THHN


What is THHN Cable?

THHN is a type of electrical wire or cable that is commonly used in building construction.


What Does THHN Mean?

The meaning of THHN is “Thermoplastic High Heat-resistant Nylon-coated” and it is a designation for a specific insulation material, temperature rating, and condition of use. THHN wire is suitable for dry and damp locations.


Where Can I Shop for THHN Cable?

View our selection of THHN wire by clicking here.


How Is THHN Cable Applied?

Often, THHN insulated wire is used in the alternating current electrical distribution systems of all types in North America. This THHN wire is usually at voltage levels from 110-600 volts. THHN wire insulation is also used for aluminum and copper conductors, either solid or stranded depending on size.


What Are Some THHN Cable Specifications?

There are many wires that are rated THHN as well as THWN, and these are usually suitable for use in dry locations up to 90° C or wet locations up to 75° C, depending on which you use. With THHN, the conductor is suitable for use in dry locations up to 90° C. With THWN-2, the conductor is suitable for use in wet or dry locations with temperatures up to 90° C, but 75° C if exposed to oil or coolant.


What Are Specific Examples of THHN Cable?

View some of our THHN products by clicking any of the links below. Nassau Electrical carries a wide selection of THHN wire to meet your specifications.


The THHN Cable

As the name suggests, the Thermoplastic High Heat-resistant Nylon-coated (THHN) cable has high resistance to heat. This feature makes it an ideal cord for use outdoors in locations where high temperatures are common. Unlike other cables, which typically not designed to withstand high temperatures, the THHN cable maintains high performance in environments of high temperatures. Its performance is not altered by the heat. That is why the cable is mostly used in fire alarm control systems, heat control systems and push-button stations. The cable is also moisture, oil and gasoline resistant. This is because of its thermoplastic and nylon sheath insulation. It is, therefore, suitable for use in both dry and wet working environments.

The THHN cable is flexible and durable, making it a perfect cord to use in environments where durability is a valued factor. In dry and wet areas, the cable should not be used at temperatures that exceed 90°C. In areas where the wire is exposed to coolants and oil, its operating temperature must be maintained at 75°C or lower. The THHN cable uses 600 volts in all applications. Often it is used in commercial cable and conduit trays for branch circuits and feeders.

This cable meets the Underwriters Laboratories (UL) standards as well as those set by the Canadian Standards Association. It also meets the American Society for Testing and Materials Miscellaneous (ASTM) requirements and is compliant with the Restriction of Hazardous Substances (RoHS).

The variant THHN cable types include;

  • The THHN Wire 6 AWG 19
  • The THHN Wire 8 AWG 19
  • The THHN Wire 10 AWG 19
  • The THHN Wire 12 AWG 19
  • The THHN Wire 14 AWG 19
  • Aluminum THHN
  • Copper THHN
  • Tray cable TC TC-ER Shielded THHN PVC 10, 12 and 14GA
  • Tray cable TC TC-ER THHN PVC 18GA
  • Tray cable TC TC-ER THHN PVC 16GA
  • Tray cable TC TC-ER THHN PVC 14GA
  • Tray cable TC TC-ER THHN PVC 12GA
  • Tray cable TC TC-ER THHN PVC 10GA
  • Tray cable TC TC-ER THHN PVC with ground 12GA-500MCM

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