Traveler Wires: How Do They Work?

Three-way switches are used to control ceiling light fixtures or other fixtures from two different locations. For example, a long hallway or stairway might use a three-way switch at each end so that lights can be turned on or off from either end. These switches have three terminal screws plus a ground screw. Two of the terminals are a light colour and are called travellers. The single dark-coloured screw is known as the common terminal. The ground screw is usually green. The traveller wires run between the two three-way switches, offering two potential pathways to complete the circuit and send power onwards to the light fixture.

Two 3-way switches are always used in pairs

A 3-way switch has no "on" or "off" markings because the toggle can turn the light on or off in either position, depending on the position of the other switch's toggle. A 3-way switch has three terminal screws plus a ground screw. Two of the terminals are a light colour—bronze or copper-coloured—and are called travellers. The single dark-coloured screw is known as the common terminal. The ground screw is usually green.

The two traveller terminals are used to connect the "traveller" wires, which 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 traveller wire goes to which traveller terminal on the switch; the traveller terminals are interchangeable.

The common terminal is the bridge between the power supply and the load

A three-way switch is used to control ceiling light fixtures or other fixtures and is commonly used to control one light fixture from two different locations. A three-way switch has four different screw terminals on its body. The single dark-coloured screw is known as the common terminal. The common terminal is the bridge between the power supply and the load. It is usually a darker colour than the travellers, such as dark brass, copper, or black.

The common terminal serves one of two purposes depending on where it is positioned in the circuit run. It either accepts the incoming black (hot) wire from the power source or connects to the black (hot) wire that leads onward to the light fixture. The hot wire brings the power from the source and delivers it to the first switch and then from the second switch to the light fixture.

The common terminal is essential for the proper functioning of a three-way switch, ensuring that power flows smoothly from the power source to the light fixture or load.

The traveller wires run between the two 3-way switches

The traveller wires are an essential component of a 3-way switch setup, which allows a light fixture to be controlled from two different locations. This type of switch is commonly used in hallways, stairwells, or large rooms, where it is convenient to be able to turn the lights on or off from multiple entrances.

A 3-way switch has three terminal screws: two "traveller" terminals, which are light-coloured (bronze or copper), and a single "common" terminal, which is a darker colour (dark brass, copper, or black). The traveller wires run between the traveller terminals of the two 3-way switches, offering two potential pathways to complete the circuit and send power to the light fixture. The traveller wires are interchangeable, so it doesn't matter which traveller terminal on a switch they are attached to.

The traveller wires are "hot" wires, meaning they carry power when the switches are on. For safety, if a traveller wire is white (usually indicating a "neutral" wire), it should be labelled with black or red tape to indicate that it is, in fact, a hot wire.

The traveller wire setup allows either of the 3-way switches to control the light fixture at any time. When the toggles on both switches are up or both are down, the circuit is complete and the light is on. When the toggles are in opposite positions, the circuit is interrupted and the light turns off.

The traveller terminals are interchangeable

Three-way switches are used to control ceiling light fixtures or other fixtures from two different locations. For example, a long hallway or stairway might use a three-way switch at each end so that lights can be turned on or off from either end.

Three-way switches have four screw terminals: a green grounding screw, a common terminal, and two traveller terminals. The common terminal is usually a darker colour, while the traveller terminals are usually a lighter brass colour. The traveller wires connected to these terminals offer two different pathways for power to travel from one switch to the other.

3-way switches are used in stairwells, hallways, and large rooms

A 3-way switch is designed to work in tandem with another 3-way switch to achieve this functionality. Unlike a standard single-pole switch, a 3-way switch has three screw terminals: two "traveler" terminals and one "common" terminal, along with a ground terminal. The two traveller terminals are usually a light colour, such as brass, bronze, or copper, while the common terminal is a darker colour, such as dark brass, copper, or black. The ground terminal is usually green.

In a standard 3-way setup, the power source is connected to the common terminal of one switch, while the light fixture or appliance is connected to the common terminal of the second switch. The two traveller wires span between the switches, linking the traveller terminals of both switches. This setup allows either switch to control the on-off function of the light fixture or appliance at any time. When both toggles are in the same position (both up or both down), the circuit is complete, and the light or appliance is turned on. When the toggles are in opposite positions, the circuit is interrupted, and the light or appliance is turned off.

The term "3-way" refers to the three possible pathways that the electrical current can take: through the first traveller wire, the second traveller wire, or remaining off. This functionality is achieved through a specific wiring method that allows the switch to toggle the circuit between open and closed states.

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