Three way switch wiring with 2 wire?

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Old 01-31-06, 10:16 AM
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Three way switch wiring with 2 wire?

Can the following be done

I have a light switch at the top of my stairs 14/2 it controls a light at the bottom of my stairs. I want to install a second switch at the bottom of the stairs to also control that light (either before or after the light). At this point it is all two wire. i know if i could run 3 wire from the switch to the light, or to the second switch, life would be grand but that would mean tearing up drywall that i do not want to do. Can it be done with 2 wire or am i doomed to a life of running up and down the stairs. I ask this because the house is all two wire, up on the second floor there is a switch that controls a light on the first floor as well as a switch on the first floor that controls that same light. There must be a way to do this with two wire?
 
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Old 01-31-06, 04:14 PM
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Can't be done without a three wire cable to the switches.
 
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Old 01-31-06, 06:47 PM
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And I believe that code requires switches on both the top and the bottom of a staircase.

Just a word of caution, my neighbor was going to attempt to wire a three-way switch using existing 14/2 wiring, but using the GROUND wire as the third wire.

Obviously I stopped him and let him know the dangers of this.

It's tempting, but don't do it.

With some good fishing skills, you're drywall destruction can be kept to a minimum.
 
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Old 02-01-06, 06:27 AM
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Alright i thought that may be the case where i need three wire. Time to dust off the old fishing skills. Now one side question would anyone recommend just buyiing the third wire and fishing up that single wire or do you think i am better to just pull a new length of 3 wire? I hope the current wire is not stapled too much along the run. The run is only about 5 feet but it runs up under some stairs and then up the wall.
 
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Old 02-01-06, 08:34 AM
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I think that's a hazard as well. I believe all the wires need to be jacketed.
 
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Old 02-01-06, 10:19 AM
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You don't need a three-way switch if you install a motion sensor. Is the placement of your existing switch such that the sensor could "see" you?
 
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Old 02-01-06, 04:30 PM
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You can't fish a single wire that would be a code violation unless you have conduit. You must fish a cable.
 
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Old 02-17-06, 10:13 AM
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2Threeway switches controlling 2 lights

I followed this wiring instruction book which I borrowed from the library.Everything is fine after installation except the switches has to be in a "on"position before the light comes on and they are in a opposite "on" or "off" position.I always thought with the 3-way switches you can always switch the light on or off on any switch.Someone can help?I wish I could post the wiring instruction here with the pictures.
 
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Old 02-17-06, 10:49 AM
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You can switch the light on/off from either switch at any time in a properly setup threeway switch circuit. It is possible you have not got the correct wire on the common screw of one or both threeway switches. The common screw is not in the same place on all brands of threeway switches. It is the one labelled 'common' or the one colored black.
 
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Old 02-17-06, 10:59 AM
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I didn't quite understand what you said. If what you meant was that switch "B" cannot turn on and off the light unless switch "A" is in one certain postion, then you mixed up the "common" on one or both switches. But if what you meant was that the light is on when both switches are down or both switches are up, but off when they are in opposite postions, then you can solve that (if you perceive this to be a problem) by turning either switch upside down, or by reversing the traveler connections on either switch.
 
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Old 02-17-06, 01:18 PM
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To be more specific,I have the power source coming into switch A and did all the connections with respect to what the picture(colored) showed on the book to arrive at switch B.The common terminals are black and I cant be wrong on this one.The lights just wont turn on unless both switch are on a "on" or "up" position and you can toggle the light on and off at either switch however if at any time one switch is in a opposite position,this would not happen.I did try reversing the wire connections on both switches and still the same thing.BTW thanks for the prompt response again.
 
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Old 02-17-06, 03:04 PM
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If you're sure you have the commons correct, then the explanation is that one of the travelers is not well connected at one end or the other, or is broken in between. However, your symptoms are also consistent with a misidentified common at one switch. Double-check your work again.

Can you provide us a diagram of what you have?
 
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Old 02-17-06, 05:15 PM
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I believe this is what you have. Note the postion of the comomn screw is not the same on all switches. It is black on all switches.


http://www.selfhelpandmore.com/switc...y/3waysame.htm
 
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Old 02-18-06, 10:38 AM
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I re-checked my work and all the wire connections,bypassed one light fixture and even went for another instruction guide with the same end result until I used my spare switch alternatively at both end,and "bang",the light worked as it should be.Switch A was at fault from the start.
Thanks for pointing this out to me,it was a good working experience really.Thanks guys.
 
 

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