THHN Wire
THHN (Thermoplastic High Heat-resistant Nylon-coated wire) is recognized for its endurance and fire-resistant properties. The wire comprises a well-conducting metal core (usually copper or aluminum) that is insulated using polyvinyl chloride (PVC). This PVC insulation is then further jacketed with heavy, tough nylon. The wire is so-named after its three primary components (insulation and two coatings). It is a durable workhorse of wires, designed for a range of wiring environments and types of buildings.
Emphasizing specific features of the THHN wire, like the nylon coating, can add another layer of protection against the high abrasion, chemicals, and moisture the wire faces as it serves its purpose. This coating assures the wire will continue to work wherever it is installed, especially in places with particularly harsh conditions. THHN wire can used in branch wiring, branch circuits, as electrical wire, hook up wire and building wire. Multiple THHN wires can be bundled together and sheathed in PVC to create THHN cables.
Products
FAQs
Are THWN wire and TFFN wire used for the same applications?
While both types of wire can sometimes be found in similar applications such as control circuits or machine tools, THWN is generally better suited for environments that might expose the wire to water or higher temperatures. TFFN, on the other hand, is more often used in lighter, indoor applications requiring flexibility.
Industrial Wire Types
THHN Wire
Thermoplastic, High Heat resistant, Nylon jacket insulation (THHN) wire is used in conduit or in cable trays due to its rigidity and tough insulation characteristics. THHN can be stranded (several small strands of wire grouped together), allowing for more flexibility and less chance of breakage, or solid (one wire), which is more durable and rigid. THHN wire is suitable for use in dry locations with temperatures that do not exceed 90 degrees Celsius.
XHHW Wire
Cross-linked polyethylene, High Heat-resistant, Water-resistant (XHHW) wire is very similar to THHN. The difference is that XHHW wire is overall a more durable wire that can withstand higher temperatures and is water resistant. XHHW wire can also be found in both stranded and solid wire options.
MTW Wire
Machine Tool Wire (MTW) wire is much more flexible than THHN wire with insulation that is not as durable, making it a poor choice to run through conduit. The flexibility makes it ideal for winding through tight areas, such as wire ducting in an industrial control cabinet. MTW wire is almost exclusively found in stranded wire, which allows for much of the flexibility and reduces the chances of the wire breaking. MTW wire is intended for use in dry locations that do not exceed 90 degrees Celsius or wet locations that do not to exceed 60 degrees Celsius.