There are totally different causes for all sorts of wire and cable together with naked copper. Typically wire has insulation and typically it would not for particular causes. Engineers work laborious to supply a kind of wire for each software on the market with approvals to go together with it.
Naked copper is also referred to as a floor wire. It’s not insulated in any respect so it has no safety. It’s largely utilized in properties as a floor wire and has one of the best conductivity with out insulation. So so long as it is not going outdoor then electrical contractors do not thoughts utilizing it.
Naked copper can be the bottom for many kinds of wire and cable. It comes stable or in smaller awg sizes wrapped collectively to equal the identical gauge. Utilizing the smaller awg sizes provides the wire extra flexibility to bend round corners. You would possibly assume that you’d at all times want probably the most versatile as a result of it might solely be higher however that is not at all times the case. Typically electrical contractors want it to be extra stiff to allow them to ship it a good distance via conduit.
A inexperienced THHN wire is also referred to as a floor wire when the wire must be outdoor. Inexperienced calls out the very fact the THHN is a floor wire and the explanation for the insulation is so it has safety in opposition to moisture. It could actually then go outdoor and in conduit whereas it nonetheless acts as a floor wire. The explanation for utilizing it indoors with out insulation is just because it is cheaper. Typically you would possibly see this wire with a yellow stripe as effectively.
There is not at all times a floor wire in each cable. If you happen to want one then I like to recommend speaking to your cable gross sales individual and ensuring they know that as effectively. Most corporations that offer wire additionally provide the naked copper so that you should not have an issue getting it when you want it. You may often request a specification sheet to be sure you are getting the precise cable you might be on the lookout for.