Electrical wiring wire types in North America
Wire types for North American wiring practices are defined by standards issued by Underwriters Laboratories, the Canadian Standards Association, the American Society for Testing and Materials, the National Electrical Manufacturers Association and the Insulated Cable Engineers Association.
1.Wires with XHHW insulation are commonly used in the alternating current (AC) electrical distribution systems of commercial, institutional, and industrial buildings and installations, usually at voltage levels (potential difference or electromotive force) ranging from 110-600 volts. This type of insulation is used for both copper and aluminum conductors [15] which are either solid or stranded, depending on size.
According to Underwriters Laboratories (UL) Standard 44,[16] XHHW insulation is suitable for use in dry locations up to 90°C (194°F), or wet locations up to 75°C (167°F).
2. XHHW stands for "XLPE (cross-linked polyethylene) High Heat-resistant Water-resistant." XHHW is a designation for a specific insulation material, temperature rating, and condition of use (suitable for wet locations) for electrical wire and cable.
3. THWN stands for "Thermoplastic Heat and Water-resistant Nylon-coated." THWN is a designation for a specific insulation material, temperature rating, and condition of use (wet locations) for electrical wire and cable.
4. Wires with THWN insulation are commonly used in the alternating current (AC) electrical distribution systems of buildings of all types and sizes throughout North America, usually at voltage levels (potential difference or electromotive force) ranging from 110-600 volts. This type of insulation is used for both copper and aluminum conductors [15] which are either solid or stranded, depending on size.
THHN stands for "Thermoplastic High Heat-resistant Nylon-coated." THHN is a designation for a specific insulation material, temperature rating, a
