Running circuits/travelers in conduit

[Gunslinger99]

I've been searching, thinking, more searching but can't seem to find an answer to what I am trying to do and can't seem to wrap my head around how to do this.

Here's what I'm trying to do and I'm sure it's super simple but I am stuck. I'm hoping someone can help me....

I am wiring my garage using emt conduit. Already ran some 3/4" PVC under the slab from the panel to a few locations where I am putting a light switch or outlet.

So here is where I am getting confused....in my lights circuits I'm planning on running power to one end of the 3-way/4-way lighting circuit and switch legs at the other end. Will have two 4-way switches in between the two 3-way switches. I'm also planning on running the travelers through the same conduit I am running the wires for the lighting. All sounding fine to me so far except for this...do I just need to run a colored wire for power and a green wire for ground to one end and then a white for neutral and a green for ground on the other end?

If I wasn't running this through conduit I wouldn't be so confused. Romex is easier it seems...It's which wires to run to each location through the conduit where I am probably out thinking this. I don't think I would need a neutral wire at the power side of my light circuit because there isn't a reason for it (no outlets are going to be in my lighting circuits) and no reason to run a neutral wire through the conduit alongside the travelers as again no need for it.

Am I thinking right on which wires to run through the conduit?

 

[frankush]

Pipe and wire is easier. Think of it this way. One end is the 3 way hot feed (Box A). Other end is switched fixture power (Box D). The travelers, neutral and ground run from the first 3 way (Box A ) to the first 4 way (Box B), continue on to the second 4 way (Box C) and finally end up at the last 3 way (Box D). Switch leg, neutral and ground continue on to your first fixture.

Box A. H,N,G in and T,T,N,G out
Box B. T,T,N,G in and out
Box C. Same as box B
Box D. T,T,N,G in and SL,N,G out

The neutral is the return path back to the panel. No neutral, no worky. Current flows through the hot, through the switches, through the lamps and returns back to the panel, via the neutral. Break the circuit anywhere and it doesn't work. The purpose of a switch? To open the hot leg and break the circuit.

 

[mm08822]

Adding a sketch of your existing/proposed conduit runs and intended purpose of outlets would make this much easier to help you determine what conductors are needed.

 

[Morrison]

I would use the kiss method

 

[Gunslinger99]

I would use the kiss method

Exactly why I posted......

 

[Gunslinger99]

Adding a sketch of your existing/proposed conduit runs and intended purpose of outlets would make this much easier to help you determine what conductors are needed.

Great idea. Will do.

 

[Gunslinger99]

Pipe and wire is easier. Think of it this way. One end is the 3 way hot feed (Box A). Other end is switched fixture power (Box D). The travelers, neutral and ground run from the first 3 way (Box A ) to the first 4 way (Box B), continue on to the second 4 way (Box C) and finally end up at the last 3 way (Box D). Switch leg, neutral and ground continue on to your first fixture.

Box A. H,N,G in and T,T,N,G out
Box B. T,T,N,G in and out
Box C. Same as box B
Box D. T,T,N,G in and SL,N,G out

The neutral is the return path back to the panel. No neutral, no worky. Current flows through the hot, through the switches, through the lamps and returns back to the panel, via the neutral. Break the circuit anywhere and it doesn't work. The purpose of a switch? To open the hot leg and break the circuit.

This is how I originally thought of doing it but then thought why do I need a neutral to run alongside the travelers? They aren't hooked to the switch....I could just run a neutral from the panel to box D??

 

[skiingman]

This is how I originally thought of doing it but then thought why do I need a neutral to run alongside the travelers? They aren't hooked to the switch....I could just run a neutral from the panel to box D??

Depending on your version of the NEC you need to have a neutral in all the switch boxes. So I learned recently.

 

[Bad Hammer]

Depending on your version of the NEC you need to have a neutral in all the switch boxes. So I learned recently.

Yep. Neutrals and hots need to be in the same raceway.
You need the neutral in with the other wires, otherwise you'll have overheating of the conductors.

 

[rburke65]

Bad Hammer....could you explain this? The wires will over heat without a neutral being present?.... Really? So without it, you can't cancel the magnetic flex capacitor? I've never heard of this......not that I have heard of everything, but....

