Smart switch wiring

Hello all, I have Insignia smart switches I am looking to install in my home. It wants me to use the neutral wire so the switch has constant power to maintain connectivity to a Wi-Fi source. I don’t have a neutral in the box. All that is there is the 2 load wires coming from the source using the switch as the break in the connection to control thje light.

The directions say to run a neutral from the source to the switch but if it’s requiring a neutral for constant power for connectivity purposes couldn’t I pair the neutral on smart switch with the load wire that is live coming in and achieve the same thing?

Not an electrician but that sounds like a bad idea. Maybe I’m misunderstanding you, but how would your switch have constant power that way?

Tagging @Navat604

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No. Neutral is not the same as hot (line or load) and that is a very bad idea.

You either need a switch that works without a neutral, else you need the box rewired to bring neutral into the switchbox. Look up smart switch no neutral for various suggestions on switches that work this way. I believe you will find a lot of people like the Lutron Caseta line for exactly this reason.

Do insignia switches work with SmartThings?

Not being an electrician but understanding some basics of it I don’t understand how they are different. If the neutral is meant to give the switch constant power for connectivity purposes how is the load wire paired with the neutral different? The neutral has to have power from somewhere which is why I think/thought pairing the 2 at the switch would be fine seeing as the neutral wire is only off the switch. Coming into the box there is the 2 load wires and a ground.

Please educate me.

I don’t believe they do work with smart things but I’m more or less looking for help from people who would have an idea of what I’m talking about

Let’s assume your circuit looks something like this.


By the way, assuming anything about your wiring is asking for trouble, just in general. Confirming what’s what with a multimeter is essential unless you want to invite electrical shock or a fire.

But back to the diagram. How can wiring the neutral terminal on a smart switch result in the completion of a circuit with live on one side and neutral on the other? You would be adding “neutral” either to the line wire coming from your breaker, or your load wire going to the switch. It just doesn’t add up.

I have circuits like the one in the diagram, and I added an aeotec micro switch in the ceiling. That’s where the neutral is.

All due respect, you don’t understand the basics of home electrical wiring based on this statement. Not trying to give you a hard time, I had to read up quite a bit on wiring before adding some smart switches, since I have no education or training as an electrician. I’m trying to save you from a broken switch or serious injury.

I’ll try to break it down for you: In a normal consumer application, the power is supplied to all of your devices on one wire, the hot wire. This is usually a black wire run from the service panel to either the switch or the load (light/appliance/etc). In any method, the power out from the service panel must have a return path to the service panel. The neutral (usually a white wire) is taking the power back to the service panel to complete the circuit. The neutral is not supplying any power under normal circumstances, it is merely completing the circuit. In theory, and with ideal wiring scenarios, you should be able to touch neutrals and not receive a shock because they have no power running through them if your load is off. I DO NOT RECOMMEND TESTING THIS AS THERE ARE MANY VARIABLES THAT CAN MAKE IT UNSAFE TO AN UNTRAINED PERSON.

If you are familiar with the function of the ground wire, the neutral is essentially performing the same function. However, unlike a ground wire, the neutral is insulated and designed to be carrying the current under normal operations.

A little more into the theory: If you were to connect the load to the switch and back to the load, the circuitry in the switch could cause a shift of the AC sine wave and then be trying to sync that back to the supplied power. This would be guaranteed to trip a breaker instantly. Furthermore, if you put the switch in line in a circuit not in a home-run line (a line straight from the service panel to the switch box) then whenever the switch is off it would not receive power.

Somewhere in your circuit, a neutral exists. Now whether it exists at the load or at the switch is up to you to determine. If it exists at the switch, we probably wouldn’t be having this conversation. If the neutral is at the load only, you can try to add a neutral wire to the run. If you have conduit (usually about quarter sized metal piping) carrying your wires, and it is a short enough run, you may be able to fish one more wire through. If you have armored cables or Romex wiring, you will probably have to run an additional/replacement wire through your walls.


That’s actually a fair question due to the fact that why are some of the dimmer switches don’t need neutral and still work.
There are 2 factors here that will either make it work or not. The resistance of the load and the switch. Let say the load resistance is 1 Ohm and the switch resistance is also 1 Ohm and the voltage is 120VAC. That means the voltage drop across each resistor is 60VAC. That’s why some dimmers will work without a real neutral by using this voltage drop method. That’s just an example so don’t take my word for it.
A switch is not the same due to the voltage requires to actuate a relay inside and. Possible your switch will work with very low voltage with a dimmer light bulb but that’s risky and hazardous to try.
So the reason why you don’t have neutral at the box is because of the load in between the neutral and the switch. Get rid of the load and you will have true neutral at the box.

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I also have quite a few circuits with power (line) coming in at the light in the overhead. So as this post say your best option is a micro behind the light.

Unless your light is not accessible say vaulted ceilings. Then your in a tight spot.

Get your screwdriver out, your meter out, BE CAREFUL, and verify what wiring you have. Then you’ll have more right answers than you know what to do with.

Andrew, I’m in a similar boat. Except my switches are Leviton switches. If you join the neutral to the hot, it will spark and trip the breaker. The best option is to run a neutral wire to a nearby box in the same circuit and join that neutral. I tried joining a neutral from a nearby outlet that is in a different circuit, it didn’t work. I heard I have 2 choices: Make a homerun to the panel and join the neutral bus or find a way to join the neutral of the circuit the Leviton is on. That may involve cutting the drywall, drilling through fireblocks, etc…
I’m leaning toward the homerun as it’s easier and cleaner for me.

But, I’ll wait to see what others think before doing all that work.

Found this
Instead of diverting energy from the light bulb into a resistor, modern resistors rapidly shut the light circuit off and on to reduce the total amount of energy flowing through the circuit. The light bulb circuit is switched off many times every second.

The switching cycle is built around the fluctuation of household alternating current (AC). AC current has varying voltage polarity – in an undulating sine wave, it fluctuates from a positive voltage to a negative voltage. To put it another way, the moving charge that makes up AC current is constantly changing direction. In the United States, it goes through one cycle (moving one way, then the other) 60 times a second