MTW vs THHN | Product Knockout

Our Product Knock-out series is a match-up between two similar products. In boxing terms, think same weight class, same caliber, and same level of experience and amount of exposure. The purpose of these posts are for you to see a side-by-side view of two similar products, and to be able to understand which one will be crowned champ for your specific purposes. Take your seats and prepare for battle, because the gloves are coming out.

MTW wire and THHN wire are electrical PVC wires used in building applications. MTW and THHN are built in accordance with the National Electrical Code for general purpose wiring for installation in conduit or other recognized raceway. These cables share several overlapping characteristics, although there are a few distinct differences that set them apart.

What is MTW wire?

MTW wire stands for Machine Tool Wire, and as the name implies, its primary uses are related to the wiring of machine tools, appliances, and control cabinets. MTW wire is PVC hookup wire, and features either a stranded bare or tinned copper conductor and is known for being durable and flexible. This wire is resistant to heat, moisture, oil, and gasoline, and is rated for up to 600V and for use from -25°C to 90°C. MTW wire passes the VW-1 Flame Test and meets several UL ratings.

What is THHN wire?

THHN wire stands for Thermoplastic High Heat-resistant Nylon, and as we can tell from the name, this wire is made of thermoplastic material (PVC insulation), can withstand high temperatures, and features a nylon jacket. THHN wire is primarily used to carry electrical currents to external power sources. This wire is rated for up to 600V and up to 90°C in dry locations, and 75°C in wet locations. THHN wire features either a bare copper or aluminum conductor, and comes in both stranded or solid, depending on the size.

MTW vs THHN

MTW vs THHN Specs for Construction
	MTW Wire	THHN Wire
Conductor Size	22 AWG-1000 MCM	14 AWG-1000 MCM
Conductor Type	Stranded	Solid or Stranded
Conductor Material	Bare or Tinned Copper	Bare Copper or Aluminum
Insulation Material	Polyvinylchloride (PVC)	Polyvinylchloride (PVC) with Nylon Jacket
Max. Temperature	90°C	90°C
Max. Voltage	600V	600V

Although both MTW wire and THHN wire are well suited for use in similar applications, there are a few characteristics that set them apart and can make a big difference when trying to decide which type of cable will best meet your needs. MTW and THHN can both feature a bare copper conductor, however THHN is available with an aluminum conductor, depending on size. THHN wire is less flexible than MTW wire for two reasons. At the core MTW offers a higher strand count in the conductor, making it more flexible than THHN, which also features a nylon coating that further restricts movement.

MTW vs THHN

Winner by unanimous vote? Instead, it seems as if the match has ended in a technical decision. In this case it looks like our crowned champ depends on your specific application use.

If you’re unsure if THHN or MTW would work best for your wire and cable needs, let Allied help you out! Compare full THHN and MTW specs or give your sales rep a call at 800-472-5655 with any questions.