Why DOES NM-3 cost so much more than NM-2?

Discussion in 'Electrical Forum discussion & Blog' started by Homeownerinburb, Apr 11, 2012.

  1. Homeownerinburb

    Homeownerinburb New Member

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    I have pondered this for years. 12-3 generally costs ~80% more than 12-2. Same ratio in 14ga.

    Why this should be, I don't know. It would seem to me that the one cable consists of about 1/3rd more material than the other. It will weigh about 1/3rd more. Is the cost of shipping the stuff even remotely a fraction of the cost of getting onto the shelves?

    Seems to me that vastly the most expensive component will be the copper, with the oil for the plastics coming in second, and by a fair bit. A 1/3rd increment in the cost of making the stuff should result in about a 1/3rd increment of the price to purchase?

    Yet another good argument for working with flex conduit and individual conductors.
  2. hj

    hj Moderator & Master Plumber Staff Member

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    They make and use a "jillion" feet of NM-2. NM-3 is not used anywhere near that volume so economiees of scale come into play. A Rolls Royce uses the same number of parts as a Chevrolet, but the prices are no where near the same. If they tried to produce a million Rolls a year on an assembly line its price would come down also.
  3. Homeownerinburb

    Homeownerinburb New Member

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    I have considered that and find it not a convincing argument. Sure, 20X as much 2 conductor gets used as 3 conductor, but it is not as if the huge spools of black, white and bare conductors that get bundled into the cable are any different for the two products. The sleeves are chemically the same and are poured into not similar hoppers to be extruded and wrapped around the bundled conductors.

    I don't buy the idea that the distinction is as huge as a Chevy vs a Rolls. Not only are there many less Rolls' built, but they use vastly different quality components and materials.

    I'd say "because they can" but market forces always flatten that out. Nobody has a lock on the production of NM.
  4. ballvalve

    ballvalve General Engineering Contractor

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    Pull two runs of 14-2. The cost of 3 wire cable makes me look toward conduit often, especially with a few hundred rolls of copper from the good old days. Have to keep it under big lock and key.
  5. Chad Schloss

    Chad Schloss Member

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    i wish someone sold 14-2-2 by the foot. i ran a bath fan/light/night light last week. had to pull 14/2 and 14/3 to it. panasonic bath fan j box is real tight. ran 14/2 to the fan/ 14/3 to the two lights. 14-2-2 is sold at big orange in 100 ft folls i think and it was like 150+ when i only needed max 15 ft.
  6. jimbo

    jimbo Plumber

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    I find 12/3 or 14/3 at just about 12 to 15% higher than the corresponding /2

    Economies of scale can't be ignored. Besides the actual manufacturing process, there is the cost of maintaining an inventory item. For a slower moving item, that can translate to a higher piece of the margin.
  7. hj

    hj Moderator & Master Plumber Staff Member

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    I think I would call it 14/4 and its demand is even less than for 14-3. If you needed 14-4 why did you basically install 14-5?
  8. Chad Schloss

    Chad Schloss Member

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    because you need a hot for the fan, and it needs a neutral in the same line(bundle of wires, nm-b) (14/2) the light and night light have 2 separate hots and share a neutral. (14/3) grounds all get tied together. neutrals get tied together in the switch box. ask an electrican, its all legit :)
    Last edited: Apr 11, 2012
  9. kreemoweet

    kreemoweet New Member

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    Since when has seller's cost been a determining factor in market price? Only in the phony examples they teach in beginning economics
    courses, but that has little to do with reality.
  10. Homeownerinburb

    Homeownerinburb New Member

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    A good moment to consider conduit......
  11. Homeownerinburb

    Homeownerinburb New Member

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    You are talking about charging the product a rent for sitting on the shelf. The faster it moves, the less per item it pays. Legitimate but complex.
  12. jimbo

    jimbo Plumber

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    If you don't think there is a cost to have an item sitting on the shelf then apparently you are not familiar with business concepts such as turns, gimroi, ebita. That's ok,,, but please believe that items don't sit on a shelf, or in a truck , for free!
  13. Homeownerinburb

    Homeownerinburb New Member

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    Oh, I did not say it was not valid. I said it was complex. Especially on the back of my damned truck.
  14. hj

    hj Moderator & Master Plumber Staff Member

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    If you did not have $100.00 tied up in that "wire in the back of your truck", you could put it in the bank and get interest on it.
  15. Homeownerinburb

    Homeownerinburb New Member

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    Well, not much interest. Not enough to buy a burger by the end of the year.

    But I certainly take your point. That and about 50 assorted electrical boxes and various receptacles and switches, etc.
  16. ballvalve

    ballvalve General Engineering Contractor

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    That burger you get a the end of the year in interest would be from the pink-slime value menu.

    I have several thousand pounds of copper wire that has quintipled +++ in value. Thats far better than money in any sleazy mutual fund or the .09% "saving" account. Keep it cold and dark, and if the insulation eventually gets tired, scrap it at 3 to 4$ a pound. I used to do copper roofs, and had pallets DELIVERED for $1.75 a pound. Flashed my house in lead. Now thats a real lifetime money saver.
  17. hj

    hj Moderator & Master Plumber Staff Member

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    quote; copper wire that has quintipled +++ in value.

    But like gold, it only buys something when you sell it. "Value" is what people will pay you for it.
  18. ballvalve

    ballvalve General Engineering Contractor

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    Location:
    northfork, california
    Salt, sardines, water, gold, nickels and ammunition for your guns have the most intrinsic value. The 100$ bill is at the top of folly. Unless India and China crash, copper can only go up.

    The copper came from a tungsten mine that won the 2nd world war for us. 11,000 feet in the sky. Waterpowered from drainage. Along with a truckload of wire came 3- 300' 10-3 mining extension cords. Look like garden hoses. What I paid would not have bought just those. They sold the steel mill building, perhaps 100'x800' for 50 bucks. 200# snowload. The mill was so advanced that it operated on imported CHINESE ore for several years. And it was 900 miles from a port. Big loss to the USA.
  19. Homeownerinburb

    Homeownerinburb New Member

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    525
    Location:
    Los Angeles, CA USA
    Wow. Go and start a discussion of economics!
  20. ballvalve

    ballvalve General Engineering Contractor

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    Read the book " the mine in the sky" near Bishop, ca.
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