Old wiring and Z-wave switched: No Neutral. Any options?

I was under the impression that Lutron’s solution doesn’t work with LED or CFL bulbs.

Nope, works just fine with dumb dimmable LEDs and CFL’s.

You may be thinking of the older GE Zwave switches which didn’t require a neutral. Those only worked with incandescents.

But Lutron is an engineering company and went to work and just a couple of years ago introduced the Caseta line specifically to address the issue of LEDs without neutral wires.

These are the ones that they’ve tested, but most work fine.

http://www.lutron.com/en-US/Service-Support/Pages/Technical/Design-SelectionTools/LEDDimmerMatrix.aspx

http://www.lutron.com/TechnicalDocumentLibrary/3683266_Caseta_CFL%20LED%20Bulb%20list.pdf

Are there any outlets on that line? If so, then (if I understand this right) anything plugged in with a ground will present a potential shock hazard as someone touching it can provide a path to earth. Also, if there is a GFCI earlier in the path, it will probably trip as the switch will look like a voltage leak to the GFCI. At least, I think these are the main worries.

The missing neutral problem has been a big pain for me. Someone ran some of the switches in my house using 3 wire cable, but didn’t bother to connect the neutrals. That’s a easy fix. Just irritating. Sloppy. I have other switch loops run with 2 wire cable. These are hopeless. . . .

I bought some z wave relays that I’m going to install in some of the light fixtures.

That’s what I ran into as well, but mine is a new house. I understand why they didn’t run the neutrals to the switch, it’s just a pain because what we are doing is more advanced than the standard builder wires for today. The best option I found and in my book it’s still not really safe, is to pigtail to an outlet or switch near by. From what I understand the CGFI is typically off the line side so it shouldn’t be a problem. As for the neutral, it shouldn’t be a problem electrically. Note though, I’m saying Neutral meaning the path back to the panel intended to carry current vs the Ground which I am calling the bare wire that is a safety path back to the panel, which is not intended to carry current except in a problem situation.

And that’s interesting. In the circuit box the neutrals and grounds are all tied together. And I have often wondered just what might happen should a ground be used as a neutral… Not that I’m advocating this.

So the reasons this should not be done are well explained here:

https://www.quora.com/Is-it-ok-to-use-earth-or-ground-as-a-neutral-in-AC

Which is old news and correct. But a Z-Wave device is going to require an extremely small amount of current and I wonder just how unsafe it would be.

Totally unsafe to power from the ground instead of the neutral. Definitely not a good idea. :rotating_light: :fire_engine::ambulance:

As far as branching a neutral from a nearby device, that can indeed be done both safely and to code just depending on the exact wiring set up. @Navat604 or one of the other electricians in the community can explain more about that option. :sunglasses:

I thought that exact same thing. There is only about 20 volts going to the “add-on” switch. So I tried it. My lights lit up and everything. Then I tried to turn them off. They wouldn’t turn off. I’m still not sure electrically why that happened. I can’t come up with a reason why that would cause the lights to shine, but connecting through the ground didn’t. But it did. The only thing I can think is that maybe there is some current slipping onto the ground somewhere that was able to find it’s way back through the circuit and power the lights that way. Either way, I finally fished the ground wires from the closet switch directly behind the switch I was working on over to this one, and when I connected to that. everything worked fine. Go Figure.

There is nothing strange about this. The ground and neutral are very similar because they are using the same reference point but for different purpose. Neutral is for carrying load current back to your panel and ground is for protection and should not have any current. You are taking a high electrical shock risk for using ground instead of neutral. Ground wire is usually one size smaller than line or neutral. That’s why it’s easier to pull. If you are pulling a ground wire. Why not a neutral as well. It’s not that much more difficult to do and will give you better sleep without thinking about fire or shock.

1 Like

I don’t have ground or nuetral so I have been using bulbs everywhere. I would love to be able to use switches.

I wanted to reply to this relatively quiet thread to share my own experiences and how a buddy of mine who is an electrician helped me out to get this set up. In my situation, I had a neutral at one switch, but not at the second switch (considered the add on switch going forward). The products that I used were the GE Z Wave Toggle Switch and the the GE Add On Switch. I ran into the same problem that spawned this thread, and luckily my friend was able to help me out.

If you look at the original installation for the three way switch, you have the power coming from A and out to the light through C. (see my own reply to see diagram)

Take note that in the Add On switch instructions, this is nearly the exact same thing, except that the connection to the light happens at the second switch box (at the add on switch).

(see my own reply to see diagram)

What he did was to connect the main switch directly to the load (to the light) like the original instructions, then pigtail T1 to the neutral. At the add on switch side, he capped off the load to the light (instead of connecting it to T1), and then connected the jumper for neutral to T1. The rest of the connections remained the same with T2 going as the Traveler.

(sorry about shoddy diagram, I used Paint to stitch together the two manuals and then edit to show what he did)

1 Like

Only allowed me to do one image at a time…here is original instructions for the Z Wave Switch

Here is the original diagram for the add on switch.

@Navat604 or one of the other electrical experts in the community can say more, but almost certainly what your friend did, if he is a licensed electrician, is to bring over the neutral. Not the ground. A ground should never be used to substitute for a neutral. But it is quite common to “fish up” a neutral from another nearby outlet or switchbox and tie it in to the auxiliary switch.

Not sure why your electrician buddy violated code by using the ground for your neutral to the add-on switch when you have enough wires from your primary box to add on box for neutral, traveler and ground which the add-on requires.

1 Like

You’re absolutely right, it was neutral, not ground.i said it right in one spot and wrong in the other. I think the wiring diagram shows it right.

1 Like

Ah it was my mistake. It was not to ground but to neutral.

2 Likes

Hey, that’s why electricians get paid what they do: this stuff is confusing! :wink:

Just wanted to get it clarified for people who read this thread in the future.

Fishing a neutral through from another switch box is what worked for me in almost every instance in my house. There was only one place where I couldn’t find a close by neutral and I ended up using an aeotec in-wall (in the fixture actually) dimmer in that case. If I were to do it again I’d just put a cree smart bulb there instead.

In 3-way switch setups you only have bring the neutral to one of the switch boxes. That’s where your “main” switch goes, and since the add on switch (the jasco ge ones I used anyway) only require 2 wires instead of the 3 used in a standard “dumb” configuration, I was able to send signal to it over one of the existing traveller wires, neutral over another, and abandon the 3rd.

That said, now that this is all done I don’t think I’ve touched an actual switch in weeks.

Can u just fish a 14 gauge wire from another location through the attic and back down to dummie switch? Does it need to have any conduit or shielding? Is it acceptable to just have the wire

If you’re going to fish neutral from another location like an outlet, you will want it to be on the same circuit to be safe (and compliant with electric code). There’s a really good explanation for why they should be on the same circuit here. From a purely functional perspective, a neutral from any circuit could work (especially given the very low currents we’re talking), but just because it might be functional, it doesn’t mean it’s safe. As for your second question, I would imagine that neutral requires shielding as it is carrying a little current and you don’t want it to short on any metal it might come in contact with. For what it’s worth, I’m not an electrician however I do have a degree in electrical engineering.