THHN Wire

All Electrical Wire

All Electrical Wire

See All

About THHN Wire

THHN wire is the most common type of single conductor electrical wire used in the industry. You could possibly buy THHN, THWN, THW, THHW or THWN-2. Years ago each type was made for each specific installation, but nowadays the standard way to manufacture and purchase it is to buy the multi-rated THHN/THWN-2 version as a universal building wire.

Does THHN Wire come in different colors?

Yes, THHN wire comes in a standard 10 colors including: Black, Brown, Blue, Gray, Green, Orange, Red, Violet, White and Yellow. Occasionally a distributor or manufacturer will have THHN in pink as well but it’s a little more unlikely. You can also stripe THHN or THWN if you need another color option. Usually the green wire is made into a green with a yellow stripe but you can use your imagination.

Does electrical wire come without the nylon coating on the wire?

Yes, you can get something called THW wire. The “N” in THHN and THWN both stand for Nylon so you can see that the THW would be the THHN without the nylon. It will be difficult for you to find THW because there isn’t a lot of manufacturers that stock this wire. You could use hook up wire in place of it but it will be much more flexible than the electrical wire. Hook up wire can come in bare copper instead of its usual tinned copper and the smaller awg sizes can come in a solid version. However, the bigger awg sizes will be much more flexible than the standard electrical wire so you should be careful or it might get bunched into the conduit.

What’s the difference between Romex® and UFB cable?

Romex® and UFB cables are both made with THHN wires on the inside of the cable and provide the exact same function. However, Romex® wire was made to be an indoor cable with a cheap outer jacket to make it more affordable for electrical contractors. The UFB cable is an underground cable used outdoors because of its tough outer jacket. UF stands for underground feeder and the B stands for ground wire. Most UFB cables come with a ground wire anyways because it’s usually needed for the job.

Copper THHN Wire

Copper THHN wire is a common type of single conductor building wire used in homes and buildings to run power to outlets and lights. Copper wire is first connected to the electrical box in the basement, then it travels through the walls to each outlet giving it power for any small appliances or electrical equipment.

THHN 10 awgTHHN 12 awg and THHN 14 awg are known as circuit size electrical wiring. They’re most commonly seen as the wires inside of Romex® cable. Romex® bundles 3 wires together and wraps them in a PVC jacket so that the electrician can run 3 wires at once instead of one at a time. Click on the size you’re looking for to buy it online. We offer small quantity spools of 100′, 500′ and 1000′ in the circuit size THHN wires.

THHN 8 awgTHHN 6 awgTHHN 4 awg and THHN 2 awg are the next few larger sizes when the application needs more power than the circuit size applications. The larger sizes are hooked up to things like a stove, dryer or hot tub. These also come in a Romex® cable which you may know as Romex® 6/3 cable. That means all of the wires inside are 6 awg and there are 3 conductors. Most times there will be an additional bare copper ground wire included inside the PVC jacket.

Any larger types of copper THHN wire are seen as 1/0, 2/0, 250 mcm and so on. These very large electrical cables are used to bring power to the electrical box from the street. For simple terms, the THHN 4/0 cable will bring 1000 AMPS to the electrical box in your basement allowing smaller wires to pull 10 amps to each outlet, 30 amps to the stove, 40 amps to the hot tub and so on. Once your electrical box reaches the maximum an additional wire will need to be brought to the box from the street.

THHN THWN Electrical Wiring For Your Home

Here are some basic details about the THHN wiring in your home. THHN or Thermoplastic High Heat-resistant nylon is a wire coated in plastic and runs through conduits. It is used for general building purposes such as residential and commercial wiring. The National Electric Code recommends and allows it to be used in dry locations only. It can operate in a location with a maximum temperature of 194°F. It can also operate up to a maximum power capacity of 600 Volts.

The THHN Wire consists of a metal-based conductor and its polyvinyl chloride insulation is flame retardant, heat resistant, and moisture resistant. The wire is abrasion resistant with its nylon jacket or approved equivalent by the Underwriters Laboratories.

The standard types of THHN wire include the solid conductor THHN, stranded conductor THHN, and aluminum conductor THHN. The solid conductor THHN wire has a solid copper conductor and its American Wire Gauge (AWG) is sized 14-10. The stranded conductor THHN wire, on the other hand, has an AWG size of 14-4/0 and stranded conductor of 19 copper strands. The aluminum conductor is not made of soft hardened copper but with aluminum. Its specifications are the same with those of the stranded and solid copper THHN wires.

The use of THHN wire within a circuit is identified through a color scheme. This policy is based on the National Electric Code. THHN wires has jacket colors and they are available in red, blue, white, black, orange, green, yellow, purple, brown, pink, tan, and gray. Further, the THHN wire is also manufactured in a dual wire rating that is THHN/THWN-2. The THHN-THWN-2 wire is approved for use in wet locations and it can operate well in locations with a temperature of 167°F.

It is often used in conduits, raceways, branch circuits, services and feeders. However, the usage of THHN wiring in your home must first be approved by licensed electricians. It is available at very affordable prices. The nylon coating, however, has often made it difficult to install this wire. Thinner THHN wires can also be leaked or broken down. The polyvinyl chloride jacket can also produce a toxic smoke when it is burned by fire.

Here are some electrical wiring tips that can help you ensure energy efficiency within the home. First, check your appliance wiring and their proper electrical connection regularly. For example, you have to check the proper wiring of small appliances like radio and electric coffee pots as well as major appliances like electric range, oven, and refrigerator. Install dryer cords, range cords, ovens, and dishwashers properly. Check how these appliances are connected to THHN wires and other electrical wires needed.

Another tip for THHN wiring in your home is to always keep in mind that there are bad and good electrical wiring connections. Note that a flooded home may pose dangers to your electrical wiring connections. Check whether you are making the proper knots with the electrical wires.

More importantly, make sure that you are following safe and secure electrical connections especially with the electric meter, electrical disconnects, electric panels and sub-panels. Further, you have to correctly use every electrical wire such as THHN wires.

THHN THWN THW Acronym Meanings

THHN, THWN and THW are all types of single conductor electrical wire used in homes and buildings to deliver power. Years ago, each acronym was a completely different wire with different approvals. Each type was specific to an application and cost as such. One with a nylon coating, for instance, was more expensive than one without. However, nowadays, there is a universal THHN-2 wire that covers all approvals from all variations of THHN, THWN and THW.

THHN Wire and THWN Wire

Thermoplastic, high heat, Nylon coated. THHN wire without a dual approval of THWN is not water resistant. The added “W” stands for water resistant so that it could be installed outdoors and in conduit when THHN wire could not. However, again, remember that they’re all combined into a universal wire now. If you buy THHN wire on our website it will have all of the attributes of each acronym discussed on this page.

THW Wire

Thermoplastic, Heat and water resistant wire. This acronym is missing the “N” for nylon coated. The nylon coating looks like the little piece of plastic over a shoe lace and protects the wire in a similar fashion. Without the nylon coating, the wire will be slightly cheaper and provide less environmental protection to THW wire. It’s actually difficult to find THW wire without the additional approvals of THHN and THWN because they were all combined into one.

You can probably imagine how difficult it was to design, manufacture, stock, and price each of the separate types of electrical wire. That’s why they were combined into a universal THHN-2 wire at a very attractive price.

Buy THHN-2 Wire here >>