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

[zannej]

My friend was asking me to ask here if anyone could explain how to wire a light that uses two separate switches on different walls. I have some in my house like that, but my electrical is all wonky so it's a poor example for study. My friend's grandfather's contractors didn't hook the wiring back up to the light & switches after they disconnected stuff and fixed things up. The old man is super aggravating so I doubt they are willing to come back.
So, my friend was asking as he's never done that sort of wiring before. Any diagrams, descriptions, video links, etc would be helpful.

 

[Snoonyb]

Gazillions, 3 way switches; wiring 3 way switches

 

[Snoonyb]

Gazillions, 3 way switches;wiring 3 way switches

 

[zannej]

So it's called a 3-way switch? Thanks! I'm sending some of those over to my friend.

Requires a 3-way switch? With 14/4 with ground?

Friend just told me the contractors hung the doors the wrong way, left holes around outlets and switches on the drywall (that are too big for coverage from wall plates). Hot mess.

 

[Sparky617]

A three way has two switches, a four-way has 3 or more switches.

 

[zannej]

Thanks. Apparently the contractors only put in basic cheap single pole switches that are not 3-way & there were only 2 wires.

As an aside, is there a low voltage device that can be used to power switches (temporarily) to test the connections to make sure they are done right?

 

[Sparky617]

In order to conventionally control the lights from 2 or more locations requires 14/3 run between the switches. There may be a wireless smart switch option out there that could accomplish the same thing.

 

[zannej]

Thanks, Sparky! I passed that info on to him. He wires vehicles, video games, computers, and he's done basic electrical on houses, but he wasn't sure how the 3-way switch worked (or what it was called). He did know more about this stuff before his traumatic brain injury but he forgot a lot of things.

 

[Guzzle]

As an aside, is there a low voltage device that can be used to power switches (temporarily) to test the connections to make sure they are done right?

A VOM.
For long distances between switches you can use any extension cord as a test lead.

 

[Snoonyb]

Thanks, Sparky! I passed that info on to him. He wires vehicles, video games, computers, and he's done basic electrical on houses, but he wasn't sure how the 3-way switch worked (or what it was called). He did know more about this stuff before his traumatic brain injury but he forgot a lot of things.

In the past I've used the , "in fixture", remotes for control;ing ceiling fans, to control the fixture. It may be a bit pricey, but eliminates a lot of excess trial and error.

 

[Guzzle]

In the past I've used the , "in fixture", remotes for control;ing ceiling fans, to control the fixture. It may be a bit pricey, but eliminates a lot of excess trial and error.

In general, more complexity = higher failure rate, but wiring 3 way switches can be very frustrating.

 

[Eddie_T]

I guess I am locked into X-10. I have been using them for over 25 years. I have a clock timer that turns LR and den lamps on/off when I am home or away. Some lights I just leave on all waking hours kitchen fluorescents and bath LEDs. The others the switch is by the door.

 

[Eddie_T]

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.

 

[zannej]

My friend's grandfather is *super* cheap. He wants things done for him for free and will want everything at someone else's expense. Apparently he fired the people his insurance company recommended because he didn't like how much they wanted to charge and he hired some local yokels who are probably not licensed. So they did a terrible job. The old man is not smart so whatever solution is in place has to be simple. He's too dumb to figure out how to use any sort of device other than a wall switch. I'm thinking the rocker style might be better for him.

 

[Guzzle]

And if you move the lamp to the hot wire in the diagram, either diagram covers virtually all configs.
To find out if the lamp is in series with the hot, I put another identical (incandescent) lamp down to the neutral line or ground. Then both lamps glow at 60vac. . . no drama, no fear.

 

[BuzzLOL]

I wouldn't want the light fixture wired to the always hot side of the 3-way circuit... using the switches to supply the neutral/ground... although that is done in 12 volt automotive circuits...

 

[Sparky617]

I wouldn't want the light fixture wired to the always hot side of the 3-way circuit... using the switches to supply the neutral/ground... although that is done in 12 volt automotive circuits...

You don't switch the neutral in 120v wiring. The switch is hot, with the hot changing which traveler is hot depending on the switch position. If the neutral is switched the shell of the light socket is hot instead of the tab at the bottom of the socket.

 

[zannej]

I wonder if the neutral is switched on many of my fixtures bc it seems the sockets get hot. Right now I can't figure out why my lights in the living room burn out or are dim. I'm guessing we need a new switch or wires are damaged. The new LED bulbs were bright for awhile but now they are dim and flicker. The fan works ok though.

 

[Guzzle]

I wonder if the neutral is switched on many of my fixtures bc it seems the sockets get hot. Right now I can't figure out why my lights in the living room burn out or are dim. I'm guessing we need a new switch or wires are damaged. The new LED bulbs were bright for awhile but now they are dim and flicker. The fan works ok though.

A bad neutral connection at the main panel will put overvoltage or undervoltage on half your house.

 

[Eddie_T]

Electrical fires are all to common. If lights are dimming or popping I would be running for my VOM. I think all homeowners should have a course in basic electricity and VOM troubleshooting. Maybe there's a youtube presentation that could be of help to homeowners. Most seem to be too slow, too boring or a bit misleading. I don't have the time or patience to review them in search of a concise presentation to recommend, maybe that's something we should all keep in mind as we surf the web.