You have so many options when it comes to electrical wiring for your home or business. Among them, the most popular choices are THHN wire and XHHW wire.
But how do you know which one meets your requirements in the THHN vs XHHW battle?
XHHW wire has more insulation capacity than THHN wire. Besides, XHHW is more suitable for small to large applications, whereas THHN is only applicable to small projects. XHHW can resist current leakage more effectively and last longer, offering more temperature rating and flexibility than THHN wire.
In this article, I will compare these 2 types of wire in terms of 7 key factors. By the end, you will definitely better understand which type of wire is right for your needs.
THHN Vs XHHW Wire: At A Glance
| Comparison factor | THHN Wire | XHHW Wire | Winner |
| Wire Insulation | Thermoplastic Low insulation capability | Thermoset Substantially Higher insulation capability | XHHW Wire |
| Jacket Material | Polyvinyl Chloride (PVC) It cannot resist as much pressure and stress as the XHHW wire | Cross-linked polyethylene (XLPE) It can withstand stress, abrasion, and other wear and tear. | XHHW Wire |
| Temperature Rating | 90° C in dry locations 75° C in wet locations | 90° C in dry and wet locations | XHHW Wire |
| Installation temperature (min) | -10°C | -40°C | XHHW Wire |
| Ampacity | 20 to 554 according to wire length | 25 to 500 according to wire length | THHN Wire |
| Voltage Rating | 600V | 600V | Both |
| Conductor | Copper conductor Stranded or solid | Copper or aluminum | Both |
| Resistance to Leakage Current | Low | Very High | XHHW Wire |
| Flexibility | The nylon jacket over the insulator makes it quite hard to bend | Thicker but easy to bend and use | XHHW Wire |
| Longevity | Made of pure copper Covered by heat-resistant Nylon-coated | Made of Copper and aluminum Copper wires are more durable | XHHW Wire |
| Affordability | Reasonable than XHHW $0.22/ft. approx | 5-20% more than its THHN$2.75/ft. approx | THHN Wire |
| Best fit for | Low tension applications | Both high and low-tension applications | XHHW Wire |
THHN Vs XHHW Wire: 7 Key Differences
Before jumping to the comparison section, let’s have a look at what THHN and XHHW mean.
THHN stands for Thermoplastic(T), high heat-resistance(HH), and Nylon coated (N).
On the other hand, the X of XHHW defines the Cross-Linked Polyethylene (XLPE), HH for High Heat-Resistant, and W for water resistance.
Now time for an in-depth discussion of the major difference between THHN and XHHW wires. Without any further delay, let’s dive into it.
Wire Insulation
Wire isolation of THHN wires is made by thermoplastic, whereas XHHW comes with Thermoset.
Both are made of polymers, but thermoplastic tends to melt down under high heat, whereas thermoset plastics can stay solid, retaining their actual form under the same situation.
As a result, the ability of wire insulation of THHN is lower than the XHHW wires.
So, XHHW wire insulation can prevent current leakage from the wires and protect them from extra rough conditions.
Winner
So, XHHW is the winner for better wire insulation.
Jacket Material
There is a thick Polyvinyl Chloride (PVC) jacket over the thermoplastic insulation of THHN wires.
On the flip side, the XHHW wires have a more stable and durable cross-linked polyethylene (XLPE) jacket.
So, XHHW wires are more protected and long-lasting. Because the cross-linked polyethylene or XLPE has greater resistance ability to stees or abrasion, it can withstand wear or tear or any other damage.
In that case, Polyvinyl Chloride or PVC is not as protective as XLPE. They have less ability to withstand stress or pressure. They tend to tear or damage.
Winner
XHHW wires will be wise for their greater protection ability and durable jacket material.
Ampacity
The ampacity for THHN is more than XHHW wires.
Ampacity is the maximum current flow that the wire conductor carries. That is also related to the wire length, temperature rating, and voltage.
