trouble installing In-Wall Smart Switch

Other Devices & Integrations Lighting & Load Control
1

I tried to install my first smart switch today. (Note: this is not the first time I’ve replaced a wall switch, but it is the first time in this house, and the first time with a Z-wave switch.)

It didn’t work, and I’m looking for advice on what I may have done wrong, and how to troubleshoot it.

The switch I was trying to replace was one of three in the same receptacle. When I opened it up, I found that all three were simple interrupt switches, with only two wires connected (one red and one black each). There were also a big bundle of five (?) white wires connected together with a twist-on connector, and another bundle of bare ground wires crimped together.

So I untwisted and teased out the white wire that seemed to come from the same conduit as the wires attached to the switch I care about. Then I connected it all up as follows:

[ol][li]Black wire to the Line terminal on my smart switch.[/li]
[li]Red wire to the Load terminal.[/li]
[li]White wire to the Neutral terminal.[/li][/ol]

The ground wires, because they were crimped together and then painted, I left unconnected and hoped for the best. But when I turned the power back on, and pressed the switch ? nothing happened. The room lights refused to come on, no matter which side of the smart switch I pressed.

So. Is it that the ground wire really is necessary? And what’s up with the original wiring not having a ground on each switch ? is that even safe?

Or is there likely something else going on?

One more question, if you’re still with me. To see if the switch was OK, I looked for a simpler case: a single switch, the only one in its receptacle, and (like this one) not part of a 3-way setup. I found such in the laundry room, but when I opened it up, I found one black wire connected to the top terminal, and three (!) black wires connected to the bottom terminal (one in the plug-in port, and two on the screw). The receptacle also contained a bundle of white wires crimped together, and a ground wire not attached to anything.

At this point, I closed it all back up and backed away. What the heck might be going on there?

2

[quote=“JoeStrout, post:1, topic:187965”]So I untwisted and teased out the white wire that seemed to come from the same conduit as the wires attached to the switch I care about.[/quote] This is, at least, part of your problem. The white bundle is the neutral wires, but they all need to remain connected to each other. You need to add a small length of wire from your switch and add it to the bundle.

Then I connected it all up as follows:

[ol][li]Black wire to the Line terminal on my smart switch.[/li]
[li]Red wire to the Load terminal.[/li][/ol]

This sounds right. It’s logical, at the least. But you should never assume the function of a wire based on its color. There are many different ways to wire a circuit and sometimes a wires function can change. You should always positively identify each wire, Line, Load, and Neutral before proceeding with a Z-Wave switch install.

The ground wires, because they were crimped together and then painted, I left unconnected and hoped for the best.
Hope can't prevent electrocution, but a ground wire can. Connect the ground. As with the neutral above, add a small wire from your switch to the ground bundle. Don't remove wires from the bundle, they all need to be connected.
So. Is it that the ground wire really is necessary? And what's up with the original wiring not having a ground on each switch ? is that even safe?
The ground is not necessary for the Z-Wave switch to function. It is necessary for safety and the prevention of electrocution. It is not uncommon to find standard switches ungrounded, especially in older homes. However, the National Electric Code(NEC) now requires that all switch faceplates be grounded.
To see if the switch was OK, I looked for a simpler case: a single switch, the only one in its receptacle, and (like this one) not part of a 3-way setup. I found such in the laundry room, but when I opened it up, I found one black wire connected to the top terminal, and three (!) black wires connected to the bottom terminal (one in the plug-in port, and two on the screw). The receptacle also contained a bundle of white wires crimped together, and a ground wire not attached to anything.

At this point, I closed it all back up and backed away. What the heck might be going on there?

You may have found a single gang box, but you did not find a single switch circuit. This is a 3-way switch circuit, where a second switch also controls the light in the laundry room. Either of the two switches can turn the light ON and Off and which wires are energized at any moment will vary with switch positions.

These are basic concepts of household electrical wiring. Household electricity 120VAC or 220VAC can be lethal or start a fire, so I am generally opposed to people who do not understand electricity randomly swapping wires around. For those people, I strongly recommend having an electrician or experienced friend install their Z-Wave switches.

3

All that Z-Waver said and in addition. If you are in the US and you get a fire, if the insurance inspector can prove you messed up on the wiring and that caused the fire, you’ll have a hard time collecting money from them.

I’m not an licensed electrician but I know to greatly respect electricity and what it can do. Granted, I cut my teeth on 220V but even so, 120V still has a nasty kick.

  • Always, always connect the ground!
  • Do not use a neutral wire from a circuit that is on another breaker.
  • As tempting as it is, refrain from using a ground wire as a neutral if you are lacking a neutral.
  • Always assume a wire is live, even if you are sure you switched off the correct breaker. Especially in older homes.
  • In a wet area (kitchen, bathroom etc) use a GFI outlet. It’s code most everywhere these days but older homes do not always have these. Unless that circuit is on a GFCI breaker. But again, most older homes don’t have those.

