THWN Electrical Wire

THWN Wire is a type of electrical wire most commonly used in conduit and cable trays for services, feeders and branch circuits in commercial applications. It can be used outdoors because it's water, gas and solvent resistant thanks to its PVC/Nylon insulation.


    THWN Dual Rating

  • All of our THWN electrical wire is dual rated with THHN wire because they're manufactured very similar with almost no cost difference. It's the most standard type of electrical wire on the market because it's used as a single condutor electrical wire and also used in most electrical cables as well.

THHN THWN Wire Information

THWN stands for "Thermoplastic Heat and Water Resistant Nylon Coated" and we have the THWN rating on all of our THHN electrical wire. If our wire was simply THHN rated then it would not be water resistant, however all of our single conductor THHN electrical wire is Tri-rated for THHN, THWN and MTW. It's a stranded or solid bare copper wire with a PVC insulation over it.

South Wire is the manufacturer of our electrical wire and they no longer make the single rated wire for THHN or THWN. It's much easier to just manufacture the Tri-rated material and sell it at the same price.

Copper is a volatile commodity traded on the stock market so the price of wire will go up and down on a day to day basis. Since the electrical wire we have in stock is all copper with a small amount of insulation the price is affected drastically.

We even sell a lot of tinned copper wire with or without insulation. MTW wire comes in bare copper or tinned copper because each type of wire has it's advantages. The bare copper is used in the electrical field as a power supply and the tinned copper has a similar job to supply power but the tin is used to make soldering easier. The tin will melt slightly and adhere to the solder much better.

Since there are very slight differences between THHN wire, THWN wire and MTW wire they are easily manufactured into one wire with all ratings. If you have any electrical wire questions please feel free to call or email to ask them.

When used as Type THHN, or T90 Nylon conductor is suitable for use in dry locations at temperatures not to exceed 90°C. When used as Type THWN-2 or TWN75, conductor is suitable for use in wet or dry locations at temperatures not to exceed 90°C or not to exceed 75°C when exposed to oil. When used as Type MTW, conductor is suitable for use in wet locations or when exposed to oil at temperatures not to exceed 60°C or dry locations at temperatures not to exceed 90°C (with ampacity limited to that for 75°C conductor temperature per NFPA 79).

Conductor temperatures not to exceed 105°C in dry locations when rated AWM and used as appliance wiring material or when used as T90 Nylon. Voltage for all applications is 600 volts. This cable may be installed without the need for pulling lubricant.

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