Wiring Diagram For 3 Way Switch
No longer allowed after NEC if no neutral wire in switch boxes. Line voltage enters the first 3- way switch outlet box, light fixture is located between switch boxes. There is no standard for wire colors on 3- way switch travelers. The colors will vary depending on whether NM cable or conduit was used. With NM cable, the wire colors for travelers will be black and red using 3- wire cable. With conduit, the wire colors for travelers could be any color. In the 2nd diagram below, blue wires are used for travelers.
In the 1st diagram below, a 2- wire NM cable supplies power from the panel to the first switch box. The black line wire connects to the common terminal of the first 3- way switch.
A 3- wire NM connects the traveler terminals of the first and second 3- way switch together. Traveler wires are interchangeable on each switch. The common terminal of the second 3- way switch connects to the light fixture s. The white neutral wires are connected together in each switch box. Diagrams shown on this page are simplified for clarity. Electrical outlet boxes can have numerous NM cables going in and out.
See Actual Switch Box Wiring. Ground connection diagram is shown separately. With conventional wiring, line voltage enters the first 3- way switch box. Black common wire is usually wrapped around the two traveler wires on a 3- way switch.
Wire 3 way Switches and other Wiring Diagrams
Alternate 3- Way Switch Wiring. Question or Comment? No longer allowed after NEC if no neutral wire in switch boxes 3- Way Switch Wiring Diagram Light Fixture Between Switches Line voltage enters the first 3- way switch outlet box, light fixture is located between switch boxes.
With conventional wiring, line voltage enters the first 3- way switch box 3- Way Switch Wiring Diagram, Conduit.How to wire a 3-Way switch. Wiring a 3-way switch is a little more tricky than wiring a 2-way switch. First of all we need to go over a little basic terminology on switches. It should also help in understanding the functions of each type of switch.
Then a 4-wire cable going between the two 3-way switches and then a 3-wire cable going from the switches to the load. The 3-wire cable consist of a black wire, a white wire and a bare copper wire, while the 4-wire cable has an added red wire which is hot as well.
When wiring a 3-way switch circuit, all we want to do is to control the black wire hot wire to turn on and off the load from 2 different locations. The diagram below will give you a better understanding how this circuit is wired. Notice that there is a 3-conductor cable coming into the first box, then a 4-conductor cable going from left box to right box, then a 3-conductor cable going from the right box to the load.
Now for wiring, lets assume you're looking at the switch just like it shows. The Left Box: The lower left screw is the common and gets the black wire from the source 3-cond. The upper left screw gets the black wire from the right box 4-cond.
The upper right screw gets the red wire from the right box 4-cond. The white wires tie together with a wire nut. The bare copper wires tie together with a wire nut. Be sure to attach a bare copper wire to the green screw on the switch. The Right Box: The lower left screw is the common and gets the black wire from the load 3-cond. The upper left screw gets the red wire from the left box 4-cond.
The upper right screw gets the black wire from the left box 4-cond. Follow along with the mouse pointer as we go through this. The source power black wire is coming in from the left. It ties into the common on the left switch.
When the left switch is toggled, it connects to the upper circuit and now the circuit is open at the right switch which turns off the light. Toggle the right switch and it connects to the upper circuit and now closes the path and turns the light back on and so on.This page contains wiring diagrams for four different types of household lamps. Included is a diagram for a two-circuit lamp switch to control a standard lamp socket at the top of the lamp and a smaller socket at the base for a low wattage bulb.
Also included are diagrams for a standard lamp switch, a three way lamp switch, and a vintage floor lamp with 4 light bulbs. Lamp cords are usually all one color making the standard black-hot, white-neutral guidelines useless for determining polarity. Other methods are therefore used to determine the polarity on a lamp cord. First, check the insulation on the cord wires closely and you will find either a textured bead or a thin colored line running along one wire, this is the neutral wire.
The plain wire is the hot. If the cord isn't marked with a bead, then the strands of wire may be different colors to distinguish between them. In these cases, the silver-colored wire is usually the neutral and the brass-colored wire is the hot.
