Help for Understanding Simple Home Electrical Wiring Diagrams

Help for Understanding Simple Home Electrical Wiring Diagrams
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Fundamentals of Household Wiring

Are you planning to move into a new house and feel pretty excited about doing some innovative electrical wiring there all by yourself? The idea sounds great as that gives you the freedom to customize the design for home wiring layout, and also help in saving quite a lot of money. But this is not possible before you are well versed with the basics of electrical wiring and know exactly how to chalk out correct home electrical wiring diagrams.

In this article we will get acquainted with the various general electrical components, their symbols and also study the different fundamental electrical wiring configurations normally involved in every domestic the wiring. But before that, let’s briefly look at what electricity is.

What is Electricity?

Electricity: The power that we receive in our houses from power stations in the form of alternating current and voltage is in fact the electricity. Any electrical wiring is useless without electricity and thus it becomes the life line of all electrical systems. Generally, these are either around 110 or 220 volts depending upon which part of the globe you are in. Similarly its frequency will be approximately 60 and 50 Hertz respectively. Its Main Line is termed as the Phase or Live while the other receiving terminal is called the Neutral. It can be absolutely FATAL to touch the Phase terminal whereas the Neutral is just the opposite and won’t produce any effect.

Do Not Try to Experiment

Important Electrical Components


The SPST Switch: It is the most basic and useful part of any electrical wiring. A switch is a mechanical spring loaded device used to manually make or break the supply or the power (Always the Phase) to the connected load so that it can be activated or deactivated at will. SPST stands for Single Pole Single Throw as these are able to connect or disconnect only a single supply line (Refer symbol).

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A Typical Switch and 3-Pin Socket, Image

The Socket: These can be seen in the form of AC MAINS power outlets over the electrical boards. The power fed into a socket is always via a switch as explained above. External appliances may be plugged into a socket and switched ON to operate, and vice versa. Sockets are available in 2 or 3 pin types. In 3-pin types the third or the top pin is provided for the earth or the ground connection. It helps in grounding or neutralizing any dangerous residual electrical potential that may be hanging over the connected appliance’s body.

DPDT Switch, Wiring Diagram, Image

Main DPDT Switch: It may be considered as the entrance or the gateway for electricity and thus has to handle huge loads. It’s also a kind of switch but is much robust and designed to withstand high magnitudes of current through it. DPDT stands for Double Pole Double Throw as these may be operated manually to isolate both the wires of the supply line all at once for ultimate safety (Refer Diagram). It also incorporates an in-built Fuse to safeguard the whole house wiring in case of a short circuit.

Main Switch DPDT, Image

Electrical Load: Any electrical gadget that needs to be operated using electricity constitutes an electrical load. Every piece of electrical equipment from an incandescent bulb to the refrigerator that consumes electric power to remain operative is an electrical load.

The next page will deal with the various home electrical wiring diagrams, so let’s see how we proceed with them.

Designing Home Wiring Layouts

The following explanation will help you understand better how to design home wiring layouts:

How to Wire a Switch and a Load (a Light Bulb) to an Electrical Supply: As can be seen in the diagram the wiring is pretty simple. The Phase is invariably applied to one terminal of the switch, the other terminal moves to one of the connections of the load, and the other point of the load continues to finish at the Neutral of the supply line. Toggling the switch will alternately switch the bulb ON and OFF.

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How to Wire a Light Switch, Circuit Diagram, Image

How to Connect Two Switches in Parallel to Operate a Single Load: In the above example if an additional switch is connected to the existing one in parallel, either of them may be used to switch ON the bulb. And if desired, one switch may be located far away for remote operation of the light. But here, to deactivate the load (Bulb), both the switches will need to switch OFF.

How to Wire Switches in Parallel, Circuit Diagram, Image

How to connect Two Switches in Series to Operate a Single Load: If two switches are connected in series to the above network (see the figure below)), both of them will need to be switched ON to energize the load, but, toggling OFF any one of the switches will be enough to extinguish the light.

How to Wire Switches in Series, Circuit Diagram, Image

How to wire a Socket with a Switch to an Electrical Supply: The below given diagram shows a simple method of connecting a socket with a switch. Here, the Phase as usual and mandatorily is connected to one terminal of the switch and its other terminal is wired to the RIGHT hand side terminal of the socket. The LEFT hand side terminal of the socket goes to the Neutral line of the supply voltage.

How to Wire Wall Sockets, Circuit Diagram, Image

How to Interconnect a Switch, a Fan and a Fan Regulator to an Electrical Supply: With the help of the figure (shown below), one can easily see the simple concept of joining a fan, a fan regulator and a switch to an electrical supply. The idea is simple, just go on connecting each of them in series to one another. The diagram is self explanatory (Remember, the Phase always needs to be connected to the switch).

How to Wire a Ceiling Fan, Circuit Diagram, Image

The basic home electrical wiring diagrams described above should have provided you with a good understanding. Hopefully this should help you in designing your own home wiring layouts independently. If in any sort of problem, feel free to exchange your thoughts with me (comments need moderation, and may take sometime to appear).


Electrical house wiring involves Lethal Mains Voltages and extreme caution is recommended during the course of any of the above operations. The author holds no responsibility under any circumstance.

You are responsible for complying with all local regulations covering home electrical wiring. Your local zoning board may be a good place to start if you have questions.