How should a 3-way switch be wired?

Quote from the video:
Quote from Youtube video: Now you're going to connect the neutral wire from the power coming in to the neutral wire in the common cable between the two switches. Now you're going to connect the red wire and the black wire.

Does it matter where the traveler wires go on a 3-way switch?





The traveler wires run between the two 3-way switches, offering two potential pathways to complete the circuit and send power onward to the light fixture. It makes no difference which traveler wire goes to which traveler terminal on the switch; the traveler terminals are interchangeable.

How do I replace an old 3-way switch with a new one?

Quote from the video:
Quote from Youtube video: Common so these two are the traveler wires to get these backstab wires out of the old switch. You can either cut them off flush.

What color wires go on a 3-way switch?

3-Way Switch Wire Colors



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.

Where does red wire go on 3-way switch?

The black hot wire connects to the far right switch’s common terminal. Red and blue wires link traveler terminals of both switches. The red wire, which is connected to the first switch’s common terminal, leads back to the fixture.

Can I connect red and black wires together?





These wires are typically used for switch wiring as well as the interconnection between smoke detectors hard-wired into the power system. You can link two red wires together, or you can link a red wire to a black wire. Since red wires conduct current, they are considered hot.

What color wire goes to the black screw on a 3-way switch?

Tighten the terminal screws. Connect the ground wire to the green screw, then connect the wire marked common to the black or dark colored screw. Connect the two remaining traveler wires to the two brass or light colored screws.

What is the common terminal on a 3-way switch?

There are three screw terminals on the body of the switch, in addition to the green grounding screw. One screw, known as the common, is a darker color than the others. The other two screws, usually a lighter brass color, are known as the traveler terminals.

How many wires are needed between 3-way switches?

three wires



With a three-way switch, three wires connect the pair of switches—two black “traveler” wires and a third “common” wire. When the circuit’s power is turned on, any of these may be “hot,” depending upon how the switches are toggled.

How do you identify a load and line wire?

Load Wire – Generally connected to the top half of your switch. If the wire is coming from the top of the switch box, it is likely your load wire. Line Wire – Generally connected to the bottom half of your switch. In some cases, line wires are marked with “line”, “pwr”, or a lightning bolt symbol.

Does the red wire connect to black or white?

Attach the black wire to the outlet you want to always be on (usually the top one) and the red wire to the switched outlet. Connect the white wire to either of the chrome screws (remember, they are still joined) and the ground wire to the green ground screw.

Where does the red wire go on a light switch?



Attach the white wire from the light fixture, which is now the hot wire, to the nut at the top right of the switch. Attach the red wire from the light fixture to the nut at the top left of the switch. Connect the bare copper wire to the green nut at the bottom left of the switch.

What do you do with the red wire?

The exact purpose of a red wire for a light fixture can vary. Except in rare cases, it is a hot wire or a switched hot wire. Check the wire with a non-contact voltage tester with the power and switch turned on. If the tester indicates the wire is hot, turn the switch off and retest.

Where do the red and black wires go on a light switch?

Basic Knowledge of How to Wire a Light Switch

  • Black Wire – This is the hot or load wire.
  • White Wire – This is the neutral wire.
  • Bare Copper (Green) Wire – This is your ground wire.
  • Red Wire – This wire is used for 3 or 4 way switches and will connect the switches together so they can each control your lights.


How do you know which wire is hot and black?



As a further test, place the prongs of the multimeter’s wires on the bare metal on the ends of the two black wires. You will get a reading if one wire is hot and the other isn’t. However, if both wires are hot, the reading will be zero.

What happens if you mix up hot and neutral wires?

This happens when the hot and neutral wires get flipped around at an outlet, or upstream from an outlet. Reversed polarity creates a potential shock hazard, but it’s usually an easy repair. Any $5 electrical tester will alert you to this condition, assuming you have a properly grounded three-prong outlet.

Does it matter where the hot wire goes on a switch?

In the case of a single-pole switch, these wires are interchangeable—it doesn’t make any difference which wire is attached to which screw terminal. Inside the switch is a metal pathway that closes when the switch is in the ON position and opens to interrupt the flow of power when the switch is turned OFF.

What happens if you connect the wrong wires on a light fixture?

But here’s the catch: If you connect the circuit wires to the wrong terminals on an outlet, the outlet will still work, but the polarity will be backward. When this happens, a lamp, for example, will have its bulb socket sleeve energized rather than the little tab inside the socket.

Can wiring a light switch wrong cause a fire?



Usually, a broken or failing light switch isn’t a fire hazard itself, but it can overheat if the contacts or the switch wear down. Sometimes a bad light switch can cause other components on the circuit, such as a bulb, to become a fire hazard by causing an intermittent current.

How do you tell which wire is which?

Here’s a rundown of electrical wires: The black wire is the “hot” wire, it carries the electricity from the breaker panel into the switch or light source. The white wire is the “neutral” wire, it takes any unused electricity and current and sends it back to the breaker panel.