Neutral wire question

I am installing Inovelli switches around my houses. For 3 ways setup with dumb switch, it require a neutral wire but the 3 way lights in my hallway, its power source is in the light gang box so no neutral wire in the switch gang box.

But ....
This one dual switch gang box does have a neutral wire which belong to the switch that control the room outlets where floor lamps are plugged into. The outlet's switch hot wire is on a separate breaker than the 3 way light hot wire is on

I been googling all night and couldn't find an answer for this probably because smart switch is not as wide spread yet.

I am wondering if I am breaking any code or rules using pig tailing the neutral wire from the outlet switch Romax wiring into the neutral terminal on the Inovelli switch since all house neutral wires ties into the same terminal bar inside the breaker box.

I have another 3 way light switch which doesn't have a neutral wire in the switch box but there is a switch on other side of the wall in a different room with a neutral wire however that switch hot wire is also on a separate breaker and I am thinking of replacing both switch gang box and run a romax wiring from one switch from one side of the wall to the other switch on other side but I will only be using the white neutral wire. The black wire will be unused between both switch box since both already tied into it own breaker.

What I am asking does anyone know if there are any code violation "borrowing" neutral from a different power source than the one that it's on?

Yes, you are. You are not supposed to steal a neutral from another circuit.

You can search for that term...every article you'll find says don't do it. The only reason I know, I had to check this out for one of my 3-ways. :slight_smile:

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AWwwwwwwwwww s

Thank you .. I never thought to search using "steal" as the word ..

That mean I have to run a Romax 2 wires from the light gang box to the switch.. the black one will be unused

I don't think there is a single romax wiring on the market correct?

Any neutral is fine to use Bill. It doesn't have to come from the same circuit

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This is not safe advice and can result in someone getting shocked in the future. Please do not suggest users violate electrical safety code.

While everyone thinks of all Netral wires being equal, since they land on the neutral bus bar in the electrical panel, they are very unique to the circuit they are paired with. AC current flows through the Neutral wire just as much as it flows through the Line/Hot wire. When a circuit breaker is de-energized, a properly wired circuit's corresponding Neutral will have no current flowing on it. If you steal/borrow another circuits Neutral, there can/will still be current flowing on it. This can lead to someone getting shocked/electrocuted when working on what they believe to be a de-energized circuit.

Also, using another circuit's neutral requires that neutral wire to possibly carry too much electrical current, posing a fire risk. Two breakers sharing a single neutral can easily overload that neutral wire causing it to overheat and start a fire.

Please don't do it.


That is not correct if you read the electrical code that I linked to Scott. It is very unsafe and can cause a fire.

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Ummm its ground I believe you guys are referring to. Neutral and ground are completely different

What exactly is your wiring? By definition both switches have to have 3 wires. Line, load and traveler. One of the boxes has to have a neutral that is going to the lamp.

There are different ways to wire a 3-way. Any of the ones on this page look like your setup? It will make it easier to figure out what you need to do.

it is this one ...

No, a ground is a safety element to an electrical circuit. It should NEVER carry any current except when performing its role to save someone's life. It is an emergency path to ground to prevent someone from being injured due to an electrical problem.

Again, please do not suggest these overt electrical code violations. Electrical safety should never be compromised in order to add home automation. Do it safely, or don't do it at all, please!


Ground is used as a direct path to earth for things such as surges.
Neutrals is used mostly as low power sources for things like smart switches.

The difference is that using ground to neutral is the fact there is no resistance to earth and why using ground as a neutral is not only illegal but dangerous. Using a neutral from a different circuit is only dangerous if someone used a ground for a neutral on that circuit. Neutrals are resistive circuits meaning that the line only receives x amount of power and if that resistor that limits power fails and you are using a ground then that's the issue.

No Scott. Neutrals carry the exact same amount of electrical current as the Line/Load wires. They are sized for that same amount of current, and thus you can never share a neutral between two breakers. See my explanation above please.



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Then do not have a neutral at either switch box. Your only option to do this safely would be to run a 3-wire romex from LT2 to SW1. Or use a device that doesn't require a neutral wire. There's no neutral wire for this circuit at either SW1 or SW2? When was your house built?

That is totally incorrect. Your neutral will carry just as much electricity as your hot wire does. That's why it's there. It's not like a ground on a DC circuit. This is AC. You can get electrocuted from a neutral or a hot.

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Not for this circuit, there is no neutral at the switch box but there is a hot wire in SB1 where I wanted to install the Inovelli just no neutral wire.

Look like I will have to run a 2 wire romax from the F2 (based on my image) light gang box to SB1 and only use the white wire. I asked someone if I can run just the white wire and not use Romax wire, he said no .. either conduct it or use romax wire ..

Forgot to add that my house was built in 1979

And I am sticking with Inovelli switches because of its notification led feature.

Switches or dimmers? The dimmers do not require a neutral.