Very Basic Wiring Question

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mstrlucky74

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If separate neutrals are required and not breaker ties how would YOU run the MC cable(not pipe) in the field to these 1P-20A receptacles?

1.Wall with 3 separate circuits you would not andcould not run the cable horizontal through studs you would run vertical fromeach receptacle to ceiling, correct? Even if it were 2 circuits you couldn’t.If you have 12/3 your hots are good but you only have 1 neutral. Guess if you used FMC then you could pull another neutral.
2.Wall with 3 receptacles on same circuit youcould run horizontally to each receptacle.
 

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You could pull 12/2/2 to receptacle #2, then 12/2 to circuit #1 and from #2 to #3, or 3 HR of 12/2. That's going to be a labor vs materials thing. Three on the same circuit, yes, ceiling to one then daisy chain thru studs, tho you could also jbox in the ceiling from HR and run 12/2 to each from there if walls were already up. Lots of ways to do it.

Why no MWBC, job spec?
 
JFletcher said:
You could pull 12/2/2 to receptacle #2, then 12/2 to circuit #1 and from #2 to #3, or 3 HR of 12/2. That's going to be a labor vs materials thing. Three on the same circuit, yes, ceiling to one then daisy chain thru studs, tho you could also jbox in the ceiling from HR and run 12/2 to each from there if walls were already up. Lots of ways to do it.

Why no MWBC, job spec?
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Thanks. yes, all our specs now always seem to call for separate neutrals.
 
mstrlucky74 said:
Thanks. yes, all our specs now always seem to call for separate neutrals.
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You can ask your supply house to start carrying MC with separate neutrals. I assume that as this requirement becomes more prevalent as I am seeing happen, the cost and availability of this currently "odd" MC will come down. Then you just have to weigh the labor vs. material, but also be very careful about box fill. I would be prone to bringing each circuit up and then using the multi neutral MC for the home run.
 
Strathead said:
You can ask your supply house to start carrying MC with separate neutrals. I assume that as this requirement becomes more prevalent as I am seeing happen, the cost and availability of this currently "odd" MC will come down. Then you just have to weigh the labor vs. material, but also be very careful about box fill. I would be prone to bringing each circuit up and then using the multi neutral MC for the home run.
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That's how I've been figuring. Just like to get install guys perspective on things. Thanks.
 
Apparently they make 12/6 MC with 3 hots, 3 neutrals and a ground (12/3/3?):

http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet257

http://www.prioritywire.com/specs/M...utral Per Leg - Copper Cond - Aluminum MC.pdf

if the HR would be long, complicated, or super tight, it might be worth it to pull some of this 12/3/3 to a ceiling j-box then 12/2 to the receptacles, especially if they are single gang boxes and wire fill would be tight.

eta: Im sure a spool of multi neutral cable is more than 2 or 3x than 2/3 equal lengths of 12/2. OAL weight would be less tho, you'd only need 1/2 or a 1/3 the total # of straps, less KOs in the panel, only need to setup one spool vs 2 or 3, less space in the van, and so on. The labor savings might offset the material cost.
 
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For the 3 circuit wall, three little piggies all the way home.

Ummm... that's the 12/2 kind of little piggies. :p
 
JFletcher said:
Apparently they make 12/6 MC with 3 hots, 3 neutrals and a ground (12/3/3?):
Click to expand...

Lately we have used a lot of 3 and 4 circuit cable. The 3 circuit is typically 10/3-10/3-10/2 with an IG. The 4 circuit is 10-4-10/4-10/1. No idea of cost but I imagine 10/9 (4 circuit is not much more than 10/8 (3 circuit). One pull and you have 3 or 4 circuits at a J-Box, typically with that set up we would use at least a 10x10 can, and bring 2 cables to it. 2 guys can probably pull 60 circuits of home runs in a day, but there is more labor in making up the J-boxes.
 
jmo103 said:
Lately we have used a lot of 3 and 4 circuit cable. The 3 circuit is typically 10/3-10/3-10/2 with an IG. The 4 circuit is 10-4-10/4-10/1. No idea of cost but I imagine 10/9 (4 circuit is not much more than 10/8 (3 circuit). One pull and you have 3 or 4 circuits at a J-Box, typically with that set up we would use at least a 10x10 can, and bring 2 cables to it. 2 guys can probably pull 60 circuits of home runs in a day, but there is more labor in making up the J-boxes.
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What about the reduced labor for securing one wire vs 4, boring one hole for the HR vs 4, etc.?

Arent the neutrals striped with the ungrounded circuit color, ie. black hot wire with a black striped white neutral? If so, it would save time in marking cables as well.

I found 3 hot/3 neutral 12ga MC for $1.40/foot.

http://www.midsouthglobal.net/AFCHomerun.htm
 
ActionDave said:
Who has trouble making up three separate circuits in one j box? Maybe someone on their first day.
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It's not a matter of having trouble doing it. With three 12/2, there is no j-box, which means no materials, no labor for it. Depending on distance and difficulty, pulling and securing balances the no-j-box savings... but you have a more reliable run no matter what. And you will need 12/2 on the job no matter which way you run it. This way, 12/2 is all you need on the job. 12/2 leftovers can be used up, if not on this job, on another. 12/2/2/2 cannot be used up so easily because you typically do not have short runs to do with it.
 
Smart $ said:
It's not a matter of having trouble doing it. With three 12/2, there is no j-box, which means no materials, no labor for it. Depending on distance and difficulty, pulling and securing balances the no-j-box savings... but you have a more reliable run no matter what. And you will need 12/2 on the job no matter which way you run it. This way, 12/2 is all you need on the job. 12/2 leftovers can be used up, if not on this job, on another. 12/2/2/2 cannot be used up so easily because you typically do not have short runs to do with it.
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A laser measure would be a good idea if using the 12/3/3 (or as you call it 12/2/2/2) that way if you need 175', you get a cut length from the warehouse and dont have to (probably waste) 75' of a 250' spool nor order a 500' and sit on the rest for a while...

hmm, starting to see the beauty of just using a lot of 12/2.
 
Smart $ said:
You'll get to fully coerced eventually. :p
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:D

Nah, I like new stuff too much. 12/2/2/2 would have one EGC vs three and one jacket, so it's lighter (I like light) than 3 equal runs of 12/2. Laser tapes are new tech. Less work, same pay. I'll make up one jbox to save having to put up an extra 30 or 40 straps.

Heck, I'd run it once just to say I had done it. You cant learn if you dont try. :)
 
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