Wiring help? 3-way switched outlet

I have a switched outlet that has 2 switches controlling it. I’m not sure if I’m going to be able to use smart switches or not. I guess I could swap it with a smart outlet, but then I have 2 dead switches that I need to drywall over - not exactly what I want to do. The power is coming from the breaker to the outlet, and then from there to the switches.

I could get hot and neutral to the first switch, but i have no way of getting the load back down to the outlet from there. Running additional romex isn’t really an option. If I were to use a relay, wouldn’t that also render the existing switches basically useless? And if the switch is off, the device is offline?

Thanks for any tips you have!

You can certainly use smart switches for this general use case by wiring a master switch to the outlet and then using an auxiliary switch for the other switch position that communicates by radio to the master switch. So it essentially becomes a remote on the wall controlling the master switch rather than controlling the outlet directly. This is quite a common configuration for people who are adding an additional auxiliary switch where they didn’t have one before, but it should also work for you. In fact, the auxiliary could even be battery-operated.

The exact details will depend on the specific brand and model of the master switch that you choose.

You didn’t say, but do you have a neutral at the switch box for switch one? most smart switches require one, although not all do.

I will leave further discussion of the exact wiring details to people who know what they are talking about on that subject. :wink: ( I’m a network engineer. I’m good on device specifications, but I leave the wiring to the electricians.)

So, there is a white wire, but it’s being used for purposes other than neutral in the current setup. The challenge I have with most smart switches is that they need line, load, and neutral. In my setup, there are only two wires running between the switch and the outlet, so if I pass the hot wire onto the smart switch, i have no way to pass the load back down to the outlet. At least that’s how the rest of my switches are wired.

I purchased the leviton decora switches for this, but I don’t think they will work with power going to the outlet first. I also have a zooz (ZEN26) switch, though when I emailed zooz customer service, they told me that the ZEN26 is only rated for 8amps and using it to control a 15 amp outlet would not be supported. They never actually answered if I could technically wire it in, though :slight_smile:

In the United States, in most places wire color is not mandated by code with a few exceptions, so you can never go by the color of the wire. You have to map the circuits to see what they actually are.

And wiring for smart switches is different than wiring for dumb switches, so that becomes a separate issue as well.

Zooz was quite correct that US code in most locations requires that an outlet be able to handle 15 A but it is lower for light switches, so if a switch is only rated for lights you may not be able to use it to control an outlet. But there are switches which are also rated for 15 A. Just as an example, the following Leviton Z wave switch is rated for 15 A. It does require a neutral, though.

I can’t comment on the specific wiring question, as I said, I leave that to the electricians.

As @JDRoberts said, wiring smart switches for 3-way is generally different from wiring dumb switches. And each brand of smart switches works a bit differently. Most brands require a specific auxiliary switch to work with their smart switches.

The Leviton model JD mentioned is one of the few that will support 15amps which is mandatory for an outlet.

That model smart switch has to be paired with a Leviton DD0SR-DLZ for 3-way. The published wiring diagram requires that

  • the DZ15S-1BZ must go in a box with load, neutral, and two traveler wires. One traveler will carry line/hot, the other interconnects the two switches.
  • The DD0SR-DLZ has to have line, neutral, and the other end of the two travelers.

Leviton is one of the more complex smart switches to wire for 3-way.

The Zooz ZEN26 can work with your existing dumb switch but you have to have line, load and neutral.

I don’t know if GE/Jasco has a smart switch rated for 15 amps. They require a specific aux switch model but the wiring is very simple, again provided you have line, load, and neutral in the primary box.

The go-to guy for tricky wiring problems here is Michael @ritchierich

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It’s true that if you are going to use physical traveler wires, you have to match that Leviton with the specified auxiliary model. But you could set up That master with any zwave auxiliary switch, even a battery operated model, that supports zwave direct associations, in a “virtual 3 way” which would not require the physical traveler wire, and some won’t require a neutral at the auxiliary position. I know that’s a little more complicated, but I just wanted to mention it, because it is an option.

Again, once you get a master switch wired to the outlet, you can use many other auxiliary devices via radio control. So just another possibility. :sunglasses:

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So here’s yet another option. I’m not sure how the wiring would go, would need some thinking.

Replace the outlet with a smart one. One example linked below.

Then all you need at the switches is power and neutral to run their radios. Neither switch would need to physically switch anything.

