Old Wiring, Three Way (or lack of) problems.

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  #1  
Old 05-10-14, 12:28 PM
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Old Wiring, Three Way (or lack of) problems.

All wires are black. There are two light switches that control one light in my house. When they functioned, both had to be in the "on" position for the light to be on. When messing with it, only one switch now functions. The functioning switch currently works regardless of whether the second switch is off or on.
The Blue switch is the one that currently works. It has three connections, one of them being the ground screw at the bottom (im guessing this is wrong). The other, older switch has two copper connections at the top and one black screw connection at the bottom. The bottom black connection is connected with a nut to two other wires in the wall (guessing this is the power supply?).

I cannot figure out which wire is which to replace the switches. I am assuming they are traveler wires and not a ground due to age (all black wires)
 
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Old 05-10-14, 12:48 PM
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The blue switch looks like it says On on the handle which is not a 3 way switch.

You are going to need a test meter and an extension cord to figure this out.
 
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Old 05-10-14, 01:12 PM
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I have a Volt meter and an extension cord I can plug into an outlet. My best guess is the previous owner either jerry rigged the blue not three way switch as opposed to replacing it properly when it must have failed. Is that possible? The wire connected to the ground screw is not a ground..
 
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Old 05-10-14, 02:10 PM
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Now that you have some test equipment we need label the wires aand connections. Then we will kill the power and remove the wires from the switches to determine the functions of each wire. You may need to run the cord to a grounded receptacle for some of the testing.
 
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Old 05-10-14, 08:58 PM
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Thanks for responding! Exactly what I have been trying to do but need some direction.
 
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Old 05-11-14, 05:49 AM
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First we need to find the power source in the box. You may need to use the cord as a portable ground to have a reference. After that turn the power off and connect two conductors together in a wire but so they are just touching. Switch the meter to continuity and go to the other switch. Measure between two conductors until you find the pair that gives you a tone. These are the travelers.
 
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Old 05-12-14, 12:57 PM
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I was able to identify that there is a hot wire in both switches. Should I just cap one?
 
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Old 05-12-14, 01:15 PM
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Meaning that with all wires disconnected, One of the three is hot in the blue switch and one of the four wires is hot in the old 3-way. I am able to then wire the switch but do I have a new problem? What do I do with the extra hot wire (the 4th wire in the old 3 way) and why would two hots have been used previously?
 
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Old 05-13-14, 07:01 AM
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I am just finding out that with the weird three way jack disconnected, two other lights do not work. Both of these lights are in adjacent bedrooms and are each controlled by its on switch. Previously, the two switches originally mentioned in this forum did not control either of those lights.
 
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Old 05-13-14, 09:11 AM
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Not aimed at you Andrew.
Jim, I wonder if this is one of the old fashioned 3-ways where you had a switched neutral and two SPST switches. One switch is SPST. Maybe the SPDT was added later.
 
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Old 05-13-14, 11:57 AM
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Perhaps a feed through connection was broken when the switch was removed. If you cap a pair of wires do the other lights come on? You may need to try more than one pair.
 
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Old 05-13-14, 11:59 AM
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I don't think that looks old enough to be a switched neutral, and have never seen it used in combination with a switched hjot also.
 
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Old 05-14-14, 11:17 AM
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I made this picture, I hope it helps. I separated all the wires. The Green switch at the bottom of the stairs has a hot and two travelers. The Blue light switch at the top of the stairs has a hot and two travelers as well as another wire. I have identified that the travelers go from the blue and green switches. With the switches disconnected, the red switches in the three rooms pictured do not work, and neither do the lights. If I connect the hot wire in the blue switch to the unidentified fourth wire in the blue switch, the red switches and lights work.
 
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Old 05-20-14, 07:23 AM
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Is there no one able to help? I feel like we are so close. Please!
 
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Old 05-20-14, 07:46 AM
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Sorry but I am lost. Lets make this simpler Pick one light you want to work. Tell us the color of all the wires at the switch and light. Tell us if power comes in at the switch or the light. Tell us if it is a 3-way. If it is tell us the wiring at both 3-ways.
 
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Old 05-20-14, 08:46 AM
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There is a light at the top of my stairs that has a black and a white. Two switches control this light. Both switches must be up (on) for the light to power. It can be turned off at either switch.

The two switches are the ones I have pictured.

The blue one was at the bottom of the stairs. It has three wires. One hot, two travelers.

The other switch looks (to me) like a three way without a ground. At this switch, there are four wires. One hot, two travelers and an additional wire.


To my surprise, now that the two switches are disconnected, all three bedroom lights and the bathroom light doesn't power. All the rooms have there own switches. (must be where the 4th wire in the 2nd switch comes in).
 