Another clue to polarity is the plug on the lamp cord, the wide prong being the neutral and the narrow one the hot. Most older lamp cords will have prongs that are the same size. This is because polarity was not observed on electric lamps until the development of grounded circuits.
With these lamps, the plug can be plugged into the receptacle outlet in either direction making polarity a non-issue. This diagram illustrates the wiring for a bedside lamp with two sockets. The top socket Aholds a standard incandescent bulb. The second socket Btypically holds a small, low-wattage bulb similar to a night light bulb. The switch allows for energizing the top bulb only, the night light only, both bulbs at once, or for turning both bulbs off.
This type of switch will be referred to as a 2 circuit lamp switch when shopping at home stores. Don't mistake this for a three way switch pictured belowthe two do not function in the same way. Here a 2-way push-button switch is wired to a lamp with 2 bulbs.It is important to understand how these are wired before attempting to troubleshoot or replace. The diagrams below show the conventional wiring for 3- way switches. Unfortunately, not all 3- way switches are wired the conventional way.
If you have any problems with these switches, it may be best to call an electrician. All of the switches shown below are 3- way.
With conventional wiring, the common wire from one switch connects to line, the common wire from the other switch connects to the load lights. The pair of travelers on one switch connect to the pair of travelers on the other switch. Usually, the common wire is wrapped around the traveler wires for identification in the 3- way light switch electrical boxes. Ground connection is not shown in these diagrams. Both switches are toggled down to create an open path, light is off.
Left switch is toggled up to create a continuous path, light is on. Right switch is toggled up to open the path, light is off. Left switch is toggled down to create a continuous path, light is on. Travelers can be wired in either of the below examples. Toggling either of the 3- way switches will cause a closed path to open, or an open path to close. Troubleshoot 3- Way Switches. Alternate 3- Way Switch Wiring. Question or Comment? Conventional 3- Way Light Switch Diagrams.
Diagram 1. Diagram 2. Diagram 3. Diagram 4. Toggling 3- Way Switches. Alternate 3- Way Wiring.This page is dedicated to Wiring Diagrams that can hopefully get you through a difficult wiring task or just to learn some basics in how to wire a 2-way switch3-way switch4-way switchoutlet or entertainment component diagrams.
If you don't see a wiring diagram you are looking for on this page, then check out my Sitemap page for more information you may find helpful. How a 2-Way Switch Works. The power source is coming in from the left. Notice the black wire is the only wire that we are controlling through the 2-way switch. You have an incoming hot wire black going to one screw it does not matter if you use the brass or silver screw on the side of the 2-way switch and a black wire from the other screw on the 2-way switch going to the load light, ceiling fan etc.
The white wires are wire nutted together so they can continue the circuit. Just use your mouse pointer on this diagram and follow the current flow from black wire hot wire through the 2-way switch, then to the load and return through the white wire neutral. This should give you a good basic understanding how the 2-way switch circuit works and will help you in adding or changing a 2-way switch. How a 2-way Switch Circuit Looks. So the circuit above when explained should give you a good concept on how this basic circuit works.
When wiring a 2-way switch, this image on the left will show how the connections should actually look when all connections are made. Take notice of the ground wire. It's very important that the ground or bare copper wire is connected to the green screw on the switch. All grounds are connected, and the ground is connected at the light when possible. If no connection is available, then attach the ground wire to the box in a solid way.
How a 3-Way Switch Works.
How to Wire a 3 Way Light Switch
When wiring a 3-way switch circuit, all we want to do is to control the black wire hot wire to turn on and off the load from 2 different locations. The diagram here will give you a better understanding how this circuit works and how a 3-way switch is wired. The source power black wire is coming in from the left. It ties into the common on the left switch see image below. When the left switch is toggled, it connects to the upper circuit and now the circuit is open at the right switch which turns off the light.
Toggle the right switch and it connects to the upper circuit and now closes the path and turns the light back on and so on. How a 3-Way Switch Circuit Looks. So the circuit above when explained should give you a good concept on how this 3-way circuit works. When wiring a 3-way switch, this image on the left will show how the connections should actually look when all connections are made.The Key to Wiring 3-Way Switches — The Power Feed and the Switch Leg leading to the fixture s typically, one at each switch location, are attached to the screw terminal found at one end of the switch by itself.
