Comparing Wires to Wires: MTW Wire VS THHN Wire

by | Jan 6, 2022

Comparing Wires to Wires


Today’s comparing segment will shed the spotlight on the wires to wires, specifically two wires categorized under the Building & Fixture PVC Hook Up Wire category such as MTW and THHN. And although wires like these appear to be identical and have very similar purposes such as designated for installation in conduits or raceways, many specifications and configurations such as the interior metal conductor, strand type, jacketing material and many other factors have a significant impact on the success of the device, or the way apparatus will function. 

MTW Wire, what is it? 

Machine tool wire, also known as, MTW or TEW, is a 600-Volt, 105°C resistant PVC hook-up wire with a stranded copper conductor mostly utilized for internal wiring of machine tools, appliances and controls cabinets. Compared to THHN it is evident that MTW is much more malleable and easier to orient due to the large amount of conductor strands it houses. Along with its malleability, MTW wires are commonly found with not only bare but tinned copper conductors to avoid malfunctioning in settings where corrosion or water is present. In terms of its jacketing and outside layer, MTW wires are heat, moisture, oil and petrol gas proof. Along the same lines, MTW fulfills the VW-1 fire test and meets with UL AWM styles 1015, 1028, 1283 and 1284. 

Image to display mtw wire
image to display Z-Tronix THHN Bulk Wire

THHN Wire, what is it? 

The best way to describe Thermoplastic High Heat-Resistant Nylon, also known as THHN or THWN, is a 600-Volt, 90°C resistant, Thermoplastic insulated, Polyvinyl Chloride and nylon jacketed wire. This wire is capable of enduring 75°C damp environments and typically come in aluminum or copper, stranded or solid conductors.  

How are they similar, or different? 

Despite the fact that MTW and THHN wire are recognized in the national electrical code (NEC) as being appropriate for alike purposes, they have several differences. When it comes to deciding which sort of wire would best suit the project or application, the distinctions will be quite significant. 

One of the first similarities between THHN and MTW wire is the fact that they both have the overlapping option of bare copper conductors. On the other hand, the second metal conductors options do not overlap, while THHN has an aluminum conductor, MTW has a tinned copper conductor. Another thing to consider, priorly mentioned is the fact that MTW wire is malleable due to the greater strand count while THHN wire cannot freely move due to the nylon jacket covering the interior. 

Machine Tool Wire (MTW Wire) Thermoplastic High Heat-Resistant Nylon (THHN Wire)
Sizing of Conductors 22 AWG to 1000MCM 14 AWG to 6 AWG
Type of Conductor Stranded Conductors Solid Conductors or Stranded Conductors
Material/Metal of Conductor Bare Copper or Tinned Copper Bare Copper or Tinned Copper
Insulation/Jacket Material Polyvinylchloride (PVC) Polyvinylchloride (PVC) with Nylon Jacket
Maximum Temp. 105° Celsius 90° Celsius
Maximum Volts 600 Volts 600 Volts


Z-Tronix MTW & THHN Wire Solutions

Puzzled a bit still, or we didn’t answer your question? Do not worry! Allow one of our many Z-Tronix wire and cable experts to assist you today by calling us at 562-808-0800. In the same manner feel free to explore our catalog and learn more or message us via