UL Copper THWN / THWN-2 Building Wire

THWN and THWN-2 wires are rated for 600 V. THWN wires have a maximum operating temperature of 75 °C in wet environments and 90 °C in dry environments, while THWN-2 wires have a maximum operating temperature of 90 °C in both wet and dry environments, offering higher heat resistance.

THWN and THWN-2 wires are manufactured with solid or stranded copper conductors in accordance with ASTM B3, ASTM B8, or ASTM B787 standards. The conductors are insulated with thermoplastic PVC (polyvinyl chloride) and protected by a nylon outer jacket, forming a robust double-layer insulation system. This structure provides mechanical strength, abrasion resistance, and moisture protection. Both THWN and THWN-2 wires are suitable for conduit installation.

THHN/THWN/THWN-2 wire is UL certified, with certification number E544861. UL certification is one of the most authoritative safety certifications in North America, and the cable fully complies with mainstream electrical standards such as the NEC (National Electrical Code). 

While THWN wire is commonly used for installations in standard damp environments, THWN-2 wire is often the preferred choice in modern electrical projects requiring higher temperature ratings and greater current carrying capacity. When installed according to NEC (NFPA 70) requirements, both THWN and THWN-2 wires provide a safe, durable, and code-compliant solution for power distribution systems.

Exporting to 80+ countries and regions, we bring proven global export experience and trusted wires & cables to customers worldwide.

Geritel Wire is a professional Building wire manufacturer. Our THHN/THWN/THWN-2 wire is manufactured in strict accordance with relevant UL, ASTM, and NEC standards. The conductor uses copper material conforming to ASTM B3 or B787, and the insulation and sheath materials undergo heat resistance, abrasion resistance, and flame retardancy testing. As a reliable wire and cable manufacturer, every batch of our products undergoes rigorous quality and compliance audits before entering the market.

Depending on the cable size and length, THWN/THWN-2 wire can be packaged in coils, small wooden reels, large wooden reels, or cardboard boxes. Coil packaging is suitable for direct wire laying on-site and offers flexible operation; small wooden reels are convenient for rolling out wire in distribution rooms or within buildings; large wooden reels are commonly used in large-scale engineering projects, providing continuous wire supply and reducing the need for splices; and cardboard box packaging is suitable for indoor storage, allowing construction personnel to quickly access the wire.

Geritel Wire Manufacturer holds 50+ international certifications, including UL, cUL, SAA, TUV, CE, VDE, ISO, and others. Our cables meet the highest global quality and safety standards.

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