 

[tfi racing]

Bad Hammer....could you explain this? The wires will over heat without a neutral being present?.... Really? So without it, you can't cancel the magnetic flex capacitor? I've never heard of this......not that I have heard of everything, but....

Absolutely,I'm sure your welder circuit will surely overheat and kill your entire family unless you run out now and pull in that magical lifesaving white conductor...

 

[dledinger]

Depending on your version of the NEC you need to have a neutral in all the switch boxes. So I learned recently.

Should only be one switch box in 3-way and 4-way circuits under the current NEC.

 

[Gooch]

Depending on your version of the NEC you need to have a neutral in all the switch boxes. So I learned recently.

This is incorrect. under the 2011 NEC, you need to have a neutral in every switch box EXCEPT if the wiring means allows for adding it when needed(i.e. conduit)

under the new 2014 code it will only be required in one box that serves a lighting load.

 

[Gunslinger99]

Getting a little confused here. Will I need to run the neural alongside the travelers then?

 

[dledinger]

The idea behind the neutral is to accomodate automated devices in the future...timers and remote devices cannot operate without a neutral. As Gooch pointed out, since you have conduit and can run a neutral later, you don't even need to worry about it.

 

[Bad Hammer]

Bad Hammer....could you explain this? The wires will over heat without a neutral being present?.... Really? So without it, you can't cancel the magnetic flex capacitor? I've never heard of this......not that I have heard of everything, but....

Yeah, I'll try. (The NEC requires this for a reason guys.)

NEC 300.3(B)] requires all conductors of the same circuit to be contained in the same conduit or cable, unless otherwise permitted in accordance with 300.3 (B) ((1)through(4)). This requirement mostly pertains to metallic raceways, such as the aforementioned EMT conduit.

NEC 300.3(B) (3) does permit conductors in a nonmetallic sheath (romex/PVC conduit) to be ran in different cables, although I personally feel that is never a good practice.

NEC 300.3(B) requires all circuit conductors of an individual circuit to be grouped to reduce inductive heating, but this isn't nomally a problem with non metallic wiring methods.


But since Gunslinger99 is running EMT (metallic) conduit this requirement does apply to his situation.

 

[Bad Hammer]

Getting a little confused here. Will I need to run the neural alongside the travelers then?

If ran in EMT conduit, then yes.

 

[Gooch]

If ran in EMT conduit, then yes.

No you dont

 

[Bad Hammer]

No you dont

Well, you're right, he doesn't have to. And I surely can't make him.
But, to be legal by code, and safe in practice, he should.
And that's the way we have always done it, or we wouldn't pass inspection.
To do other wise is bad practice, and to defend it is bad advice.
By the way, frankush has it exactly right in post #2.

From the 2008 NEC Code Book:

ARTICLE 300 -WIRING METHODS :
Chapter 3 Wiring Methods and Materials

300.3 Conductors.
(A) Single Conductors. Single conductors specified in Table 31O.13f~) shall only be installed where part of a recognized wiring method of Chapter 3.
Exception: Individual conductors shall be permitted where installed as separate overhead conductors in accordance with 225.6.
(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).

I'm not an inspector, and my family won't be sleeping in that house, so I'm simply offering my opinion.
After all, that's all I have invested in this conversation.

 

[skiingman]

This is incorrect. under the 2011 NEC, you need to have a neutral in every switch box EXCEPT if the wiring means allows for adding it when needed(i.e. conduit)

under the new 2014 code it will only be required in one box that serves a lighting load.

Thank you very much for explaining that!

 

[CoopVA]

I concur with Bad Hammer... He's spot on...

 

[frankush]

Well, you're right, he doesn't have to. And I surely can't make him.
But, to be legal by code, and safe in practice, he should.
And that's the way we have always done it, or we wouldn't pass inspection.
To do other wise is bad practice, and to defend it is bad advice.
By the way, frankush has it exactly right in post #2.

From the 2008 NEC Code Book:


I'm not an inspector, and my family won't be sleeping in that house, so I'm simply offering my opinion.
After all, that's all I have invested in this conversation.

The key here is "it's bad practice." Wiring it the way I suggested, leaves no doubt as to where that neutral originated from. If I open a box and see a SL coming from one pipe and a neutral coming from another, I have to ask, where did that neutral come from?" Does it belong with this circuit or was it just convenient, so the electrician used it? Keep it simple.