There are five main types of electrical wiring that are commonly used, especially in a home, including triplex wire, main feeder wire and panel feed wires. Other types of wire include nonmetallic sheathed wire and single strand wire.
Triplex wire is a type of electrical wiring that feeds the electricity to buildings from outdoor electrical wires. These wires run from the building to the power pole. Main feeder wires are another type of wire used by electrical companies. These insulated wires are black and are often seen jutting from the service weather head. Panel feed wires are the type of wires that attach to the main electrical panel or breaker box in the home. They bring electricity to the breakers, which then distribute the power throughout the home.
Nonmetallic sheathed wire, also called Romex wire, is a wire made of two to three conductors and a ground wire all coated in plastic. This is the typical wiring used in homes and has a rating of either 20, 30 or 45 amps depending on the installation of the wire. In some homes, single strand wire is necessary. These wires have insulation, and several fit into a single pipe. Each type of wire has a particular load and is installed for different conditions.