So the diagram isn’t 100% accurate, you can’t wire a relay that way. I was only wandering if the smart features of the switch would still operate wired in series with a relay and not directly connected to a load. It would only control the fixture via IFTTT or a scene
The neutral sides are all bundled together at the fixture. He’s not stealing the neutral from the fixture; he’s just tapping into it. All neutrals on the same circuit are electrically equivalent and unswitched. The drawing he shows is correct except that the microswitch also requires a tie-in to the neutral bundle at the fixture.
Think of this another way. This is how it would be electrically. And all of this except the two wires running down to the smart switch on the wall are in the fixture.
Again, you aren’t reading all the way through before replying. Your diagram has power coming to the fixture first. That is a neutral switching circuit instead of a load switching circuit. Most wiring is load switching, not neutral switching. And if that assumption is wrong, the whole plan won’t work. And I didn’t say he’d be stealing the neutral, I said he’d be stealing the load line from switch to light.
The incoming power from the breaker box is coming into the fixture according to his drawing. That gives you line and neutral at the fixture. The microrelay is itself a load, and is powered by line and neutral at the fixture. The relay switches line to the light load. All good so far?
The two wires running down to the wall smart switch are unswitched line and neutral. These power the smartness of the switch. There is no connect to the load terminal in the wall.
Perhaps you didn’t catch the part the power is coming to the fixture first. That’s what his drawing shows, and if line and neutral came to the switch box first, he wouldn’t be trying to figure out a workaround.
And what I am saying is I don’t believe that. Because that’s not how switches are wired typically. At least not in the US.
Why dont you believe that’s how the OP’s house is wired?
I’m just one data point, so I can’t say how common it is. But I’m in the US and all my light circuits have power coming to the fixtures and no neutral wires at the switch boxes.
It makes installing smart switches really annoying. I decided to use Lutron caseta switches since they don’t require a neutral.
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I think it is more common in newer homes, especially now as smart switches are more common, that power enters via the switch box. And that certainly makes smart home installers much happier.
But a switched leg coming from the fixture (where power enters into the fixture) is not the least bit uncommon. In fact, I’d venture to say virtually everyone who is asking in this forum what to do if you don’t have a neutral, and why there is a market for smart switches that work around not having one, is that they’ve encountered this wiring. In my own home, I was fortunate to have neutral in most, but did have two scenarios that where power entered via the overhead fixture.
The colors used in the wiring diagram is a bit confusing. Only black and white…
PS in Holland the box in the ceiling with the light mounting point is the central point in that room. Wiring to switches and outlets in the room are from that central box.
Keeping in mind my frame of reference is U.S., yes, the actual wires would be black and white too. A good electrician would mark the white wire in the switch box with black tape to indicate it isn’t a neutral.
Code in my area now requires neutral and ground wires in all switch boxes. Unsure when this happened but newer houses shouldn’t have issues with smart switches. It’s older ones that may have been built prior to code change.
Do some research before posting your assumptions. Every description of electrical code I can find says to always switch the hot, not the neutral. So, I don’t think it is wired how he thinks.
Where are you getting that neutral is being switched? Look carefully at the diagram in the link I posted. Observe also that the link is to a site that explains electrical wiring. The switch is on the line side coming from the power source. It simply uses a white wire because that’s what’s in the romex - that doesn’t make it a neutral. When the power source is to the fixture first, then you end up with no neutral at all in the switch box at the wall. That’s the wiring variation that gives rise to people asking here a thousand times how to put in a smart switch when there is no neutral. And Lutron makes a switch that is designed for this wiring variation.
As we’ve covered, very recent code changes which may or may not be in effect in all jurisdictions are beginning to require neutral/ground at the switch box. But for existing houses, the wiring alternate shown in the link below is not at all uncommon.
It may also help conceptualize this to point out that the two variations of wiring a light to be controlled by a switch in one location are not different electrically. The switching is still done on the line side and if you draw out the wiring without regard to physical location or wire coloring, they look the same. The other thing a tad odd about the variation we are speaking of is that you use a white colored wire to run line to the switch. That’s why a good electrician will put some black tape on it to emphasize that it is line.
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Where am I getting the neutral is being switched? Do you know anything about electricity? If the load wire comes into the fixture, then it goes to the switch, by definition that is a neutral switched circuit. That’s just a fact and I’m not going to debate it with you. It’s just the way it is. Try googling “neutral switched vs hot switched”. You might learn something.
A neutral switched circuit is when you put the switch on the neutral side. There is no switch on the neutral side. In this wiring variation, the line side runs through the fixture box but isn’t connected to anything. I’ve labelled the drawing to make it clear … follow the path of electricity with your finger.
If the power goes to the fixture first and then to the switch, by definition it is a neutral side switch. That’s simple electronics.
I can assure you that the electricity doesn’t care what the physical path is, or what color the wire is. If you will just follow the path of electricity in this picture, you will see they are electrically equivalent. The switch is on the line side as it should be.
I’m not going to pursue this further since no amount of diagrams or references seems to be helping. But someday I hope you will pick up a basic wiring book, or google search for wiring a light and you’ll find plenty of this (source: https://www.how-to-wire-it.com/wiring-a-2-way-switch.html):
I guarantee, the electricity doesn’t care about anything…but I sure do. And in neither of those cases does the power first come to the fixture, it first comes to the switch. If you follow the path of the electricity, the first place it hits is the switch. The line going down to the switch might be White but it’s a hot. And the line coming back is the load.
I dont think anyone has actually claimed that power goes to the fixture, as in the electrical load, first.
“Power to the fixture first” really just refers to power source going into the fixture box first as opposed to switch box.
That’s how my apartment is wired, and it appears as though that’s how OP’s home is too, at least for the circuit in question.
I’m not sure there’s anything to actually argue about here.
marktheknife is exactly right. The “fixture” is the physical holder for the light bulb, and in this context we are referring to the box it is mounted on. No one but Ryan780 ever said that power was going to the load/light first. Ryan780 said in post 23 regarding my diagram in post 22 that
My diagram showed (by dotted line) that the wiring went through the fixture, but the line side doesn’t go to the light without being switched (the relay is a switch), and the diagram does not show a neutral switching circuit.
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