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Old 05-20-14, 09:32 AM
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The blue one was at the bottom of the stairs. It has three wires. One hot, two travelers.
What did you mean by "hot" and how did you determine it. If there are no other wires in the box then there is no "hot" only a common and two travelers. Is this a 3-conductor cable in the box?
The other switch looks (to me) like a three way without a ground.
Please Explain more fully. Do you mean there are two brass screws and one dark gray screw?
there are four wires. One hot, two travelers and an additional wire.
Are there two 2 conductor cables coming into the box? Again explain how you determined there was a "Hot". Are either of the switches marked on/off?

Answer all of thse questions and we will go from there.

Notes: Any measurement made with a non contact tester are not reliable enough to come to any conclusion about a wire. Measurements made to wires connected to a switch are not meaningful. To determine if a wire is hot you must disconnect and measure between it and its associated neutral or a known good ground. Grounds are not required for a circuit to function correctly and lack there of is usually not important.
 

Last edited by ray2047; 05-28-14 at 10:16 AM.
  #18  
Old 05-20-14, 04:37 PM
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If you have definitely identified the travelers the rest should be fairly easy. At the one switch it sounds like you only have one choice for the common. At the other it sounds like you may need a pigtail to continue power out to other parts of the circuit.
 
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Old 05-21-14, 09:25 AM
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I disconnected all the wires from the two switches and light. Using and extension cord with a working ground and a volt meter I was able to determine that the switch that has 4 wires (the 3 way looking one) has a wire that reads 120v and the light has a 120v. The remaining switch I have discovered what I thought to be a Hot is now reading 0v as I disconnected the light.

I do not know about multiconductors but I believe it is a no. The wires I am dealing with are the old all black, copper middle as thick as pencil lead.

Yes. The switch has two brass and one dark screw. The dark screw, however, was connected to two wires. (This is the switch I mentioned with 4 total wires). The other switch, which I believe had originally failed and something jerry-rigged it with a regular switch, does have on/off on the switch itself.

By trying different wire combinations I was able to identify the two travelers using the continuity setting.

Am I just looking at this all wrong? It is throwing me off that there seems to be no common, but two hots, and am having trouble picturing how the pigtail circuitry works. Am I showing my ignorance?
 

Last edited by Andrew Engle; 05-21-14 at 10:02 AM.
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Old 05-21-14, 10:04 AM
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Using and extension cord with a working ground and a volt meter I was able to determine that both switches have a wire that reads 120v.
Only one of the two switches should have a 120 volts going to the common. Therefore in one of those switches the wire that reads 120 volts is not the common. The comon at that switch will show continuity to the black wire at the light.

How many wires at the light? Using a volt meter set to ohms and a long wire determine if one or more of the wires at the light show continuity to one of the wires in one of the switch boxes. Wires must be disconnected.
 
  #21  
Old 05-22-14, 07:28 AM
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I had edited my post. I disconnected the light and there is a hot in the light. The hot I believed to be in the switch with three wires is no longer hot so that must be the common to the light.
 
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Old 05-22-14, 08:45 AM
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Just to be sure I understand at the light you have two cables. One cable is hot. The other cable is not hot.?
 
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Old 05-28-14, 08:50 AM
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Correct! the "other cable" that is not hot is a traveler wire to the switch. That is why I had thought the switch had a hot before disconnecting the light.
 
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Old 05-28-14, 09:01 AM
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Correct! the "other cable" that is not hot is a traveler wire to the switch.
A cable contains at least two wires. Do you mean the two wires are each travelers?

Please tell me in what ways does the diagram below differ from the cables you have at the two switch boxes and the light.

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Last edited by ray2047; 05-28-14 at 10:37 AM.
  #25  
Old 05-30-14, 06:29 AM
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My situation differs from the diagram above in that I don't have "cables". There are two wires at the light, not two cables. The wires are individual and not from the same "cable". There are no "white" wires as in your diagram from cables A and B. If cables A and B were simply the black, it would look like my situation. There are two wires traveling from SB1 to SB2 as depicted but once again the wires I am dealing with are individual and not in the same cable. In addition, at SB1 there are two additional wires, one hot and one that is neither a hot or a traveler. When I connect the hot and unknown wire at SB1, the lights in the surrounding room function at their switches. With the wires disconnected, the surrounding rooms will not light.
 
  #26  
Old 05-30-14, 08:38 AM
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There are two wires at the light, not two cables. The wires are individual and not from the same "cable"
Are you saying your house is wired with individual wire not cables? Up in the attic do you see:

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Does each wire come in to the box individually, each encased in a cloth tube (loom)?

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  #27  
Old 06-10-14, 01:01 PM
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Yes, exactly.

25 Character minimum to say yes.
 
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Old 06-10-14, 01:19 PM
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The way the light was probably connected is no longer code compliant. It isn't worth sorting out in my opinion. It is better to run new cable from the breaker or fuse box.
 
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