3-way switch wiring

Discussion in 'Electrical Forum discussion & Blog' started by sucosam, Oct 13, 2009.

  1. sucosam

    sucosam New Member

    Messages:
    2
    Location:
    Canada
    Hi folks,

    Thanks for taking time to read this. I will explain how this is currently configured, hopefully it doesn't get too messed up. But the scenario is that the switch at the top of my stairs controls the basement lights. The switch at the bottom only acts as a main power switch, that is to say, if the bottom switch is ON, the top switch will work properly, if the bottom switch if OFF, the top switch does not work at all.

    From junction box, 14/3 cable (black, white, red, ground) goes to the 3-way switch at top of stairs (looking at switch, common terminal is black screw and up top, let's call one silver screw T1, and across from that is let's say T2)

    T1 _ T2
    Gnd _ Common

    Black - goes to T2
    White - goes to other white cables
    Red - connected to red from other 14/3 that goes to Bottom switch

    So on the switch T1 has nothing connected to it. T2 has black from junction box. Common has black going to switch #2.

    Switch#2 has Red on T1, White on T2, and Black on Common

    I know this is wrong, but I've tried a few different configurations, but they either don't work at all, or trip the breaker. Can anyone offer a suggestion as to how the 14/3 from the junction box should be attached to Top switch? Then I just need to hook it up to Bottom switch.

    I should also note, that from Top switch, there are two additional single-pole switches that the top 3-way feeds power into.
    Last edited: Oct 13, 2009
  2. Billy_Bob

    Billy_Bob In the Trades

    Messages:
    422
    The following is how a 3-way switch works. This diagram shows the neutral and ground wires going through the switch boxes, but this is not always done. Sometimes just the wires for the switches are run to the boxes...

    [​IMG]

    Then with an ohm meter or a continuity tester and the WIRES DISCONNECTED FROM THE SWITCH, you can place the test leads on a switch and see how it operates. Here is info on using a continuity tester...
    (NEVER do this with power on, it will wreck your tester!)

    http://www.dinosaurelectronics.com/Test_Fuse.htm
  3. sucosam

    sucosam New Member

    Messages:
    2
    Location:
    Canada
    The one difference I see in this diagram is that the power supply has just Black, White and Gnd whereas the wiring in my house also contains a red wire. Should this be connected to anything from the source? or just between the two switches?
  4. Billy_Bob

    Billy_Bob In the Trades

    Messages:
    422
    It is not a matter of connecting wire colors, rather it is understanding which wire goes where and what the wires are connected to at the other end.

    So what does the "red" wire go to?

    Or for that matter, where do all the wires go and what are they connected to at the other end?

    Learn this, learn how the switches function, then you can draw yourself a wiring diagram.

    BTW this is something which takes a bit of experience. Being able to look at wires and determine what wires are for what. Where they go. What they are connected to at the other end. And being able to do a bit of testing to help determine this. So might want to hire an electrician. Not a big job, so shouldn't cost very much.
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