Electricians: can neutral be anything but white?

[LD1]

Are you just trying to save money by running fewer wires or is there some reason you want to limit yourself to using the smallest sized conduit you can?

Eddie

Fewer wires to make it easier to pull 4 circuits worth through 1/2" EMT. I still plan on pulling a ground and not relying on conduit connections staying tight over the years. So, if I can get 4 circuits down to 7 wires instead of 9 and it will work just the same, is easier, and cheaper, why not.

The reason for 1/2" is because the standard single boxes I have only have knockouts for 1/2". Only the double boxes have a few 3/4" knockouts. I didnt want to have to go through several boxes making the knockouts bigger.

Since this is a shop, are you planning on using power tools? Are they all going to be 20 amp lines with 12 gauge wire?

Yep, mostly power tools. And yes, all 20a 12ga thhn/thwn wire

Is there a cost savings in only buying one color wire?

Eddie

Not really. I have spools and spools of wire already. I can use whatever I want

If you ran 12/3 romex, you wold have two hots for one neutral and a ground. I wouldn't change that ratio anymore then that.

Eddie

Exact same thing I want to do, only not romex. Just stranded wire. 2 hots (on different phases) for each neutral. But I want 2 of those circuits in the conduit, thus wanting a different color for the second neutral so I can keep track of what neutral belongs to what phases.

In my shop, I ran 12/2 for each circuit with my lights on a separate line.

Eddie

That would be the same as if I ran 4 neutrals to go with the 4 hots. But if the extra neutrals are not needed for anything, Why use extra material and make more work for myself.

First, I am a certified (master) electrician in Wisconsin. Here is an NEC pipe fill chart.

Conduit Fill Chart

The ground is not counted as it is not a current carrying conductor. You also have to consider the derating factor.

Electrician Testing- A guide for all Electricians: Wire Ampacity and Conduit Fill Calculation

This table shows that for (your case) you would have to derate 8 conductors in a raceway to 70 %.

If you did share the neutral with 2 hots you would have to have the hots on a 2 pole breaker. You have to be able to open the hots with a single switch handle (breaker).

Personally, I would use 3/4" or 1" conduit for the main runs. It leaves room for future expansion.

I have already seen the tables. De-rating doesnt apply per-say. The When the conductors are good for 30a, 70% derate is still 21a and adequately protected by a 20a breaker. Thus, I am allowed up to 9 CCC in conduit on a 12a breaker.

The two pole breaker is is something I havent seen mentioned yet though. I assume that is just a safety thing some someone doesnt get bit by the neutral that is tied to two breakers, and the unsuspecting person only killed one of the breakers?

 

[buickanddeere]

Just mark your neutral with white tape at both terminations.

As long as the one neutral is shared with line 1 and line 2 , it's actually preferred. There is no phases with single phase . With three phase power , one love each from phase A, B and C can share a neutral.

 

[downsizingnow48]

Not an electrician but as contractor did a fair amount of residential, garage, shop wiring.

Code will allow using metal conduit for the ground, but I would run continuous green insulated ground wire inside the conduit anyway.

As Eddie says, long as you use 12/2 with a ground for each 120v circuit (or equiv single wires in conduit) you will be OK.

 

[LD1]

As Eddie says, long as you use 12/2 with a ground for each 120v circuit (or equiv single wires in conduit) you will be OK.

I know that will be okay. Thats 1 hot and 1 neutral for each circuit. Thats not the question. The question a shared neutral serving 2 circuits.

I know that it is okay provided the two circuits arent on the same phase. The question becomes about using another color wire, and if it works with GFCI's

 

[s219]

GregbkH hit the nail on the head, esp about the two pole breaker requirement and derating the wire (and that is dependent on wire insulation type and ampacity I believe). Plus, 9 wires in 1/2" emt sounds like a pain and increases risk of damage when pulling. Go as big as you can with the conduit. You can always put an intermediate box and run 1/2" from that to the individual receptacles/switches.

The only times I have used white tape to mark a neutral was when the wire only came in one color, usually black. That was some 1/0 aluminum XHHW for my generator install. I taped the neutral with white tape on both ends and in increments along the length. Although there was no requirement to differentiate the two hots, I taped one of them red just in case I needed to know in the future. And while the ground wire was a thinner gauge and easily identified, I taped that green. Never know who is going to need to access or understand the wiring in the future.

I know guys who share neutrals between two different phases, but to me it's never been a consideration. You sort of need to have the tow circuits feeding the same area to make it practical, and I am generally only running individual specific branches when I do work. I suppose for a pre-wire it makes more sense.

