Light Switch Help

Ok so I am not that great with electricity but I need help with a light switch.
I just bought myself a z-wave light switch and it appears that it’s a GFCI.

The first two pictures are on the brand new z-wave light switch.
View image: 20150724 135937

The last two are of the current switch.
View image: 20150724 135710

My question is do I need to put anything on the load screw? I know what the hot and nuteral are but I have no clue what goes in the load screw. The upstairs on my house is VERY old and most of the wires are not really as new or up to date so I am afraid that I may be missing some wires.

What brand and model is the new switch? Different models need to be wired in different ways.

The wiring FAQ may help:

(BTW, for technical reasons, there are no GFCI zwave devices, the two requirements are incompatible, so that’s not the issue you’re seeing. Beyond that, although GFCI light switches do exist that aren’t combos with a receptacle, they’re pretty rare, typically only used for bathroom fans. In the US, there’s no national code requirement for GFCI wall switches like there is for receptacles (although the manufacturers of damp-rated devices may require them, which is where the bathroom fans come in). Switches require AFCI instead, but that’s the same for both networked and non networked devices.)

Given that you’re unsure what the load screw is for, I’d suggest bringing in an electrician. Or if you live near a Home Depot, many offer classes in how to install a light switch which are pretty good and should at least keep you from burning down the house or shorting out your brand new switch. :wink:

it’s pretty simple to wire actually. The black is hot and the white is “common”. the red wire must be the one running to the light. When you wire in your new switch, it will use the exact same three wires. Hook red to “load”, black to “hot” and white to “neutral”. The “traveller” that is covered up is for attaching a remote switch in 3-way situations.
edit: you “should” also ground the switch. there’s either a green or bare wire inside the switch box in most cases. Older houses sometimes use metal conduit and you ground to the box.

In the US, wire colors are not guaranteed, people can and do use whatever bits they have available. Also, the U.S. allows tagging, adding a bit of colored tape to a wire to indicate it’s not being used in the typical way–but the tag may not be at the end you’re looking at.

As a friend who is a licensed electrician often says, wire color just tells you which one to test first.

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I notice the picture of your existing switch is a switch reciptical combo. Is your intent to replace this with a switch only? What does the red wire go to? I assume a light or outlet elsewhere. If so that is your “load” as the black wire is providing power to the switch. So you would hook up black and white as normal to the zwave switch and red to the load.

Good point–since GFCI zwave devices are not made, if the existing device is GFCI it may be against code in the US to replace it with a zwave combo device, which won’t be GFCI.

If it’s being replaced with a single light switch, that’s likely to US code unless, as mentioned, the switch controls a damp-rated device like a shower fan. In which case we’re back to the problem of zwave devices not being GFCI.

Thank you so much for the help guys, I was able to get the light switch working and got it to work with z-wave!

I just have one more question. I bought two of the light switches, and I am trying to install another one by my stairs to the basement.

I connected the black wire to hot and the yellow wire to nuteral but when I turn the power back on and flip the switch, my led light is just flickering. I have no clue why because I know for a fact that that lightbulb works perfectly fine.

Did I mess something up with the wiring perhaps? There were only two wires so I don’t have anything for the load screw.
Pics: / gallery - 20150724 215149, 20150724 215228

The light switch is a ZW500D

Looks like you will need to use the neutral with this switch, meaning you need Hot, Ground, and Neutral for this to work. Just looking at the instructions.

As Edward says, like most zwave switches, this particular device requires 4 wires: hot, neutral, load, and ground.

Again, the wiring FAQ should help.

Seams to be a known issue, even if it’s wired up correctly. Try switching to an incandescent bulb. Researching the quality of your switches is also very important, a lesson I learned the hard way.

Research is always good. Also, regardless of the model, it is essential to read and understand the manufacturer’s instructions for each device. That’s actually part of the national code in the US: follow the manufacturer’s instructions.

On the other hand, since the OP says they haven’t connected anything to the load, the current flickering is problematic, since this switch shouldn’t be sending anything to the bulb. Perhaps the bulb is on a three way circuit and there’s a second switch, probably down in the basement, and disrupting the 3 way by removing one is involved. Or perhaps, as the OP said, they’ve just messed up the wiring. But who knows? Wiring can get weird.

In any case–it’s clearly time to bring in an electrician. Flickering lights with no load connected says this problem is not something to be resolved with Internet discussion. :wink:

He wired his switch in series with the lamp. That switch will not work in that location. If there are a black and white write in the box, the old switch almost certainly interrupted the black wire. However it’s entirely possible the electricity runs from the fixture to the switch in which case that zwabe switch will not work there.


From the images above. The electrician or whoever was doing the wiring used a 3 way switch for a 2 way. You are right that wire in neutral is actually something else. I get nervous when I see switches get hookup like this. This is a huge fire hazard waiting for the next newbie.

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Install that switch somewhere else and install a smart bulb such as ge link. They are cheaper than switches if you only need one

those pictures are of the switch he installed, not a 3-way switch. “traveler” is smart switches only. It’s a single signal wire from another slave switch. I looked over the pics of the 2nd switch you installed, and it’s pretty evident that power is running from the light to the switch. Look over this diagram:
This is very common wiring but it is counter-intuitive for laymen. Wiring up 3-way switches in new installs, it’s almost guaranteed to be wired with power at the light because it’s simply easier to wire them in that manner. You run a 3-way bundle between two switches, hooking the same exact wires to both switches and where they pass the light, you cut the black wire, hook one side to power, the other half to the light, and the white wire from the light goes to the white wire of the load. I just wired up a hall that originally had two switches wired this way, and added a third “four-way” switch. now THAT was complicated. I wish I had started smartthings before doing that. I would have just put in a motion sensor.

In the US, the term “traveler wire” applies to nonnetworked switches as well, and just applies to 3 ways (which in the UK are called 2 ways) where the auxiliary switch is wired directly to the master. It doesn’t imply a “smart” (networked) switch.

Indeed, these days many networked auxiliaries don’t use a traveler wire, instead communicating wirelessly.

There are at least 8 different methods for wiring two nonnetworked switches to control one light. Here, just as an example is a non-networked 3 way switch showing the traveler connection:

I want to install a single smart light switch (GE 15-Amp White Decorator Light Switch | Model #: 45637 that runs 3 BR30 LED can lights. There is a GFCI plug outlet on that breaker, that plug runs all of my computer, 3 hubs, router, modem, small tv and stuff. Also in line with an outdoor GFCI plug. The GFCI has never tripped.
I could install a new plug and breaker for all of that computer stuff since the electrical panel is close & available.

Should I just try it? Any ideas would be appreciated.

Thanks, Murray

Nothing wrong with that as long as you don’t overload the circuit and trip the breaker or having too many things connected to a GFCI could trip it due to leakage.