How do you wire a light with 2 separate switches on different walls?

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zannej

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Thanks. I sort of wonder if some of the wires have been chewed. When I did a test on some of the plugs the tester thingy indicated there was no ground on some. Indicated reversed poles on others as well as no ground. I think the people who did the house wired most everything with 2 wires & no ground. We don't even have a grounding rod as far as I know.
 

Guzzle

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"the tester thingy" will lie to you & so will the non-contact voltage testers. :(
 

bud16415

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I think the plethora of diagrams and pictorials of 3-way switch wiring just add to the frustration. Also calling switchable conductors carriers or travellers just adds confusion. What I picture in my mind when working on a 3-way circuit is a circuit similar to this pic with whatever wire colors happen to be present. View attachment 27180
This thread is about educating someone as to how a 3way switch works and it seems Eddie_T post #13 should be studied closer by those trying to grasp the concept. This is the same sketch that was used 50 some years ago to explain the concept to me. There are a million pictorials that show switches with wires running around that don’t hammer home the point like this simple electric schematic.



The two switches never have an open position rather they are selector switches going to A or B. When you put two together it becomes obvious how if the path is open by one down and one up switching ether one will complete the circuit.



If you are having trouble understanding this take a few minutes and really look at this.

As a side note on my truck I put a light in the back to light up the cap. I wired it as a 3way with 12v toggle switches. I could turn on the cap light from inside the truck and look thru the rear window at night or if I was outside I could open the cap and turn on the light. I would forget to turn it off and didn’t have to get out of the truck to turn it off. I had a guy with me that fixes cars and he saw me do that and said that’s cool what kind of a relay did you use? I said no relay just two switches. He told me that was impossible. 😮
 
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Guzzle

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If I can't do it, it must be impossible! :D:D

I knew a kid in high school who thought that. But I'm sure I've met other people like that, they just didn't say it out loud.
 

Eddie_T

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A lot of people think electricity is seeking the shortest path to ground. In reality it seeks nothing but will follow any and all paths back to the source.
 

Guzzle

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With more than one path, the most current will flow thru the path of least resistance.
 

Eddie_T

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I suspect many household shocks are phantom shocks unless one happens to touch a hot and neutral or ground. I say this because our floors are not conductive and most of us wear these big ugly thick soled shoes from China that should serve as good insulators.

My non-contact siffer beeps o the brass of my lamp but my neon tester shows nothing.
 
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zannej

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My personal philosophy is that anything is possible, but some things are highly improbable. Sounds like the naysayer just didn't know how to wire the two switches without a relay so it didn't register as true. Some people have an inflated sense of their knowledge skills-- Dunning-Kruger.

This has been an interesting discussion in how electrical works though. I wish I remembered more from high school electronics. I've passed info on to my friend and hope he will make good use of it.
 

ajaynejr

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I think the plethora of diagrams and pictorials of 3-way switch wiring just add to the frustration.
So long as myriads of different and accepted wiring methods exist in actual circuits in buildings, etc. there will be the desire to mention them in wiring handbooks and other literature.

Alternatively someone might simplify his/her response to a question by citing just one method or solution (his/her preferred method). Once many years ago I was doing some wiring and an inspector said that what I did for one 3 way switch setup was "allowable but not kosher." I remember that one; I brought power to the light fixture box and had the travelers, spliced within that box, go from there down to the two respective switches. The wiring handbook I had depicted that method.

Sounds like the naysayer just didn't know how to wire the two switches without a relay ...
Or maybe the naysayer did not have the right kind (double throw) of switches.
 
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Eddie_T

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I mainly don't like pictorials, I prefer schematics or wiring diagrams. I also had a clever little book (no pictorials) that showed all ways to wire lights and fixtures.
 

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