Suggestions for a 4-way switch.

[Spork Schivago]

Hi.

We have a light in the dining room. There's currently two switches that control the light. One is by the outside door, that brings you into the room. The other is by the stairs that lead upstairs. Many times, we'll be in the kitchen and want to turn the light on (we come in through the back of the house a lot because we have off-street parking back there).

I've wired three-way switches before, but for this, I think I'm going to need to wire what's called a four-way switch. I've done a little bit of research on them and need to do a good bit more before I attempt the project, but out of curiosity, has anyone got any experience with these four-way switches?

I'm curious as to what would be the best way to hook this up. It'd be on the same wall with the switch that goes to the stair case. This is on the 1st floor and I'll probably have to do something in the basement I figure. Maybe find where the wires come up from the panel box and add a junction there.

Once I familiarize myself with how they work and how to wire one up, I was thinking I could maybe just tie into the junction box and run some new wires for the four way. It's been a very long time since I wired a three-way switch up and I should probably refamiliarize myself with that as well. If I remember correctly, with the three ways, the white (neutral) goes directly to the light, the black (hot) goes to the first switch. Then I think the red and another white go to the second switch, but I think they both act as hot....the second switch gets the red and white connected from the first switch and it has a black (hot) that goes to the light.

It's been a long time since I wired one though so I might be wrong. I'll google it tomorrow. Any suggestions or tips on the four-way?

[Spork Schivago]

Re: Suggestions for a 4-way switch.

I've done a little more research and I don't think this will be that hard. I believe I found the 12-2 coming from the box going to the switch by the stairs. Then I found the 12-3 (I'm assuming it's 12-3, it's a black wire, not the white stuff I'm used to seeing) going from the first switch to the 2nd switch. I think I'm going to have to remove that black wire and buy some 12-3 then just hook it to the first switch by the stairs and to the four-way I install. Then just run it to the 2nd 3-way switch by the front door there, the one that's already installed.

Just need to purchase some 12-3 wire. Because the wire's in the basement, I think I have to use that fancy basement rated UF-B with ground wire. The stuff I've seen is really thick and a bit hard to work with. It's gray in colour, but rated for outdoors and basement areas.

[Spork Schivago]

Re: Suggestions for a 4-way switch.

This might be a bit more work than I realized. I'm looking at these two images that I've just uploaded.

I see with the 3-way, the hot from the source goes to the second switch, but with the 4-way, the way it's connected to the bulb is different. So I'm probably going to have to undo the ceiling fan / light and mess around with the wires up there and maybe I'm going to have to run a new wire all together...

I was hoping I could just not touch the wires from the ceiling fan / light, but I don't think that's the case.

[eccerr0r]

Re: Suggestions for a 4-way switch.

The current system you have a 3 way system. There's a three wire cable that goes between the two 3-way switches. All you really need to do is to splice into that 3-wire cable - just splice the "4-way switch" into the red and white wires, and then you're done.

However this might not be the most convenient topology. If you have access to only one of the switches, you will need 4-conductor wire to connect to the new switch. If you can tap in the wire between the two switches, no special wire is needed. The problem is that the "4 way switch" needs to be "between"... and that 4-wire cable puts it in "between".

Could you make a drawing of your house topology with walls and current position of switches/lights/wire, and where the new switch needs to be? That would make it a bit easier to decide what kind of wire and where...and possibly also reduce the amount of drilling and new wire. If you don't want or can't dig up the old wire and need to extend off an existing switch, that 4-wire is what you'll need.

Oh.. and yeah you could use two 12-2 bundles instead of a 12-4...that works too, of course...

[sofTest]

Re: Suggestions for a 4-way switch.

Why don't you use a contactor and impulse switches?

Edit: Impulse switches can even be wireless.

[Spork Schivago]

Re: Suggestions for a 4-way switch.

The current system you have a 3 way system. There's a three wire cable that goes between the two 3-way switches. All you really need to do is to splice into that 3-wire cable - just splice the "4-way switch" into the red and white wires, and then you're done.

However this might not be the most convenient topology. If you have access to only one of the switches, you will need 4-conductor wire to connect to the new switch. If you can tap in the wire between the two switches, no special wire is needed. The problem is that the "4 way switch" needs to be "between"... and that 4-wire cable puts it in "between".