 

[buickanddeere]

Not saving any money with 1/2" conduit. Plus the right radius makes it more difficult to fish and pull wires with . Going to 3/4 doubles the internal area over 1/2".
Splurge big with a couple of bucks and use #12awg black, red, white and green. One wiring mistake or time wasted puzzling over wires with missing tape saves nothing.
Two 8ft or 10ft ground rods or a 8ft deep buried ground plate and bare #6 copper to the ground lug in the breaker panel.
The neutral bar should float free of ground on it's own insulated bar.
Anybody that tells you ground and neutral are the same thing. Kick their stupid behinds and tell them to go away.

 

[grsthegreat]

Good luck running 9 thhn #12 in. 1/2" conduit. Youll be cussing yourself blind in no time.

And why would you be pulling all 9 thru a single gang box with only 1/2" holes anyways. Pull main run into a 4 square box with 3/4" knockouts then branch out to the smaller boxes with 1/2" conduits.

On top of derates, theres also box fill to worry about.

Running 2 hots to one neutral is 100% legal as stated above. Remember... The feeds to. Your house are done this way. There is one real issue with doing it this way though, if you lose the neutral at any time (ie the wire nut comes apart or whatever) you WILL have 220 going thru all of those circuits. Its amazing how fast a sawzall or bench grinder will run for about 5 seconds before it smokes. Or how bright a light bulb will get

Grey and white only. The way we do it in the field is to group a set of wires together and tape the group. So for a 10 wire run, i would tape together one set of black, red and white wires on both ends, then id tape a set of black, red, white and green on both ends for next run. The final wires are left untaped. Easy to sort out. Personally i hardly ever use 1/2" trade sized pipes for anything. I find them useless.

I also never use small junction boxes. I always use the 4"x4" variety with the raised commercial covers. They allow more wire space room, look more professional, and allow for single or double outlet combinations. Art not very expensive either

 

[buickanddeere]

Run lights on their own dedicated breaker with nothing else shared. Reduces dimming when tools start. Also prevents staggering around in the dark when somebody overloads a receptacle.

 

[davesl708]

I would not scrimp on the electrical. You are doing the minimum and no room for expansion.
Also, If two hots share a neutral then both hots will have to be shut off to work on one.
Also, the next person to have to work on the electrical may not know the neutrals are shared.

I few extra dollars now will save remorse later.
Good luck with your project.

 

[LD1]

GregbkH hit the nail on the head, esp about the two pole breaker requirement and derating the wire (and that is dependent on wire insulation type and ampacity I believe). Plus, 9 wires in 1/2" emt sounds like a pain and increases risk of damage when pulling. Go as big as you can with the conduit. You can always put an intermediate box and run 1/2" from that to the individual receptacles/switches.

The only times I have used white tape to mark a neutral was when the wire only came in one color, usually black. That was some 1/0 aluminum XHHW for my generator install. I taped the neutral with white tape on both ends and in increments along the length. Although there was no requirement to differentiate the two hots, I taped one of them red just in case I needed to know in the future. And while the ground wire was a thinner gauge and easily identified, I taped that green. Never know who is going to need to access or understand the wiring in the future.

I know guys who share neutrals between two different phases, but to me it's never been a consideration. You sort of need to have the tow circuits feeding the same area to make it practical, and I am generally only running individual specific branches when I do work. I suppose for a pre-wire it makes more sense.

Yes, I think 9 wires is gonna be a pain. Thats why I was trying to get down to 7 wires. Not really sure how to incorporate an intermediate box. Box is mounted on shop wall, and outlets are going to go around the shop. Was wanting just 1 run of conduit instead of multiple. So, starting at the box, The first 3 outlets on breaker 1, next 3 on breaker 2, next three on breaker 3, and last 3 on breaker 4. (Thats 1/2 of the shop, gonna be the same thing coming out of the other side of the panel going around the shop). So, I only need 7 wires (or nine if I dont share neutrals) for the first 3 boxes, then I can drop off a hot wire and only pull 6 for the next three boxes. Then I can drop off a hot and a neutral. Next three only need 4 wires, then the final three get 3 wires pulled.

Hope that makes sense.

Not saving any money with 1/2" conduit. Plus the right radius makes it more difficult to fish and pull wires with . Going to 3/4 doubles the internal area over 1/2".
Splurge big with a couple of bucks and use #12awg black, red, white and green. One wiring mistake or time wasted puzzling over wires with missing tape saves nothing.
Two 8ft or 10ft ground rods or a 8ft deep buried ground plate and bare #6 copper to the ground lug in the breaker panel.
The neutral bar should float free of ground on it's own insulated bar.
Anybody that tells you ground and neutral are the same thing. Kick their stupid behinds and tell them to go away.

Your posts just make no sense to me. Not saving money....3/4 cost more. About 50% more. While EMT isnt expensive, and the savings isnt great, it IS saving money.

Not sure what you mean about splurging big on wire. I already have all the 12ga wire I will ever need. Said that several post as back.

And service from meter to panel is already in. We are talking about inside wiring in this post. Not ground rods.