threethreeThese 3 way switch circuits control multiple lights
|Two lights between 3 way switches (power via a switch)|
|Two lights between 3 way switches (power via a light)|
Three way switch lighting circuit diagrams
Here is our selection of three way light switch circuit diagrams. This is where two switches control the same light (or lights).
The electrical symbol indicates where power enters the circuit.
Here we have multiple lights controlled by 3 way switches.
The hot from the power source (cable C1) connects to the common terminal of the first 3-way switch (SW1) and the neutral is spiced, in the switch box SB1, through to the second 3-way switch (SW2) via the 3 wire cable (cable C2, that also carries the travelers that connect the two switches) where it is spliced through to the first fixture (F1) and connects with the neutral of each light. In the same way, the hot from the common terminal of the 3-way switch SW2 connects to the hot terminal on each light via cable C3 (spliced in fixture F1).
The power, cable C1, joins the circuit at the light fixture F1. Here the neutral connects to the light F1 and is spliced through to light F2. The hot from the power source is spliced through both fixtures and terminates at the common terminal of SW1 via cable C3.
The travelers of each switch are connect together using cable C4 (taped white and red wires).
Here we have a single light controlled by 3 way switches.
The hot from the power source connects to the common terminal of the first 3-way switch (SW1) and the neutral is spiced through (SB1) to the second 3-way switch (SW2) via the 3 wire cable (C2, that also carries the travelers that connect the two switches) where it is spliced through (SB2) to the neutral terminal of the light. The hot from the common terminal of the second 3-way switch (SW2) is connected to the hot terminal of the light.
You may also be interested to see how a two way switch works
You may also be interested to see how a four way switch works
A 3-way switch will usually have 4 screws. Most older 3 way switches only have 3 screws. The difference between the older and the newer switch is, the ground screw. Code changes over the years have required the addition of the ground screw for safety reasons. However, it is not needed for the correct operation of the 3 way switch. It is needed for the safe operation of this switch or any other type of switching device. On some switches the colors of the screw terminals are different to differentiate between the common and traveler screws. Some switches are made differently from others so the colors used may differ between manufacturers. The common screw will nearly always be a different color from the traveler screws.