Could you make a drawing of your house topology with walls and current position of switches/lights/wire, and where the new switch needs to be? That would make it a bit easier to decide what kind of wire and where...and possibly also reduce the amount of drilling and new wire. If you don't want or can't dig up the old wire and need to extend off an existing switch, that 4-wire is what you'll need.

Oh.. and yeah you could use two 12-2 bundles instead of a 12-4...that works too, of course...

Thank you for the response. I was going to use 12/3 (with ground). That's what we call the red / black / white / bare wire (3, not 4). Is that not right?

I will get the drawing, I need to make one anyway to understand how the previous owners wired everything up. Thankfully, I have fairly easy access to all the wires (except the wire that goes directly to the light).

After thinking about it a bit more, I was thinking I would have to move the 3-way (what I call switch two) to where I want the new switch and add the 4-way to where switch two was.

I think with a drawing, it'll become more clear to us.

[Spork Schivago]

Re: Suggestions for a 4-way switch.

Why don't you use a contactor and impulse switches?

Edit: Impulse switches can even be wireless.

We've already done work in some of the other rooms (because of short funding, we save money, do a room, save money, do another room). We're trying to have the same style throughout the entire house for receptacles and light switches. We decided to go for the Leviton Renu selection of switches and receptacles. I'm not familiar with a contactor, even though I read the link you sent me. I've also googled the term and saw some products.

From what I've found, I'm not really sure how this would help. It doesn't appear to be a switch, not like the kind we're looking for. Do you mean still purchase the Leviton Renu switch and use a contactor instead of just wiring a 4-way switch in?

[Spork Schivago]

Re: Suggestions for a 4-way switch.

Here's a crude drawing that I did. There's two drawings. The first is a layout of the dining room. Where there's a cap, that's a doorway to another room (I've labeled them). I drew little black boxes for where the switches are. There's three switches by the mudroom door that control various things. One of those switches is the 3-way switch that controls the dining room light.

There's a switch by the stairs that lead upstairs. That's a three-way as well.

I can see how the switches are wired, but with switch #2, there's a Romex 12/2 that goes up the wall. I cannot tell exactly where the wires go without taking the wall down, but one goes to the light. Not sure where the "source" is coming from.

Also, things aren't wired properly. There's metal workman's boxes, which I don't like. The switch by the stairs has a ground wire that just connects to the screw that holds the switch into the workman's box.

The switch by the mudroom actually just has the ground wires tied together with a wirenut. We've seen this in other places of the house and fixed them. For some reason, most of the switches / receptacles just don't have the bare ground hooked up. The bare ground is always in the workman's box, and the receptacles that I've looked at so far have a place to hook the ground up to, it's just the previous owner never physically hooked them up. They just use a wirenut to connect the ground coming into the workman's box to the ground going out of the workman's box. I think that's wrong.

[Spork Schivago]

Re: Suggestions for a 4-way switch.

I was thinking the easiest, once I figure out where the wires that leave switch #2 go, would be to move switch #1 to where we want the new switch and then add the 4-way to where switch #1 was...you know, put it in the middle, so to speak.

From the drawings in post #3 ( https://www.badcaps.net/forum/showpo...20&postcount=3 ), it just doesn't seem like this 3-way switch is wired properly at all, does it? Look at the pic for the 3-way in post #3 and see how they wire the traveler wire. Then see how it's wired in my house.

[Spork Schivago]

Re: Suggestions for a 4-way switch.

I have to go buy a cheap replacement 3-way. When I removed the one by the mudroom, I heard something snap. I didn't think much of it, but now, when I turn the light on from that switch, I cannot turn it off from the other switch. I think the switch is actually broken now. I didn't undo any wires or anything, just left them the way they were.

But I'm going to kill the juice to the entire house, just to be safe, go buy a replacement, switch them out, double check everything, restore the power, and go from there.

I'll be back later. Don't need the house catching fire or anything!!!

[Spork Schivago]

Re: Suggestions for a 4-way switch.

We're back up and running. I bought 50 foot of a 12-gauge solid copper and a regular 15-amp 3-way Leviton switch from Home Depot. I bought some wire nuts as well. I stripped the 12-gauge wire I bought and ran what I call a pigtail from the wire nutted ground wires to the new switch and then just hooked it up the way it was hooked up.

