Electrical Partrs & Materials

# How to Wire a Light Switch - Diagram 1

 By Dave Rongey Summary: Easy to Understand Light Switch Wiring - Fully Explained Light Switch Wiring with Diagrams and Pictures with Step-By-Step Instructions to Guide You.

## Understanding the Basic Light Switch for Home Electrical Wiring

Please Note: To illustrate the wiring of these switches, Switch Boxes and Fixture Boxes are not shown but are obviously required for every application.
These diagrams are shown as using the Romex wiring method.

These Romex cables contain a ground conductor which is required for all applications as well.
The ground conductors are always bonded together to insure the integrity of the ground path.

If you are using metal boxes, the ground conductor must be attached to each box by using a threaded ground screw or provided attachment. The frames of the switches which have a ground screw are to be attached to the ground conductor as required.

• # How to Wire a Single Switch

• ## Featuring Wiring Diagrams for Single Pole Wall Switches Commonly used in the Home.

Explanation of Wiring Diagram #1

• Switch wiring shows the Power Source (Power In) starts at the switch box.
1. Circuit electrical wiring enters the switch box
2. The Black Wire - Power In (source) attaches to one of the switch screw terminals
3. Fixture wiring exits the switch box
4. The Black Wire - Power Out wiring attaches to the other switch screw terminal
5. The White Neutral wires splice together
6. The ground wires splice together and bond to the switch and the box

NOTE: Switched 'White' wires are shown in a different wiring diagram

• Single Switch Applications

• Ceiling Light Fixtures
• Switch Controlled Outlet
• Half-Hot Wall Outlet
• Ceiling Fan and Light
• Single Wall Switch Types and Styles

• Standard Toggle Switch
• Flat Rocker Switch
• Dimmer Switch
• Some Home Automation Switches

### Wiring a Single Pole Switch

Question: Your example shows 2 wire Romex but most Romex I have seen has three wires one white-one black and an un-shrouded copper ground wire. What is the correct connection for this ground wire?
Jerry,

Answer: As explained in this page above: These Type-NM cables contain a ground conductor which is required for all applications as well. The ground conductors are always bonded together to insure the integrity of the ground path.
Dave

• ### Flickering Lights May Require a New Light Switch

• I have a light fixture that can be turned on/off by 2 different switches. Sometimes when I flip either switch, the light does not come on or it flickers and then turns on…
• ### My light fixture does not work right, what is wrong?

• I just put up a new light fixture. The light switch was off, I put the new bulb in and light was on…
• ### How to Wire an Outlet from a Switch

• Wiring Electrical Outlet for the Home – Home electrical which wiring includes 110 volt outlets and receptacles which are common place in every home. See how wiring electrical outlets for the home are done.
• ### How To Wire a GFCI and Outlet to a Light Switch

• Fully explained wiring instructions complete with a picture series of an installation and wiring diagrams can be found here in the GFI and Light Switch area here in this website. Just click the Wiring Diagrams….

Question from John in Lexington, Kentucky:
How is the Wiring for a New Light Switch and Fixture added to an Existing Switch?

I have an existing light switch, and I want to add a second switch for a new light that will be operated separately. The power comes into the switch which operates a single light at the end of the circuit. I know I have to change the gang box and I’m fine with running cable and installing plates but I’m not clear on the best way to add the wiring. Is there a simple way to do this or should I get an electrician?

Adding a Light Switch and Fixture to an Existing Switch

The task of installing additional wiring for a light switch and new light fixture will depend on available access to the proposed location. Hiring a qualified electrician will ensure that the installation is performed correctly where the existing circuit wires will be identified, and new circuit wiring will be extended to the new light switch and then out to the new light fixture. The method usedÂ to install the new wiring will depend on the wall structure and location in the home. Special attention will be given to the existing circuit capacity, the wire type and size, as well as making sure the additional wiring is protected and installed according to all the electrical codes that will apply.

How do I close off an existing light and add two new lights off of the existing light switch?

I have a single light on a single switch in my kitchen ceiling. I want to close off the existing light and run two new lights off of the existing light box. It is not far from the existing light, so will I need to run wire from existing box to the two new boxes. How do I wire it considering I don’t want a light fixture in the current spot. How do I close it off?

Adding New Light Fixtures off an Existing Light Switch

The easiest way to add new light fixtures is to run the new wiring to the existing light fixture, splice the wires together as the old fixture was connected and then place a decorative blank cover over the fixture box. Arlington makes a white blank fixture box cover that works very well for this type of application.
If you would like to remove the light fixture box, and there is access to the attic area then the fixture box could be removed, and the wiring installed into a new junction box located in an accessible location where the new wiring for the additional light fixtures may be connected. The new junction box must be securely mounted and an blank cover must be installed after all the wiring connections have been completed.

Question from Rob, a Homeowner in Ottawa Canada:
I have what I am sure is a simple question, but I want to be sure as the new light switches I want to install are expensive digital switches.

The new switches are obviously meant to be 3-way as they have a Red wire in addition to Black, White, Green. The old switches are not 3-way though and the electrical box they are in does not even have RED wires. The one old switch is the only switch controlling one light, while the other old switch is the only switch controlling three other lights.

So when I put the new switches with the Red wires in the box, what do I do with the Red wires?

My guess would be that I just cap off the Red wires from the new switches as they are not needed, but I do want to be sure.

You are correct, when s new switch will not be used as a 3-way switch the Red wire is capped off with a small wire connector or electrical tape.

Electrical Wiring Question
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## See How to Wire it Right!

Complete Guide to Home Electrical Wiring
Perfect for Homeowners, Students and Electricians
Includes:
Methods of Home Electrical Wiring
Wiring Diagrams for Switches, with 3-Way, 4-Way
Wiring Diagrams for 120 Volt and 240 Volt Outlets
Wiring Diagrams for GFCIs'
....and much more.

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