Three-way Switch Diagrams Fully Explained Wiring 3Way Switches 3-way switches are a convenient way to operate lighting fixtures from two locations. The Power Feed and the Switch Leg leading to the fixture s typically, one at each switch location, are attached to the screw terminal found at one end of the switch by itself.
This terminal is usually identified by a darker colored screw. To illustrate the wiring of these 3-way 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. 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. See also the wiring diagrams with pictures 3-Way Dimmer Switch Wiring Please contact me if you have any questions or comments regarding the wiring of 3-way switches. First my easy to understand chart helps to identify the 3-way switch system for the application:. Diagram 1 above, shows the electricity source starting at the left 3-way switch.
Wiring Diagrams for 3-Way Switches. The white wire of the cable going to the switch is attached to the black line in the fixture box using a wire nut.
The white wire becomes the energized switch leg, as indicated by using black or red electrical tape. Diagram 3 above, shows the electricity source starting at the right 3-way switch box, the same that has the Romex wire going to the fixture. Ask The Electrician Home Page.
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Important: Modifying existing electrical circuits or installing additional electrical wiring should be done according to local and National Electrical Codes, with a permit and be inspected.By code, the number of conductors allowed in a box are limited depending on box size and wire gauge.
Calculate total conductors allowed in a box before adding new wiring, etc. Check local regulations for restrictions and permit requirements before beginning electrical work.
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If the user is unable to perform electrical work themselves, a qualified electrician should be consulted. How to Read These Diagrams.
Three-way switches allow for controlling a light fixture from two separate locations, these are usually used at the top and bottom of a flight of stairs or at two different entrances to a room. On this page are several wiring diagrams that can be used to map 3 way lighting circuits depending on the location of the source in relation to the switches and lights. Also included, are diagrams for 3 way dimmers, a 3 way ceiling fan switch, and an arrangement for a switched outlet from two locations.
For more information about these circuits and troubleshooting tips check below. In this diagram, the electrical source is at the first switch and the light is located at the end of the circuit. Three-wire cable runs between the switches and 2-wire cable runs to the light. The black and red wires between SW1 and SW2 are connected to the traveler terminals. The hot source is connected to the common terminal on SW1 and the common terminal on SW2 connects to the hot terminal on the light.
The source in this circuit is at the first switch and the light fixture is located between SW1 and SW2. Three-wire cable runs between each switch and the light fixture.
The hot source wire is connected to the common terminal on SW1. The common terminal on SW2 is connected to the hot terminal on the light. The traveler wires are spliced at the fixture box to run between the traveler terminals on the switches, they are not connected to the light.
In this diagram the source for the circuit is at the light fixture and the two switches come after. The hot source wire is spliced at the light box to the white cable wire running to the first switch box.
There it is spliced to the black wire running to the second switch box, which is then connected to the common terminal on SW2. When a white wire is used for hot like this, it's marked with black tape or paint at the ends to identify it as hot.
Back at the light fixture, the hot terminal on the light is connected to the black wire running to the common terminal on SW1. At SW1, the red and white wires running to SW2 are used as travelers connecting the traveler terminals between the two switches. Again, the white wire is marked with black on the ends to identify it as hot. In this arrangement, the source for the circuit is at the light fixture which is located in the middle of the circuit. At the light, the hot source wire is spliced to the black wire running to the common terminal on SW2.
The hot terminal on the light fixture is connected to the black wire running to the common terminal on SW1. The red and white cable wires are spliced in the fixture box and run to the traveler terminals on both switches.
They don't connect to the light fixture. The white wire is marked black on both ends to identify it as hot. The following 3 diagrams show the wiring for a specially made dimmer that can be used in these circuits in place of either of the the 3 way switches, or both. This arrangement allows for lowering the lights in a 3 way circuit.
After the lighting level has been set on one dimmer, the other switch will turn the lights off and on at that level.