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neutral in switch box

billconner

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Been too long since I wired 3-ways. I roughed in for two 3-way circuits. Box A has 2-wire feed, 3-wire to two separate lighting loads, and two 3-wire romex to Box B. Both boxes to have two 3-way switches.

I was going to use the 3-wire runs, one for each switch, but to get neutral to box B, can I split the hot and neutral, one in each cable; or split the travelers between 3-ways between two separate cables?
 
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PCustoms

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Been too long since I wired 3-ways. I roughed in for two 3-way circuits. Box A has 2-wire feed, 3-wire to two separate lighting loads, and two 3-wire romex to Box B. Both boxes to have two 3-way switches.

I was going to use the 3-wire runs, one for each switch, but to get neutral to box B, can I split the hot and neutral, one in each cable; or split the travelers between 3-ways between two separate cables?
I don't think you can split a circuit like this.

When you say 3 wire, are you counting the ground?
 

PCustoms

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No. White, black, red, and bare times two. Enough conductors: hot, neutral, and four travelers. Just the way they are divided.
Pretty sure you should have ran either 14/4 or 12/4 between those boxes....
 

BreeStephany

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To clarify, you have 2 conductor + ground coming into a 2 gang box feeding the lighting circuit, then have two sets of 3 conductor + ground between the first 2 gang box to 2x separate 1 gang boxes and then have the lighting load coming out of the s 2x separate 1 gang boxes via 2 conductor + ground cable?

If so, tie all your neutrals (white wire) from the incoming 2 conductor cable feeding power to the box, tie in your neutral pigtails from your 3-way switches if they are electronic / require a neutral. Tie all of your grounds together, then pigtail the incoming power conductor (black wire) to supply power to the common screw of the 3-way switches. Use the black and red conductors on your 3 conductor cables for your travelers to each secondary 3-way switch.

At the 2x separate 1 gang boxes, again tie your neutrals together, tie your grounds together, connect your travelers and connect the 2 conductor black wire (LOAD) to the common screw on the 3-way switch for power out.

Code requires that neutrals be present at every switch location so that electronic devices can be integrated in the future without using the equipment grounding conductor to carry current from the electronic devices back, which is why the "traditional" method of switch legs to remote switches with both line and load terminating in the same switch location is no longer allowed per NEC.

It is permissible to use the grounding conductor as the "grounded conductor / neutral" solely for electronic switches in retrofit situations where electronic switches are integrated into old systems, but it is a practice that is strongly frowned upon, given the prevalence of electronic / smart devices used, which can put more load on the ground, thus creating a potential hazard if someone were to touch two grounded surfaces that did not have equal potential.

The best way to wire the switches is in the method as I described above.

Just my two cents.
 
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billconner

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To clarify, you have 2 conductor + ground coming into a 2 gang box feeding the lighting circuit, then have two sets of 3 conductor + ground between the first 2 gang box to 2x separate 1 gang boxes and then have the lighting load coming out of the s 2x separate 1 gang boxes via 2 conductor + ground cable.
No. 2 conductor + ground coming into a 2 gang box feeding the lighting circuit. Then from this box the lighting loads, via a 3 conductor + ground. That's all fine, I'm sure. All 14 guage in a 15 AMP breaker (replacing breaker with a combo afci+GFCI for other reasons, primarily at inspectors agreement.)

THEN two sets of 3 conductor + ground between the first 2 gang box to the second 2 gang box. 6 conductors, 2 grounds, and no need in my plans for a neutral but code f
required. (I'll wager inspector doesn't check or ask. He didn't 2 years ago when I did same thing - but not new work, just new switches on existing wiring.) I'd never use a ground for neutral as you describe.

Clearly, it will work just fine - two 3-way switched lighting circuits. The question is can I comply with code for the neutral being a spare conductor in a 3 + ground piece of romex?

I'm sure I could find devices to do what I want and comply, but prefer to use the plain old dumb 3-way switches I have.
 

dave*99

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Been too long since I wired 3-ways. I roughed in for two 3-way circuits. Box A has 2-wire feed, 3-wire to two separate lighting loads, and two 3-wire romex to Box B. Both boxes to have two 3-way switches.

I was going to use the 3-wire runs, one for each switch, but to get neutral to box B, can I split the hot and neutral, one in each cable; or split the travelers between 3-ways between two separate cables?

to clarify----

Box A has 4 cables entering it?
Line, two lighting loads (via a 3 wire cable) and two 3 wire cables to box B?

Box B has only two 3 wire cables in it?

You want to send line from A to B in one of those 3 wire cables.
You want to send neutral from A to B in the other 3 wire cable.

That will work, but you are asking if if is permitted by code?

How is your box fill in box A assuming I understand the layout properly......
 
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billconner

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Yes, yes, and yes.

It's a deep 4 11/16 square by (I think) 2 1/8 with a 3/4" d.g. mud ring. Plenty big. I like lots of room. :) May change to dimmers but don't like the Lutron 3-way dimmer switches I've tried.
 
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billconner

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At East and West ends of same large room. North switch will control sconces on north side. South Switch will control room lights. Pretty simple and intuitive I think. Only switched lights in vicinity.
 

Tundra1

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2020 nec 200.6 (E) exception 1 permits re-marking grounded conductor at termination point to white or grey for multi conductor cable. Not sure if that answers the whole question on overall compliance. But seems that was the root of the question.
 

sparky 1971

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I'm not following the question. So I am going by the thread title. If you are concerned about having a neutral at both switch boxes, don't be. If you can see the entire room from all of the switch locations, you only need the neutral in one box.


404.2(C)
 

PCustoms

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I'm not following the question. So I am going by the thread title. If you are concerned about having a neutral at both switch boxes, don't be. If you can see the entire room from all of the switch locations, you only need the neutral in one box.


404.2(C)
My interpretation was the OP is asking if all required conductors for his 3 way switch circuit can be split between 2 different runs of NM-B.
 

sparky 1971

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My interpretation was the OP is asking if all required conductors for his 3 way switch circuit can be split between 2 different runs of NM-B.
Copied from post #6. But I will admit to the question not being clear to me.

Clearly, it will work just fine - two 3-way switched lighting circuits. The question is can I comply with code for the neutral being a spare conductor in a 3 + ground piece of romex?

A lot of people think that as of 2011 or 2014 a neutral is required in all switch boxes. I used to think that until I looked it up for myself.
 
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billconner

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A lot of people think that as of 2011 or 2014 a neutral is required in all switch boxes. I used to think that until I looked it up for myself.
I'm one of those "lot of people", mostly based on reading GJ. 404.2(c) could be clearer. Please explain when a neutral is required though it seems at least exception 5 applies and no neutral is required.
 

sparky 1971

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What needs explained? If you can stand at each switch and see the entire room, you only need to have a neutral at one box. They want a neutral at the switch box in case a motion detector gets installed. All single pole switches are to have a neutral unless one can be added later. With three ways, if the entire room can be seen from every switch, one motion sensor could cover the room so the sensor could be installed at the one box with a neutral.
 
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