4-Way Wiring Help Using Alternative Configuration

Hello Inovelli Community - I am seeking advice going from my 4 way dumb switches to smart setup. Wiring setup is not ideal but know we can make it work some way. Due to the setup, I’m thinking I may have to reduce to a 3-way switch but would like to know everyone’s thoughts with this alternative wiring configuration. Wiring details:

Line in at A (see pictures below)
Load at C

A - 3- way (Line in, 2 travelers, no ground/neutral :frowning: )
B - 4 Way (4 travelers, has ground and neutral)
C - 3 way (Load, 2 travelers, has ground and neutral)

Ideally, I want a red series dimmer at C. In order for this to work, I routed the hot line in from A to B to C using one of it’s travelers to move the hot line to C. This leaves 1 free traveler at A as seen in the picture.

What is my best option as far as keeping dumb switches at A and B or replacing them with smart or Aux switches?

Options I am considering (maybe there are other options):
Add a second red series to B and tap off the line and neutral, both with pigtails. This switch would act using z-wave association or as a scene controller with switch C.
Add a 3 way to B? I was having trouble making this work without losing power to C every time I switched B. Maybe I was wiring incorrectly?

In any case, I’m not sure if I can still have a switch at A due to the wiring configuration? In this case I would put a blank plate over A.
On second thought: Suppose I fed a neutral back to A using the remaining traveler and then pigtail off the line. Doing so would allow for remote z-wave I believe, but maybe this isn’t my best option.

Thanks everyone!

Trying to figure out what you have going on here. It looks like you installed an Inovelli in C, but what’s up with the other two boxes? Did you remove switches or did this take place earlier?

Let’s do this one step at a time and focus on C. For future reference, try to post individual pics. I know you can’t initially, so what you posted is OK, but you can’t zoom in as far on a multiple pic shot. Also, fully pull everything out so it’s easy to see what’s going on.

So Romex-wise, what is coming into box C? I’m guessing a 3-wire and a 2-wire? Disconnect the 2 wire and then using a meter, check for voltage across the black and white. Don’t want anything connected to the two conductors to avoid confusion. Let us know if that 2-wire Romex is constantly hot.


Thanks for the quick reply. Right now at C I have an Inovelli on/off for testing until I get another Red series Dimmer. At ‘A’ and ‘B’, I removed those switches. ‘A’ used to be the 3-way dimmer control and ‘B’ was the 4-way switch. ‘C’ used to be a dumb 3-way.

Coming in to ‘C’ (when all the wires are disconnected): 2 travelers from ‘B’, load (lights), neutral, and ground. I know this is a terrible picture and will get you a better one showing the Romex to help clear things up when I get home. I can confirm there is NO natural constant hot in ‘C’. The only constant hot comes in at ‘A’. What you see in the pictures - I legged the hot over from A thru B using the travelers to give ‘C’ a constant hot since this is where I need the smart switch and this box has a neutral.

To re-iterate, here is what is at each box (when all the wires are disconnected):

A - Hot Line in, 2 travelers to ‘B’
B - 2 travelers from ‘A’ and 2 from ‘C’ , has ground and neutral
C - Load to lights, 2 travelers to ‘B’, has ground and neutral

Hope this helps clear any confusion.

Thank you!

Ok, thanks for clarifying.

So A has a 2-wire and a 3-wire Romex. The 2-wire, when you measure unconnected to anything is a constant 120V across the black and white.

So B has two 3-wire Romex.

C has one 3-wire and one 2-wire Romex. If the 2-wire isn’t hot, then I think you are correct going to the lights.

If I have that right, I understand that you want the Inovelli at C. Presently you are sending the hot from A via B to C by connecting the hots and neutrals.

I think you can use Auxs or Inovellis in the other two. Since you have a neutral installation in C, then the Auxs just need ONE traveler and a neutral. This diagram isn’t exact to your situation, but it shows what I’m describing:

If you want to use 3 Inovellis, then you just need a hot and a neutral in A and B. This configuration does not use a Romex conductor for signaling, so you will have to create device-to-device associations.


To clarify a little further - oddly I cannot see Romex in ‘A’ but it consists of 1 black hot and the other 2 black and white I’ve tested and proven to be travelers to B. There is in fact NO neutral at ‘A’ . I was only able to detect the hot wire by using an extension cord to a grounding outlet with a volt meter (after lots of head scratching :laughing:). I suppose I can feed a neutral from ‘B’ to ‘A’ on the remaining traveler to connect to an Inovelli pig tailed to the hot wire in ‘A’ and use device to device association as you suggested using Hubitat. I will be home soon and provide you with better pictures of the Romex in C if that helps any but I am almost confident you are right C has one 3-wire and one 2-wire Romex.


Ok, so right now we’re just concerned with Romex cables. Travelers are individual conductors.

So I’m trying to understand A. There is a single black and a blank and white Romex? Please take a picture from the front with everything pulled out. If your electrician ran out of 3-wire you could in theory use two 2-wires, but I’d still expect to see the unused white.

Pics for B too, please.


Here you are with the close up of A, B, and C. As you can see in A, I’ve tied 1 of the two travelers to the hot. The white is in fact a traveler.

Thanks for you help understanding this!

Thanks, but I don’t know if I’m understanding this or not, lol.

So you have two 3-wire in box B that I would expect. But one of those 3-wire should be going to A. So if this was normal, in Box A you’d have a black, red and white in one 3-wire, which you don’t.