When working with electricity, these are 2 very handy and inexpensive tools to have. Example links, not endorsing any brand or seller.
non-contact voltage tester - http://www.harborfreight.com/non-contact-voltage-tester-97218.html
electrical receptacle tester - http://www.harborfreight.com/electric-receptacle-tester-32906.html

4

Ah! That’s interesting. The instructions said “Connect the white wire to the neutral terminal (use included jumper wire if needed)” ? but didn’t explain under what conditions that would be needed.

This sounds right. It's logical, at the least. But you should never assume the function of a wire based on its color. There are many different ways to wire a circuit and sometimes a wires function can change. You should always positively identify each wire, Line, Load, and Neutral before proceeding with a Z-Wave switch install.

Sounds good to me! How do I do that? Most instructions I’ve seen say to just copy the wiring of the previous switch, but in this case, of course, the previous switch had neither ground nor neutral connected. And they may well have had Line and Load reversed (I don’t think it would matter with the previous switch). So, how do I go about positively identifying these?

Hope can't prevent electrocution, but a ground wire can. Connect the ground. As with the neutral above, add a small wire from your switch to the ground bundle. Don't remove wires from the bundle, they all need to be connected.

OK. To do that will be fairly involved, but I think I can see how to go about it.

It is not uncommon to find standard switches ungrounded, especially in older homes. However, the National Electric Code(NEC) now requires that all switch faceplates be grounded.

That’s what I thought. In my previous home (which was newer than this one), I never found a bundle of ground wires just hanging out in the receptacle. It doesn’t seem like they’re really doing their job that way.

So, while I’m uncrimping and paint-stripping those ground wires, I may as well install them on the other switches too, right?

You may have found a single gang box, but you did not find a single switch circuit. This is a 3-way switch circuit, where a second switch also controls the light in the laundry room. Either of the two switches can turn the light ON and Off and which wires are energized at any moment will vary with switch positions.

Really? I thought a 3-way switch required a separate Traveler wire. Moreover, while I see that there are many ways to wire a 3-way switch, they all seem to involve a three terminals on each switch – this one has only two. Finally, there is not, in fact, any other switch that controls this light – though the house is full of blank plates over receptacles that are no longer used, so it’s entirely possible that there was a second switch at some point.

These are basic concepts of household electrical wiring. Household electricity 120VAC or 220VAC can be lethal or start a fire, so I am generally opposed to people who do not understand electricity randomly swapping wires around. For those people, I strongly recommend having an electrician or experienced friend install their Z-Wave switches.

I appreciate your concern, and your explanations too.

5

The white should stay in the bundle of neutrals, then you use a white jumper wire to go from the zwave switch to the bundle.

6

The extra black wires in laundry room switch are most likely branch where an electrician ran a power bypass from that box to some other part of the house. Just wire nut all the bottom black wires together including the line wire of your switch. One of them is the line wire to power both switched lights and some other part of the house. The single wire is the load wire.

Atleast in all likelihood that is what you are seeing, not a 3 way switch. Likely when you remove the switch you will notice power somewhere else in the house also goes out. Just keep the three wires together and you will be fine.

7

Just following up for the sake of closure.

Keeping all the neutrals in a bundle, and adding a short jumper wire (thoughtfully included with the switch kit) to the switch, has made it all work. (Or at least, it’s working now as a light switch ? still having trouble pairing it with my VeraLight, but that’s a different issue).

As for the laundry room, yeah, I think it’s clear the previous owner (who did a lot of DIY stuff) just used the switch as a connection point, and bundling them instead is the right thing to do. I haven’t tackled that one yet, but I’m feeling more confident about it now.

Thanks to everyone for your helpful advice.

8

Just make sure to VERIFY what the wires are BEFORE you disconnect them from the switch…

While shallowearth is most probably correct and the three wires connected to the bottom of the switch are branches of the LINE side of the circuit, the only way to be sure is to test the wiring first… This style of wiring at the switch could also be a single LINE wired to 3 separate loads (one switch controlling three lights/outlets)… Remove the switch from the wall box (after turning off the breaker) but don’t disconnect the wires… With the switch in the off position, turn of the breaker and test both the single wire and the 3 wire bundle (use a non-contact voltage tester)… If the 3 wire bundle has power, the bundle is a branch of the LINE side of the circuit… If the single wire has power, it is the LINE side of the circuit and the 3 wires in the bundle are LOAD side.

With Z-Wave switches, you want to make 100% sure you are NOT connecting the LINE wire to the LOAD terminal on the switch… This could destroy the switch (especially the Jasco models)…