3 Different Types of Electrical Wiring Diagrams Explained

An electrical wiring diagram with a pen pointing to a specific notation.
  • Intermediate

There are several different types of electrical wiring diagrams. They all do essentially the same thing, which is to show you how circuits are wired. However, the variation in these diagrams shows how circuits are mapped out in different ways to accomplish different ends. The type of electrical wiring diagram you use depends on what you want to achieve with it.


An electrical wiring diagram will use different symbols depending on the type, but the components remain the same. Diagrams will show receptacles, lighting, interconnecting wire routes, and electrical services within a home. This includes circuit breaker boxes and any alarms that are wired into the system. Different switches and different types of outlets all have different symbols, and you’ll need to know these symbols in order to be able to read an electrical wiring diagram.

Everything within a home electrical system will be shown on one of these diagrams. This is to make sure that everything will operate correctly if the diagram is adhered to and all components are functional.

1. Schematic Diagrams

Schematic electrical wiring diagrams are different from other electrical wiring diagrams because they show the flow through the circuit rather than the physical layout of any equipment. A schematic is best described as an impression of the circuit and wiring than a genuine representation. Schematics can be used for general information about the flow of the current as well as troubleshooting a circuit since they show wiring and components using specific symbols that actually show the function of equipment within the circuit; however, these symbols don’t look like the equipment itself.

The system flow is shown by a series of horizontal and vertical lines, much like a normal electrical wiring diagram. However, in this case, the lines show the flow of the system rather than the actual physical placement of the wires within the system. It’s an electrical wiring diagram that’s aimed more at designers and technicians who work with the theory of the circuit. Schematics will not be ideal for anyone who plans on working on the circuit as it is in the house.

2. Wiring Diagram

A wiring diagram is the most common form of the electrical wiring diagram. Unlike a schematic, it’s concerned with the connections between the different parts of a circuit or parts of an entire electrical system. Wiring and equipment on the wiring diagram are carefully laid out to show the approximate location of equipment in the circuit and thus, within the home. This makes it far more useful as a reference and guide for anyone wanting to work on a home’s electrical.

The components within the circuit are represented by a series of pictorials and these accurately resemble the components within the system so they can be easily identified. While the horizontal and vertical lines of a schematic show the circuit’s flow, lines in a wiring diagram instead represent the physical wiring of the circuit.

3. Pictorial

The least useful of the main electrical wiring diagrams is the pictorial diagram and for this reason alone, it’s not commonly used. It makes no attempt to be an accurate representation of the circuit but concentrates on the components in the circuit. Without precise knowledge, the average homeowner wouldn’t be able to use it effectively.