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	Subject - NEC: Stranded vs. Solid audiochris Can somebody point me to a specific location in the NEC that outlines the use of stranded and solid wire? Specifically the pertaining to the difference in resistance between the two. I have someone arguing with me that stranded wire is less resistive the higher the number of strands. I have informed him that for all intensive purposes they are equal. I have explained ohms law to him and he still doesn't get it. I would just like to be able to back myself you with some specifics. Also, has anybody ever heard of a "skin effect"? This guy keeps bringing this up as well. he says quote: "it will be less resistive in an A/C circuit due to the skin effect, where the current only runs on the outer edge of the wire" I've never heard of this before, I think it must be some marketing gimick that he took as fact. Thanks for your help. Chris JimmyDee Chapter 9, Table 8 Conductor Properties. If you look closely at the stranding up to #8, the resistance is actually a very small, tad bit less on the solid than on the stranded. Which is opposite of what your unlearned friend said. So, you are correct. Usually skin effect is only applicable on high voltages like above 144,000 and then there are other considerations to deal with. Basically your friend, to put it bluntly, don't know what the heck he is talking about. Jim audiochris thank you stedder Isn't skin effect something like 80 percent of the current travels on the outer 20 percent of the conductor? He's probably thinking if you had #8 solid you only have 1 strand but #6 stranded has 7 or 11 or so. The cross section would still be relativly the same in the end?! sparkie2170 When an alternating current flows through a conductor, there is an inductive action whereby the current in the conductor is forced toward its surface. The current density is grater at the surface than at the center, and under certain conditions, practically no current may flow along the axis of the conductor.-American Electricians Handbook After paying $85.00 for it I want to get my moneys worth! lctrc789 Here is another post to help back you up. Jimmy is right skin effect will not matter unless you get way up in the voltage and as far as less resistive, Well, your friend is not an electrician or hasn't studied the basics much has he? Solid and stranded make a very insignificant difference where you are concerned. bigbillnky Not to argue, but consideration must be made for skin effect at all voltages. Frequency is one of the factors that govern skin effect. This is the reason harmonics cause additional heating in electrical systems and equipment.