It worked. I want to buy one of those non-contact voltage detectors. I figure I'll pull the wires that lead away from the switch, cap them with a wire nut, and then use the non-contact voltage detector to see which one is the source, just to get a better idea of how this is wired. Right now, it just doesn't make sense to me. I don't see where the juice is coming in. I figure maybe it's somewhere behind the drywall.

[eccerr0r]

Re: Suggestions for a 4-way switch.

The wiring must be correct, well, it does work?

If you replace switch #1 by the stairs with the 4-way and put the displaced 3-way into the kitchen, yeah, should be able to use a 3-conductor wire. You'll need to pass black to the new switch location, else the two sets of red/white goes to the 4-way now in the middle.

So there's two bundles of wires that goes to the switch#2, right? One 12-2 where black goes to the switch and white goes to a wire nut to black of the 12-3? That sort of makes sense but indeed confusing... Then the suspicion is that box used to be a 2-way switch that was added on to a 3-way perhaps? If this is the case the power must be going straight to the light and that 12-2 is the control cable?

[Spork Schivago]

Re: Suggestions for a 4-way switch.

The wiring must be correct, well, it does work?

If you replace switch #1 by the stairs with the 4-way and put the displaced 3-way into the kitchen, yeah, should be able to use a 3-conductor wire. You'll need to pass black to the new switch location, else the two sets of red/white goes to the 4-way now in the middle.

Do you think you could modify my PNG image to show how the third switch would be wired?

So there's two bundles of wires that goes to the switch#2, right? One 12-2 where black goes to the switch and white goes to a wire nut to black of the 12-3?

That is correct. That one 12/2, that somehow goes to the light. I know this because I can follow the 12/3 down in the basement. If I buy one of those non-contact voltage detectors, maybe I can make more sense out of it. The 12/3 they used to go between switch #1 and switch #2 is black in colour. In the gang boxes, I can see where the black wire comes up from the basement, into the bottom of both gang boxes. To me, it makes sense that the 12/2 that connects to the switch #2 and leaves from the top of the gang box goes towards the light. I just can't figure out where the actual juice comes from. Could they have the 120VAC wired directly to the light and it's always there, but the switches just control the neutral? Is that possible?

That sort of makes sense but indeed confusing... Then the suspicion is that box used to be a 2-way switch that was added on to a 3-way perhaps? If this is the case the power must be going straight to the light and that 12-2 is the control cable?

I think this just answered my question above. But just to be certain, what do you mean by a control cable? Does that mean it's just controlling the neutral? Your hypothesis there might be correct, with it originally being a 2-way switch and being modified to a 3-way. That could explain why it's not wired like the drawing. But this will make it harder for me to add a 4-way. I can follow the diagrams I find online, but this isn't wired according to the diagrams I found.

I've read how the 3-way's work, but I still don't fully understand the physical switches and what connection does what. I follow the drawings and diagrams that I find on-line, but I need to find a document that explains what the terminals on the 3-way are. I think it'll make more sense to me once I figure that out. I'll do the research right now, just got the baby down for a nap.

Thanks!

[Spork Schivago]

Re: Suggestions for a 4-way switch.

I might have this understood now. I'm uploading another picture I've made.

On-line, I found a picture where they label the "common" wire, but if I'm understanding it correctly, it's not necessarily a common.

In my picture, if we take switch number one, the terminal on the right hand side (where the red wire connects), if we switch switch #1 up, it will be like connecting the red wire on switch #1 to the black wire on switch #1, right? If we switch it down, it'd be like connecting the red wire on switch #1 to the white wire on switch #1.

Looking at the diagram, I'm thinking if I were to take that 12/2 that goes into the gang box on switch #2 and just remove all the 3-way switches and wire those two wires together directly, the light would be on. Is that correct?

I'm still a little confused those. Take a look at switch #2. If that's down, that would connect the white wire on switch #2 to the red wire on switch #2, right? If so, I don't see how switch #1 could control the light at all, if switch #2 is in the down position....