However, the voltage rating is 600V for both wires.
According to the ampacity chart, the ampacity for THHN wires varies from 20 to the highest 554 according to wire length.
Using a 14 gauge THHN wire can flow a 20 amp current without exceeding the temperature rating. The ampacity will be 554 amp when you use 1000 gauge wires.
On the other hand, you can get a 25 amp current for 12 gauge XHHW wires. The highest current flow for 1000 gauge is 445amp which is lower than the THHN wire.
Winner
Overall, the ampacity of THHN wires is more than XHHW wires.
Temperature Rating
XHHW can operate at a maximum temperature in both dry and wet conditions.
The temperature rating indicates the maximum withstand temperature of wires. That can vary wire to wire conductor material insulation type, application, e.g., outdoor or indoor, etc.
THHN wires have a stranded or solid conductor. The maximum operating temperature is 90° C in dry conditions. The temperature should not exceed 75° C in wet conditions like coolant, oil, etc.
But for XHHW wires, the maximum operating temperature is 90° C in both wet and dry locations. Besides, the installation temperature is -40°C for XHHW wire, whereas the THHN can be installed at min -10°C.
Winner
As XHHW wires have more temperature rating than THHN in wet conditions. So, XHHW is the winner.
Longevity
The longevity depends on the material, insulation, manufacturing process, usability, and resist capacity.
In that case, THHN copper wires are more durable and stable and perform better than XHHW aluminum wires.
However, the XHHW wires are also made of copper so they will be more well-performing for years.
Also, the insulation of XHHW wires is water-resistance. So it is more capable of resisting corrosion, moisture, and damage.
Winner
So, if we consider longevity, then XHHW wires are the winner.
Flexibility
XHHW wires are more flexible to use.
Though these wires are thicker than the THHN wires. But their XLPE insulation is easy to bend and more flexible to use.
On the other hand, PVC insulation is less flexible. Plus, the THHN wires come with a Nylon jacket over the PCV insulation. That makes it slightly hard to bend.
Again, XHHW wires can be used in both wet or dry outdoor or indoor applications.
Winner
If you’re looking for versatile, easy-to-flex, and use wires, XHHW is a good choice.
Affordability
The price range depends on the quality of the wires, materials, insulation ability, protection, safety, thickness, application, and many more.
Generally, the price range for a 1-foot THHN wire is approximately $0.22 USD, and the average price range of XHHW wires is $2.75/foot.
This means you need to spend 5-20% extra bucks per foot on XHHW wire.
Winner
In terms of affordability, THHN provides a more affordable deal.
THHN Vs XHHW Wire: Which One To Go For?
These types of wire have unique properties and benefits that make them well-suited for different purposes.
Now we will go over some of the most common uses for each type of wire so that you can make an informed decision about which one is right for your next project.
Choose THHN Wire If You Need Wire For
- Any low-tension applications
- External power sources
- Automobile
- Machine tool
- control wiring
- Signaling source
Choose XHHW If You Need Wire For
- All low and high-tension project
- Industrial applications
- Residential building
- Institutional and Commercial building application
Though XHHW wires are a little bit expensive where THHN is an affordable option but has less durability and less leakage resistance capacity.
FAQs
Is XHHW Suitable For Outdoor Use?
Yes. XHHW is suitable for wet or dry outdoor or indoor use. XHHW is a type of electrical wire that is resistant to moisture, heat, and sunlight, making it ideal for use in harsh environments.
Can THHN Be Used On A Wall?
Yes, THHN wires can be used in a wall. These wires are suitable for interior walls and surface wiring above the ground to contain lights or electrical panels.
Can XHHW Be Used In Cable Trays?
Yes, XHHW can be used in cable trays. Because it is a safe, reliable, and code-approved insulation for use in wet or dry locations. When used in cable trays, it is important to ensure that the conductor is properly supported and that the correct ampacity rating is used.