This eliminates any issues with the smart switch being rated for 15amps as they wouldn’t be switching anything. You could use the ZEN26 as I believe their latest firmware provides an option to not operate the internal relay.

Did the diagram I put in the original post show up?

Everything being said is totally correct. In my ideal situation I would have two switches (the smart switch and a satellite) controlling the outlet. If I go with a smart outlet I render the two switches pointless which doesn’t allow someone to manually turn on that outlet at the switch.

If you see the diagram you can see that the outlet has 2 sets of white/black in that box. One comes from the breaker. The other goes to the switch. The two switch boxes are connected via 3 wires (red/white/black). Regardless of what color is used for what, is there a way to wire this to work with the Leviton switches? I can get hot and neutral to the switch through the outlet - but then there is no load wire.

Really the issue here is that the power goes to the outlet first. I would have to run another set of cables between the outlet and the switch to get the hot to the switch and have the load come back down. Without removing a ton of drywall, that’s not possible.

If you set up a virtual three-way between an auxiliary switch and a master switch and both are Z wave, they can work even if the smartthings hub is not working. The same is true between a master switch and an outlet.

But as soon as you add Zigbee into the picture, you lose that. The hub Has to be operational in order for the switch to have control over the outlet.

I don’t think I would do that for the wall switch for an outlet. It just seems too risky from a safety point of view.

I included the Zigbee outlet because I had it handy. Use a Z-wave outlet.

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If you go with a smart outlet and, as JD suggested, Z-wave association, the switches will function just as they do now. Only they’ll be doing it by Z-wave communication rather than physically breaking a connection at the switch.

I think all you would need is to run both the hot and neutral from the outlet to the line and neutral terminals on the first switch, then use your travelers to carry both of those to the second switch.

All that does is give the smart switches power to operate. Switching would happen by Z-wave commands from the switches to the outlet.

Unfortunately you don’t have enough wires to make a smart switch work. As you have said you won’t be able to get load back to the receptacle. A smart receptacle is your only option without running an additional wire, unless there is an outlet closer to one of your switches on that same circuit. If there is an outlet closer and you can run a wire to the switch, you can use it for line power and then use the 14-2 Romex going back to your outlet as load.

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Thanks all! I hadn’t considered the smart outlet/smart switch combo. It’s a bit annoying to spend $100+ in hardware for one lamp, but that’s less annoying that redoing the drywall to run additional wires. I always appreciate the help on these forums. Keep up the good work!


Sounds like a plan!

Get zwave plus devices for both Master switch and outlet and make sure the switch supports association. (The outlet doesn’t have to: it’s the target, not the trigger.) Do not get a dimmer switch. Get a regular on/off.

If you are creating a virtual connection between the switch and the outlet then the switch does not have to match the amps for the outlet.

If The switch will control the outlet directly by cutting the current, make sure it supports at least a 15 amp load (but then you wouldn’t be using zwave association and could just have your same dumb outlet). @Richierich would know more, but I’m just concerned that you’ll have to do some rewiring to break the existing electrical connection between the switch and the outlet. (I know some of the right questions for wiring, but I leave the answers to the experts. :wink:)

The auxiliary switch will depend on which master switch you get.

Take a look at both models of Zooz switch.

One of them will work with a dumb switch for the aux without a change of wiring.

So one Zooz switch and one zwave outlet.

You might need to connect different wires in the outlet box to electrically isolate the outlet from the switches.

Zwave associate to outlet.

Can control wirelessly from either smart switch or dumb switch.

Use zwave tweaker in classic smart things app

Also, double check the specs, the Zooz zen21 is rated for 15 amps.

Question to others: does zwave tweaker work in new app?

If not, how to set zwave associations in new app?

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He doesn’t have neutral at the switch so even the Zooz won’t work. The load of the current switch is basically a break in the line level voltage so he doesn’t have enough wires to get both line and load to the switches.

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Can he power a smart switch (any brand) in the box even if the switch doesn’t physically switch the outlet?

So line and neutral connections to a smart switch but no load connection at all.

I’m not an electrician, but that definitely seems plausible to me. The wires would likely just need to be reconfigured at the outlet.

Same here, to both those things.

But I’m vague on wiring outlets!

If @ritchierich says it’s possible…

Is the diagram correct or am I not understanding it.

He shows 3 wires capped together.

If the line from the panel to tied in to a wire to the outlet, then the wire from the switches don’t matter.