Stumped by this particular 3-way switch

Devices & Integrations Device Ideas
1

Done plenty of three ways before but this one is stumping me.I am at a bit of a loss, how to wire a Z-wave switch (and auxiliary) to replace the current 3 way. I have a hallway with two sets of recessed lights (one for art, one for general lighting). We want to automate one set (Circuit 2).

Both sets of lights have 3way layout with the switches in the same boxes on either end of the hall.

To simplify I have included a drawing of what each box is set up currently. Anyone have any leads on this or a process to figure it out? Not that it matters, but I am installing Dragon Z-wave plus switches.

Hall Wiring_01.jpg2550×4200 400 KB

2

It was pointed out to me I should say the following:

The two large blue squares are each of the junction boxes where the switches are located.

The lights are buried in the attic insulation hence I can not diagram the circuit, only show what the switch boxes hold.

3

Jon,
I’m having a bit of trouble understanding your diagram, but hope this helps . . .

The first thing to know is that the Traveler (Red) wire in the Dragon Tech works very differently than in a typical 3-way setup. For the Dragon Tech switches, the Red wire (as well as the Remote switch) NEVER have main power passing through them regardless of the state of the system (this is very different from a regular 3-way installation). Instead, the Red wire acts as some sort of a signal carrying wire to the Dimmer, but never carries main power to the load. The Black wire is the power carrying wire.

So, for typical setup . . .

I assume there are two gang boxes with “typical” wiring. That is, Box 1 has a first cable with a “hot” Black/White pair from the fuse box (call them B1 and W1), and a second cable with Black/White/Red wires (B2, W2, R2) running between Box 1 and Box 2. Box 2 has the incoming Black/White/Red (B2, W2, R2) from Box 1 and a third cable with a Black/White (B3, W3) to the load (lights). I haven’t mentioned neutrals, but those are handled in a typical fashion – all joined together with connections to the neutral grounding screws.

What you do (obviously with main power off!) is . . .

At Box 1:
W1 and W2 are both connected to the Neutral screw of the Remote switch. Effectively, this is a typical “join all white wires” setup.

The HOT wire B1 and B2 are then simply connected together with a wire cap. B1 is not connected to anything else at Box 1. Effectively, this means that the B2 entering Box 2 from Box 1 just acts as a connection back to the fuse box and is always HOT when the circuit breaker is on.

At Box 1, traveler R2 is connected to the Traveler screw on the Remote switch.

At Box 2.
W2 and W3 are both connected to the Neutral screw on the Dimmer. Again, this is effectively a “joint all neutral” wires connection.

Traveler wire R2 from Box 1 is connected to the “Traveler” screw on the Dimmer. Thus R2 only goes between the Dimmer and the Remote switch.

B2, which is HOT, is connected to the Line screw on the Dimmer.

B3, to the lights, is connected to the Load screw on the dimmer.

4

Yea my picture wasn’t clear as I didn’t label it well. I have someone helping me on cocoontech right now and I think we have it figured out.

Here is his best guess as to how it has to be wired to be working as is.

gallery_19420_147_17547.jpg743×941 131 KB

I am going to have to do some funky wiring to get it to work, i.e from the DT100 at location 2, I will use the white to the fixture as the load, and the black traveler to carry neutral to the second box (which turns to white at the fixture). Red stays traveler.

Then tie the location one black wire to neutral in that box. Then I have to mark all the wires appropriately so I can remember WTH I did.

5

Connecting blacks to whites is probably all sorts of code violations, but it may be simpler than you think to wire the switches without doing that.

Remember that all whites in your home should be wired to “common” through some path. So it isn’t really necessary that the physically same white/neutral connects to the Dimmer, Remote, and Load as long as you have some white/neutral connected to each of these and they all trace back to the common bus at the fuse box. I.e., as long as you can bind all whites to each other and the neutral terminals on the Dimmer and Remote, that should resolve the white wire.

As for the Red, it looks like you can run that between the two locations, so you should be able to connnect the Traveler terminals. Finally, put the dimmer in the box where you can connect its LOAD terminal to the fixture HOT (black) wire. Now, as long as there is a HOT wire in that gang box, you can connect that to the dimmer LINE terminal and you should be O.K.

6

Further clarification. I think I now understand your diagram.
Here’s how I read it:
At Location 1 you have a 3-way switch, but you don’t have Main power coming in - i.e., no fuse box connection. Instead, you have a single cable going to the light fixture box. Let’s call the wires from that cable B1, W1, R1.
At Location 2 you have a second cable going to the fixture box and we’ll call those wires B2, W2, R2. You also have power from the fuse box coming into Location 2 and a common neutral, Call them B3/W3.

If this is correct, then . . .
At Location 1, install the Remote. Connect W1 to the Neutral Terminal. Connect R1 to the Traveler Terminal. Cap off the black wire, B1 - it will be unused.

A the Fixture, cap off B1 - remember, it is unused. Connect W1 and W2 to the neutral wire of the light fixture. Thus, binding the neutral wire of the Remote Light Fixture and connecting the neutral back to Location 2 via W2.

This configuration will result in NO HOT connection to Location 1. It only connects Neutral W1 and Traveler R1.

At Location 2, here you will install the dimmer. Connect the Dimmer LOAD terminal to B2. This connects the LOAD terminal to the light fixture and nothing else. Connect the Dimmer Traveler wire to R2. This then makes a Red/traveler wire connection between Dimmer and Remote. Connect the Dimmer Neutral to W2. This then binds the dimmer neutral to the fixture neutral to the remote neutral. The Dimmer neutral should also be connected to another Neutral/White in the Location 2 box. This then binds all the neutral wires together. Finally, find the main power HOT wire at Location 2 and connect it to the Dimmer’s Line terminal.

Effectively, all of the “HOT” connections are in Location 2 with the HOT LOAD connection (B3) going from Location 2 via the Dimmer to the fixture on wire B2. There is then a common neutral between everything, and a traveler that extends all the way between Location 1 and Location 2 and only connects the switches.