I've uploaded another diagram that I think explains how the switches actually work. But if this second diagram is true, I don't understand how the light turns on if switch #2 is in the down position, regardless of what position switch #1 is in.

[Spork Schivago]

Re: Suggestions for a 4-way switch.

I believe I figured it out! I tore the old broken one apart to see how it works and now it makes sense to me. In our house, the light is on only if both switches are down or both switches are up.

This is how the connections are made if it's in the up or down position. Now the wiring diagram I look at of how it's wired makes since.

My wife is going to go purchase a non-contact voltage detector, but if I understand this, that 12/2 that leaves the top of the gang box on switch #2 is the secret. One of the wires goes directly to the light and the other one goes to the breaker (either a neutral or a hot wire). The wire that's connected to the light always is the opposite of whatever the wire is that goes to the breaker.

If the switch is controlling the hot wire that goes to the light, then if I turn off the light, I should be able to use that non-contact voltage detector to determine if it's the black wire or the white wire on the 12/2. Now I just gotta find a torn apart image of the 4-way switches to see how they work.

[eccerr0r]

Re: Suggestions for a 4-way switch.

Yeah, the 3-way switches are SPDT switches.
The 4-way switches are DPDT switches wired as crossover/straightthrough switch.

What I meant by a "control cable" is a cable that you could just connect a SPST switch and it would turn on the light, versus putting a SPST switch there and blow your whole wiring system (meaning, you should put an outlet there).

Ok here's an even more crude picture of what to do... and oh i think i drew the internal diagram of the 4-way switch diagram wrong... should be rotated 90 degrees

[Spork Schivago]

Re: Suggestions for a 4-way switch.

Does this seem right to you guys?

If this looks right, I think I'm going to have to run the black wire that leaves switch #3 and goes to the switch #2's gang box (to go to the light), all the way through...starting at switch #2, running it to the 4-way but not hooking it to the four-way, using a wire nut or something, and then running it to switch #3 there

[Spork Schivago]

Re: Suggestions for a 4-way switch.

Yeah, the 3-way switches are SPDT switches.
The 4-way switches are DPDT switches wired as crossover/straightthrough switch.

What I meant by a "control cable" is a cable that you could just connect a SPST switch and it would turn on the light, versus putting a SPST switch there and blow your whole wiring system (meaning, you should put an outlet there).

Ok here's an even more crude picture of what to do... and oh i think i drew the internal diagram of the 4-way switch diagram wrong... should be rotated 90 degrees

Oh my gosh! I didn't refresh the page and read your post until after I uploaded my image, but if I'm reading yours correctly, I think I designed it the same way you did, that means I understand it!!! Unless I'm reading yours wrong and I drew mine differently, but from what I can tell, they're the same.

I almost got the 4-ways completely figured out, but I think once my wife picks up a cheap one, the multimeter on continuity mode will fill in the remaining gaps.

I don't understand the statement about the SPST and blowing the system without a receptacle. I understand that I don't need a receptacle for my system, but I don't see how a receptacle would matter. I guess I'm having a hard time visualizing how it could be wired where it'd blow a system unless a receptacle was added...

I do appreciate you guys taking the time and helping me understand this. It's definitely been a lot of fun and a great learning experience. I've talked to my neighbor who works at Corning Appliance. They do stuff like installing switches and furnaces and cold-air returns and ductwork and all that. He says he's wired 3-way switches before but never understood how they worked, he just followed diagrams he found online. I've talked to a few people who have said similar things. It's nice when you actually realize how something works the way it does and I think because I learned how it actually worked, I was able to figure out how to add a 4-way switch without needing to look at any diagrams that showed how it was supposed to be wired.

[eccerr0r]

Re: Suggestions for a 4-way switch.

yeah it looks like yours is the same, should work.

About the SPST (the regular kind) switch - Well, when you short two wires together, you can either complete a circuit or completely destroy your house... I call the former a "control" circuit, and the latter a "power" circuit which should be connected to an receptacle...

[Uniballer]

Re: Suggestions for a 4-way switch.

I might be misinterpreting what you are trying to get across, but this does not look to me like the right way to do it (i.e. safe and compliant with the NEC). You should be able to keep the grounded current carrying conductor (aka neutral) from ever being switched with the other conductors.

Check out this link: How to wire a 4-way switch