols joined with a dot indicate an electric connection between components.
• Plus and Minus symbols indicate a specific direction of charge (DC only).
• A backwards, rotated S-symbol (a wave symbol) indicates AC current.
• An arrow parallel to wire direction indicates current direction.
• A diagonal arrow superimposed on a symbol indicates adjustability.
• A single capital letter in a circle indicates an electrical properties measuring instrument.
• Triangles, as in diode symbols, point in the default current direction.

Electrical circuit symbols represent all the components involved in distributing electrical power. This includes powering motors, lights, heaters, and speakers. Making this happen involves wires, power sources, switches, relays, inductors, and grounding working together, and these all require detailed, accurate circuit diagrams to ensure the system works properly. 

What are the common electrical symbols used in industry? The sections below outline the most basic electrical components symbols.

As the connectors transmitting electric energy between all electric devices, wires are the most basic of electronic components. This wire symbol section also includes fuse symbols.

Source and cell symbols represent any device initiating electric discharge through a circuit, be that through controlled voltage or current.

An indispensable part of circuit safety, ground symbols depict a safe current termination.

Relay and switch symbols indicate devices that direct current.

Inductors are coils of wire that store electric energy in a magnetic field when current flows through them.

Electric motors and electromechanical devices convert electric energy into mechanical energy or sound, light, or heat energy.

With this beginner’s knowledge of electrical symbols, you can create circuit diagrams tailored to your application. Consider using computer-aided design (CAD) software programs with electrical symbols libraries to help quickly place symbols and map out circuits.

Graphic symbols only describe the function of each part, though. These various components interact with each other differently (though in predictable ways) depending on the electrical circuit. Always ensure trained professionals review any drafted schematics before wiring anything.

RS has product lines covering all these categories of electric and electronic parts. Browse them today to plan your circuits.