How To Wire A 3 Way Switch

You are currently viewing How To Wire A 3 Way Switch

Wondering how to wire a 3 way switch? Well you came to the right place. Let the professional electricians help you and make things simple.

The three way has a set of travelers that transfer the power from location to another. How to wire a 3 way switch depends on the power feed location. This is common on staircases.

how to wire a 3 way switch

Common methods to wire a 3 way switch would be too bring your feed from your fuse panel or power box. This will be done with a piece of 14/2 nmd 90.

The neutral wire would continue on through both 3 way switch boxes and terminate at the light fixture. Black wire of the feed coming from the panel. Would terminate on to the black common screw of the first 3 way inside your first box.

The other 2 wires in the 3 wire that connects between both boxes will get help to the travellers of both 3 ways. This would be the red and black wires as you have already used the white wire for your neutral.

These 2 wires we’re going to copper screws of both 3 ways. From the last 3 way to the light itself you will have one black wire left. This black wire will hook on to the common of the last 3 way. hey

Old Methods How To Wire A 3 Way Switch

how to wire a 3 way switch

Since the release of the 2018 electrical code . The code states that you must have a neutral present in all switch boxes. This is to allow for new style dimmers and a variety of smart light switches.

So long story short where do you wire the power through the switch boxes or whether you wire through the light fixture. You must have that neutral present in each which box. This can be done by simply wire nutting a tale onto the neutral as it passes through the box.

New Code Methods How To Wire A 3 Way Switch

Wire the 3 way with power in the switch

When wiring a 3 way with power in the light do you need to take a little different step. Power from the panel with 14/2 would come into the light box first or the octagon.

The white wire from the power panel would help directly on to the light fixture. Keep in mind if you’re following the new electrical code. You will need to run a piece of 14/3 down for what we called switch leg to switch boxes. This is so that you can carry down the neutral to the switch box.

The black wire from the piece of 14/3 running to the switch box should go all the way down to the first switch. This should have gone to the common black screw of the first 3 way.

Again between the 2 switches you will need that piece of 14/3 wire. The two travellers will again be here black and your red. From the second 3 way you will run the common wire backup on you’re red wire to the light fixture. This is because you’ve already used the black to go to the first 3 way. Sometimes this can be a little confusing.

We do one wire to time colour by colour and use the process of elimination.

how to wire a 3 way switch

Wire the 3 way with power in the light

Different types of 3 way switches

Different types of 3 ways that you will see in the store or installed in someone’s house . They are sometimes hard to tell what day are. A typical toggle 3 way just looks like a regular switch what is no indicator button to tell you when it is off. These are the most common 3 ways that you will see in homes.

A step up from this 3 way would be a decora style. Often referred to as a rocker switch this which is also have no indicator for up and down. Depending on which way they have 3 way is switched it will always be in a different position.

Wireless 3 way switches have been around for about 10 years . These types of 3 ways do not need to have travellers running between them. Providing you have a power source at each box.

The 3 ways communicate over the neutral line within the house. Finally the newest type of 3 way would be the smart switch. It’s really hard to call this type of switch 3 way because you can have multiple switch locations.

Anywhere in the house there is a power source available you can put one of the switches. The switch is simply program to your Wi-Fi. Providing one of the switches is talk to a light that you wanna control. You can control that light from several locations. You can even controller from the app on your phone.

How To Wire A 3 way Switch With Multiple Lights

Wiring a 3 way switch to multiple light fixtures is pretty much the same as wiring it with one light fixture. After running power to your first 3 way. Then running you’re 3 wire with your travellers.

You will terminate from the last comment do you like fixture. Simply run from the light fixture to the next light fixture and so on. Wiring all the black wires and all the white wires together in each light fixture.

What Kind Of Wire Do I Need For A 3 Way Switch?

Typically will use a piece of nmd 90. This is sometimes referred to in the US Romex or lumex. This type of wire should be 14 gauge 3 conductor. It actually has 4 wires inside. Usually a white a black and a red a company by bare copper ground wire.

Sometimes this wire also comes in a 12 gauge version . This is for larger lighting loads up to 20 amp. Make sure if you use this kind of wire that your 3 way switches rated for 20 up as well.

Why Is It Called A 3 Way and Not A Two Way?

The technical term is actually called a 3 way switch. This means that you can switch device like a light fixture or an from to locations.

Many people call this type of switch a 2 way switch because you can switch from 2 locations. Sometimes it gets confusing for customers.

What Kind Of Electrical Box Do I Need For A 3 Way

Any device box rated for switch is suitable for a 3 way. 1104 l or at 1104 lht. Plastic device boxes are also a common items used in the industry these days. You can even use a larger device box with reducer plastering.

Do I Need To Use The Screws Or The Terminal Tabs On The Back Of The Switch

Important yes you need to use the terminal screws on the back of the 3 way. Do not use the pinch down connectors on the switch itself. This is frowned upon in the industry and called taking the easy way out. The problem is when you load the switch up with power the little tabs become weak.

This causes arcing and eventually heat and fire.