Wires, power supplies, resistors, capacitors, diodes, transistors, meters, switches, sensors, logic gates, audio devices, and other components are commonly represented by electronic circuit symbols. A skilled technician can read these symbols to identify each component on a circuit board or panel.
Wiring diagrams are used to show the connections between wires as well as the physical location of various parts of the wiring system. Physical wiring systems use drawings called "floor plans" to show the placement of outlets, light switches, and other fixtures. Wiring diagrams are also used by electricians when repairing existing wiring systems. They test individual wires to determine their function before replacing them with new cable.
The actual process of creating a wiring diagram involves several steps. First, the electrician will measure the length of wire needed to connect two points together. Next, he or she will select the appropriate size wire for the job. Then, depending on the type of connection required, the electrician will either cut the wire in half or tie two pieces of wire together with a splice. Each section of wire will be labeled with tape to indicate its purpose. Last, the electrician will connect all the sections of wire to each other using proper connectors. If any part of the wiring system is old or damaged, the electrician will include notes about the change on the final wiring diagram.
In circuit diagrams, these electrical and electronic circuit symbols are used to show how a circuit is linked. Electronic circuit symbols are signs, drawings, or pictograms of various components used to represent electronic components in an electronic circuit's schematic layout. The first electronic circuit schematics were made by hand using pen and paper, but now computer-aided design (CAD) software is commonly used.
Current is the flow of electrons through a conductor such as a copper wire. Electric circuits contain many different elements that require some form of power source to operate. For example, light bulbs use current to create heat which produces light. Power sources can be either internal or external to the device requiring current. Internal power sources include batteries while external power sources include outlets on house wires or electricity generators driven by engines or turbines. Current flows from the power source through the conductors of the circuit to each component being supplied with power. The direction of current flow is important because it indicates whether a component is acting as a source or a sink of current. For example, if LED lights are connected in reverse bias then they will act as sinks for current rather than sources. This is important when considering how to safely connect components in a circuit.
Electronic components have terminals called pins or pads that input and output signals and power into and out of the component.
The most widely used symbols in circuit diagramming are electrical symbols. These symbols are used to identify electrical components such as resistors, capacitors, inductors, and wires that conduct electricity. Electrical symbols are used in schematic diagrams created by electricians, technicians, and engineers.
Also used are mechanical symbols which represent physical parts such as valves or motors. These are usually drawn with solid lines and labeled with the word "mechanical". Mechanical drawings are used by plumbers, carpenters, and other skilled labor forces who need to know what parts of a building are not electrified.
Electrical and mechanical drawings can be combined on one sheet if necessary. For example, a motor may require some wiring to operate it, so both an electrical symbol and a mechanical symbol would need to be included on the same page.
Other symbols used in circuit diagrams include reference symbols which are used again and again in different locations on a single circuit diagram or across multiple circuit diagrams. For example, a voltage source might be needed at many different points on a circuit for various reasons, so it makes sense to include it only once and refer to it later via a reference symbol.
In circuit diagrams, circuit symbols are used to depict how a circuit is joined together. The real component configuration is generally somewhat different from the circuit schematic. The difference is due to the limitations of space on the printed circuit board (PCB) as well as the need for physical separation between components.
The actual process of joining circuits together uses connections called "traces". A trace is a copper pathway on the PCB that connects the electrodes of one component or group of components with those of another. Each component has several electrodes, and these are usually marked with small circles called "pads". The traces connect pads on one component with corresponding pads on another component or group of components. Traces can be routed anywhere on the PCB that space allows; however they usually follow the boundary lines between components to prevent current from leaking into or out of certain areas. A single electrode can be connected to multiple traces at different times during assembly of the circuit. This is known as "multiple-trace routing", and it provides flexibility in the design phase of a project.
The term "circuit symbol" is also used to describe any picture or drawing used to explain the behavior of an electrical circuit.
Basic electrical and electronic graphical symbols known as "schematic symbols" are often used to designate the position of different components and elements inside a circuit in circuit diagrams, schematics, and computer-aided drawing programs. The term "electrical schematic" is also used for such drawings.
Electrical schematics contain information about the relative positions of electrical components which are needed to correctly connect up or operate various devices using electricity. Electrical schematics show the position of wires, cables, terminals, pins, posts, pads, etc., that make up an electrical system. They indicate the direction in which to insert connectors and labels to identify parts of the circuit.
A schematic can be created manually using a pencil and paper or using computer software. When creating a schematic manually, the artist will first draw the physical layout of the circuit on a piece of paper. Then, they will use their knowledge of the circuit's components to mark where each wire goes. Next, they will identify the need for each leg of each component by labeling each conductor with a symbol or letter indicating its purpose. For example, if there were three wires coming out of a single power source, they would be labeled W, X, and Y. Each label then represents one side of a current-carrying device such as a resistor or capacitor.