Types of electrical wiring

Residential wiring is less complex then commercial electrical wiring. In most residential applications cable is used instead of conduit and wire. There are several wire types that are generally used in residential wiring.

The first type of electrical wire is NM wire. This is the most used in residential applications. There are usually two wires and a bare ground wire which is wrapped in a type of paper. All three wires are protected by a plastic wire coating called sheathing. The ground wire will be positioned in between the two conductors. This type of wire is not made for wet or high moisture situations.

The wire that is designed for high moisture applications is NMC. In this type of wire all thee wires are enclosed in plastic. This type of wire is used predominantly in crawlspaces and in basements.

Type UF wire is used in outdoor applications. This type of wire is predominantly used to supply power to exterior lighting. This wire is also enclosed in plastic casings.

In older homes BX armored cable was used. This type of electrical wire is covered with a metal cover and was used because it is difficult to damage and to puncture. This type of wire is very durable and has the advantage of having the metal covering act as a grounding mechanism. BX wire is not used in most residential applications today because of its cost and difficulty of installation. Usually this type of wire is used in modern commercial applications.

Electrical wire is sized by gauge numbers. Correct wire sizing id very important in residential and commercial buildings. Of too small a wire is used it can overheat if it is not capable of carrying the current placed on it. When this occurs it can blow a fuse or trip a breaker or in the worst case it can cause a fire.