How long have you been in this house? Could A have been moved and maybe that 3-wire got routed to a junction box and then one and a half 2-wires used to go to the new location?

I know that you think the source of your hot is in A, but I’m not convinced that is the source. Just because it’s hot now doesn’t mean it’s the Line, particularly since that black conductor isn’t accompanied by a neutral. If this box really was the Line, i.e. the source of the hot, then the neutral would be passed down the line to the next box.

You still haven’t ruled out power to the light first. Go to C and disconnect the 2-wire (which you believe is going to the lights). With those wires completely disconnected, using a meter, test across the black and white and see if you have 120V. If you don’t, test between the black and the bare ground and the white and bare ground to see if either of those have 120V.

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One other test . . while you have the 2-wire in box C completely disconnected, check the black in Box A to see if it’s still hot. I would hope your box is grounded, so you MIGHT be able to test between the black and the metal box.

Hey Bry,

Regardless of color, 2 of the wires do go from box B back to box A. One is black and one is white. The remaining black is what I am saying is the hot line in. I am not sure where the color change occurs from B to A. To add perspective, it may be worth noting that these switches are across the room from each other with the ceiling track lights in between.

I have been in the house for over 5 years. It is a 1999 and was working normal with “dumb” switches, so I don’t believe any wiring was tampered. I see no signs of A moving.

I have previously performed the test you are mentioning with every single wire disconnected all at once for all 3 switches. I was stumped because there was absolutely NO hot to be found. Lots of head scratching later… I used an extension cord from a nearby outlet to provide a ground to switch A and check voltage for each and every wire. The one box A black wire was the ONLY place with one wire I found 120. I assure you I checked every wire in C to neutral and ground and there was no voltage.

I know, confusing wiring.


With regards to the second reply: Yes, the single black in box A is hot while every single wire at all other boxes is disconnected and capped. However, I have to use an extension cord to seek ground at another outlet and read the 120v on the box A black wire. Box A is not grounded :thinking:

Thinking about this more, I do have the option to connect the white in box A which is really a red in box B. Connect box B red to neutral will provide box A white with a neutral. This would result in box A having hot, traveler, neutral. In this case, I’m not sure if I could still have a switch at box B.

Well, I’ve seen a lot of wacky stuff, but I have to admit that I can’t figure this one out. We know that three-way circuits have 3-wire Romex between them. You have two 3-wires in the B box. One of the should be going to A. But instead in A you don’t even have Romex. Instead you have three THHN/THWN conductors and they’re not even color matched to the 3-wire. (The NEC requires THHN/THWN to be run in conduit, BTW.)

I know you said the lights are physically between the two switches, but the C box has a 2-wire Romex that you are convinced goes to the lights.

Then there is the hot without a neutral, in a metal box that apparently isn’t grounded. An if that really is the hot feed, the only reason 2 wires going out would work is because the neutral isn’t being sent. This means . . . you guessed it . . the neutral is being picked up sonewhere else. Which of course makes you wonder if it’s on the same circuit. If it’s not, there’s another issue.

My first inclination is to recommend that you hire an electrician to diagnose what you have going and fix it. I could be wrong, as it’s hard to diagnose remotely sometimes, but this smack of a lot of things wrong. Just because it works doesn’t mean it’s illegal or safe.

Insofar as wiring Inovellis, I’m sorry Brandon but I have to beg out.

I’m curious to see what @JohnRob or @harjms think of this.

If anything you confirmed that I am not alone in this confusion.

Worst case, I resort to leaving the smart switch only at C (how I have it wired bringing over the hot via traveler) and cover A and B. Or like you said hire an electrician who will tell me I either completely missed something or major re-wiring would have to be done. In that case, I would settle for just a smart at C.


@Bry - This is interesting. I wonder if there is a junction box hidden behind the plaster that someone wanted to move the original box to another location and used THHN wire vs ROMEX…They probably bought two rolls (blk and wht) and just doubled up on the BLK to act as the RED. Normally, when I see metal boxes, I can see the conduit end screwed into the metal box. I don’t see this here :flushed:

I was almost thinking LINE came into box C, B is 4 way, and LOAD is in box A, with a neutral at the light already. That way, the Load is one of the BLKs, and the other BLK and WHT are the travelers, but then it doesn’t match Box B since there are B/W/R in there. There has to be a junction box inline.

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It would make so much more sense if the line started at C with the load at A as you described. I wonder if it’s worth getting ladder and peaking into the light junction to see what’s hiding under there.

@daytonalott - If you have a multimeter, I’d start going through the wiring and checking continuity at all the locations (with power off). That way you can check which wire is tied to each wire. I have a spool of 500 ft 28 AWG green wire to hit all my boxes for continuity checks, but you may not have it. That way I can loop between multiple boxes or use it as an extended test lead.

@daytonalott - Definitely worth looking into. Hopefully you’ll see Box A leads in one of the light junction boxes. Then you can ring each one to figure out which line is what. Just weird there’s no RED in Box A. That’s throwing me off.

I thought about doing this and I may have enough wire to do this. I just thought I could narrow it down by connecting wires to hot and using deductive reasoning with a volt meter to figure out what wires go where.

Ahh…I think the electrician outsmarted us on this one…Although, I’m sure it’s easy to follow if all the walls were removed and we’ll all be like “OHHHH that’s what he or she was trying to do”…