In electronics, an electrical schematic is a graphical drawing of an electric circuit in which symbols are used to represent electrical objects like batteries, inductors and resistors. Reading an electrical schematic requires that a person know what all the objects and their symbols represent. A partial list of objects found on a schematic are diodes, switches, wires, power supply sources, capacitors, transistors and logic gates.
For each one of these devices that may be on a circuit diagram, there are corresponding symbols. For example, a conductor or electrical wire can be drawn as a horizontal line on this schematic. If this electric wire is connected, then a dot is placed on the horizontal line and a vertical line is added. Similarly, a switch can be used to disconnect the current if it is in the open position on a diagram. There are many different types of switches, including single and multiple pole switches. The symbol use for switches can be the letter S. Some other symbols used on an electrical diagram are R for resistors, C for capacitors, L for inductors and Q for transistors.
Power sources are represented by a circle and the letter designation of DC or AC as the voltage type. The DC voltage symbol has a plus and minus signs inside the circle. There are many other symbols and ways to draw the different devices, such as meters and oscillators, used in these schematics. Reading electrical schematics involves knowing about electronic subjects, such as junctions, nodes and labels used for net names.