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Discussion Starter · #1 ·
I'm wiring a new lighting fixture to an existing switch which has juice running through it already.

> The first 14/2 Romex cable will run from the existing switch to the lighting fixture, but the hot and ground wires will be the only ones connected (the neutral remains unconnected).
> A second 14/2 Romex cable will run from the lighting fixture to a junction box where I'll only connect the neutral (and ground).


A Home Depot employee mentioned that running both hot and neutral in close proximity (aka Romex) helps keep the cable cooler (and thus is safer). He wasn't an electrician and didn't appear to be extremely knowledgeable in this area, so I'd thought I'd ask if anyone has heard that before.

Question: Is it unsafe to run Romex where only one of the hot or neutral is connected?
 

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I=E/R
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I'm wiring a new lighting fixture to an existing switch which has juice running through it already.

> The first 14/2 Romex cable will run from the existing switch to the lighting fixture, but the hot and ground wires will be the only ones connected (the neutral remains unconnected).
> A second 14/2 Romex cable will run from the lighting fixture to a junction box where I'll only connect the neutral (and ground).


A Home Depot employee mentioned that running both hot and neutral in close proximity (aka Romex) helps keep the cable cooler (and thus is safer).
:laughing::laughing:
He wasn't an electrician and didn't appear to be extremely knowledgeable in this area, so I'd thought I'd ask if anyone has heard that before.:eek:

Question: Is it unsafe to run Romex where only one of the hot or neutral is connected?
Unsafe, don't know but it won't work :no:
Find a good electrical book instead of people in stores...
 

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liscenced electrician
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its fine, but i think you are wiring up your light a little akward. Can you draw a diagram and maybe we can suggest a more standard way?
 

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It's NOT fine. The hot and neutral MUST be in the same cable. The exception to this is a switch loop, and even now under 2011 there must be a neutral run with a switch loop.

300.3(B) Conductors of the Same Circuit. All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (B)(4).

So you know, the "grounded conductor" is the neutral, and nothing in (B)(1) through (B)(4) applies.
 

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liscenced electrician
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404.2 makes it sound like you can't dead end a 3 way anymore because there would be no nuetral. It sounds like you must run the power from one side and switch leg from the other side




nevermind, i guess its just for single pole switches. 3 way and 4way don't apply
 

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404.2 makes it sound like you can't dead end a 3 way anymore because there would be no nuetral. It sounds like you must run the power from one side and switch leg from the other side




nevermind, i guess its just for single pole switches. 3 way and 4way don't apply
You do now (under NEC 2011) need a neutral for any lighting switch.

(C) Switches Controlling Lighting Loads. Where switches control lighting loads supplied by a grounded general purpose branch circuit, the grounded circuit conductor for the controlled lighting circuit shall be provided at the switch location.
Handbook commentary:
Changed From 2008

•tabspacer404.2(C): Added new requirement covering installation of grounded conductor at all switch locations where lighting loads are controlled.
 
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Discussion Starter · #9 · (Edited)
Updated plan

Okay, based on your feedback, here's my revised plan.


From the junction box, run both hot and neutral to the fixture. Run a second hot and neutral from the fixture to the switch.

Inside a metal enclosure within the fixture there are now 9 wires (hot, neutral, ground from each of switch, power source, and lamp) which will be connected as follows:
* power hot to switch hot
* power neutral to light neutral
* switch neutral to light hot
* grounds are all connected to fixture casing
 

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Okay, based on your feedback, here's my revised plan.


From the junction box, run both hot and neutral to the fixture. Run a second hot and neutral from the fixture to the switch.

Inside a metal enclosure within the fixture there are now 9 wires (hot, neutral, ground from each of switch, power source, and lamp) which will be connected as follows:
* power hot to switch hot
* power neutral to light neutral
* switch neutral to light hot
* grounds are all connected to fixture casing
This is correct, but the white wire to the switch is NOT a neutral. It is simply a white conductor that is bringing the feed from the fixture to the switch. This white should be remarked to a hot color like black, red or blue at both ends. A permanent marker works best for this.
 
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I=E/R
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will be connected as follows:
* power hot to switch hot
* power neutral to light neutral
* switch neutral to light hot
* grounds are all connected to fixture casing
In the fixture box you will have a white wire nutted to the black feed.
At the switch both the white and black from the switch loop will be connected to the switch.
Back at the fixture, the black from the switch loop will be connected to the light.
Put black tape at both ends of the white wire in the switch loop.
 

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A "Handy Husband"
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Okay, based on your feedback, here's my revised plan.


From the junction box, run both hot and neutral to the fixture. Run a second hot and neutral from the fixture to the switch.

Inside a metal enclosure within the fixture there are now 9 wires (hot, neutral, ground from each of switch, power source, and lamp) which will be connected as follows:
* power hot to switch hot
* power neutral to light neutral
* switch neutral to light hot
* grounds are all connected to fixture casing
Still does not meet NEC 2011 (if that is a concern). You are not providing a neutral at the switch box. Easily corrected by running 14/3 from the fixture to the switch.
 

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Discussion Starter · #13 · (Edited)
This is correct, but the white wire to the switch is NOT a neutral. It is simply a white conductor that is bringing the feed from the fixture to the switch. This white should be remarked to a hot color like black, red or blue at both ends. A permanent marker works best for this.
Understood, but thanks for reminding me to mark the white as a hot. Is it bad practice to mark using electrical tape?


Still does not meet NEC 2011 (if that is a concern). You are not providing a neutral at the switch box. Easily corrected by running 14/3 from the fixture to the switch.
If I run a neutral down to the switch (via 14/3) where would I connect it? The neutral wouldn't be part of a circuit, would I just nut it.
 

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If you run an unneeded neutral you would just cap it and tuck it in the back of the box.

The grounds also need to connect to any device like a switch or receptacle.
 

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Discussion Starter · #17 · (Edited)
Thanks to everyone for your knowledgeable and quick replies. You've truly been a greater help than I could hope for.

I understand NEC requires hot and neutral to be run together (now) and I will run my cable accordingly. :thumbup:


But one thing keeps bugging me. If the neutral is grounded, then the neutral is already at roughly the same voltage as the grounding cable (neglecting slight noise differences). In other words, you're not going to get shocked by holding the neutral and ground wires. So what is the additional safety benefit in running the neutral alongside a hot wire run that already includes a grounding cable? :huh:

In my case, the switch loop doesn't require the neutral. It provides no utility within the switch and will just get capped there.
 

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Here is something that should keep you awake tonight.
The neutral is technically and correctly labeled the Grounded Conductor.
It is supposed to carry current:yes:
The ground wire, correctly labeled the Grounding Conductor does not carry current except in a fault.
 

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A "Handy Husband"
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Nope. Use 12/4 or 12/2/2.
re: dead-ending a 3 way switch

Will 12/2/2 (2 hots, 2 neutrals) be compliant? You would have to mark one of the neutrals as hot. Seems 12/4 (3 hots, 1 neutral) is a more compliant?

This whole neutral in every box is getting to be a "nanny state" thing.
 
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