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I'm trying to connect two separate circuits from a single power source using 3way switches. My trouble seems that my wire from my light and my power source are in the same box. Is there a way to do this? I have wired it multiple ways and I keep getting the first switch almost Ike a master that needs to be on for the second circuit to work.

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You need 14-3 or 12-3 going to each switch from the light/power:

Call the switches L(eft) and R(ight):


  1. LineInPwr(white) -> Lamp(white)
  2. LineInPwr(black) -> L(white tagged black)
  3. LineInPwr(gnd) -> tied in common Both L(gnd) and R(gnd)
  4. L(black) -> R(black) [traveler]
  5. L(red) -> R(red) [traveler]
  6. R(white tagged black) -> Lamp(black)

Connections at L switch:

  1. L(White tagged black) -> L SW (common)
  2. L(Black) -> L SW (brass) [traveler]
  3. L(Red) -> L SW (brass) [traveler]
  4. L(gnd) -> L SW (gnd)

Connections at R switch:

  1. R(White tagged black) -> R SW (common)
  2. R(Black) -> R SW (brass) [traveler]
  3. R(Red) -> R SW (brass) [traveler]
  4. R(gnd) -> R SW (gnd)

Our own BMitch provided an answer and diagrams here (originally found here). We differ slightly in wire assignments (mine's better ;-)(why? both switches have the same wire assignments, the magic happens at the light)), but its basically the same. enter image description here

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Would love to see a diagram! Thanks' – Greg Sep 8 '13 at 0:01

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