Some of the common points are explained below: Thermoplastic is cheaper than thermoset and nylon coating is required for the insulation system’s rating.

THHN/THWN-2 has a thermoplastic insulation, while XHHW-2 is a thermoset insulation. Thus, you can use them for the wiring system of commercial or residential buildings. THHN wire is approved by building codes.The building code restricts the use of Romex® in residential buildings.You can use it for both indoor and outdoor applications based on your application requirements. Romex® is widely used for indoor applications due to its less durable PVC jacket which makes it a cheaper option as compared to THHN wire.Whereas, THHN wire is a type of single-conductor wire surrounded by a nylon jacket.So, romex® wires are like bundles of THHN wires wrapped in PVC. Then the whole bundle is surrounded by an outer jacket. Each of these conductors is insulated individually. If you check inside Romex® wire, it consists of two or more conductors.So, let’s find out how they differ regarding applications, construction, and more. However, you can find some differences in their construction and applications. If you check out the Romex® and THHN cables, then you will see, that both of them are widely used in electrical wiring systems. It helps to make it a suitable choice in an industrial environment. This cable has the next interesting properties of oil and coolant resistance.The insulation can withstand sunlight exposure without degrading.Temperature Rating: The temperature rating of THHN cables in dry or wet areas is around 90 degrees while in oil and coolants the selected temperature is around 75 degrees.Jacket: It consists of the Bylon jacket, providing an outer covering.Insulation: It uses the thermoplastic insulator-type Polyvinyl Chloride ( PVC Cable), flame retardant.The copper type includes the standard types ASTM-B8, ASTM-B3, and ASTM-B787. Conductors: The conductor materials of THHN/THWN-2 cable are stranded, uncoated copper or aluminum.Let’s find out some of the important features of THHN/THWN-2 cables below: This cable is used primarily for the rewiring of 600 volts or new construction. Its code standard is defined by the National Electrical Code (NEC). THHN/THWN-2 is the type of building wire. Thhn-2 is essentially the same as thhn.Īfter a brief understanding of the thnn wire, let’s take a deeper study of thhn stranded wire specification. The insulation is PVC, and the sheath is nylon. Thhn wire’s copper conductor can be solid or stranded. Thhn wire is famous for its heat resistance, moisture resistance, and durability, which makes it applicable for various indoor and outdoor electrical appliances, especially in wet environments. It’s the insulated wire with single-core conductors insulated or surrounded by PVC insulation and a nylon jacket. THHN wire is commonly used in building wiring systems. THHN wire refers, to “Thermoplastic High Heat-Resistant, Nylon-Coated”, while THWN, refers to “Thermoplastic High Water-Resistant, Nylon-Coated.” When people buy thn wire they always ask about “what does thhn stand for in wire”.

Wire nuts chart