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Build Guide · Lighting Control

Three-Way Switches

Control one light from two locations using a pair of 3-way (SPDT) switches.

Difficulty: BeginnerBuilds on: the complete circuitLesson: read the theory →

What you’re building

L1L2/N3-way A3-way B
Two 3-way (SPDT) switches and two travelers control one light from two places.

Parts to add

  • 1Power Source
  • 23-Way Switch
  • 1Light

Steps

  1. Add the parts

    Click Power Source, two 3-Way Switch, and one Light.

  2. Feed the first switch

    To wire, click the first terminal (it highlights), then click the second to connect them. Power goes to the common of the first 3-way.

    Power Source L1 3-Way A COM
  3. Run the two travelers

    Connect both traveler terminals of switch A to the matching travelers of switch B. These two wires are what let either switch change the path.

    3-Way A T1 3-Way B T1
    3-Way A T2 3-Way B T2
  4. Feed the light from the second switch

    The common of switch B feeds the light; the light returns to neutral.

    3-Way B COM Light (left)
    Light (right) Power Source N
  5. Energize and toggle

    Click Energize. Flip either switch — the light toggles. Either location controls it, no matter what the other switch is set to.

✓ Test it

  • Flip switch A: light toggles.
  • Flip switch B: light toggles.
  • Either location controls the light, regardless of the other switch’s position.
Tip: Think “which traveler,” not on/off. The light is on when both switches sit on the same traveler.

Open the Sandbox and build it

Follow the steps above with the trainer open in another tab.

Open the Sandbox →