In the following go-to guide to THHN wire we will consider answers to the following questions:
– What Is THHN Wire?
– What Is The Construction Of THHN Wire?
– What Are The Specifications Of THHN Wire?
– What Are The Typical THHN Wire Applications?
– What Other Types Of Building Wire Exist?
We will provide short, clear answers to each question without delving into too much detail. Allow us to start with the key question and then move on to the others in turn.
What Is THHN Wire?
THHN is the abbreviation for Thermoplastic High Heat-Resistant Nylon. This building wire is resistant to gasoline, oil, and abrasion.
What Is The Construction Of THHN Wire?
There are several key factors related to the construction of THHN wire. These are as follows:
– It is a single-conductor wire
– It is often constructed of bare aluminum or copper
– It has thermoplastic insulation (this is usually PVC)
– It is highly durable thanks to its Nylon Jacket
– It is resistant to gasoline, oil, and abrasion.
What Are The Specifications Of THHN Wire?
You will often find that this building wire is dual rated, in which case it will bear the name THWN Wire. This abbreviation stands for Thermoplastic Heat and Water Resistant Nylon. With this dual rating the maximum temperatures are as follows:
– Up to 90 degrees in dry areas
– Up to 75 degrees in wet areas
The voltage rating of this building wire is always 600V, this is not dependent on the dual rating.
Depending on the choice of THHN/THWN, various compliances can be met. For instance, many choices will meet UL Styles 83 and 1063 and those with a stranded construction will meet the standards for UL MTW (machine tool wire). If RoHS compliance is required, there are THHN Wires available that can provide the necessary specifications for your needs.
What Are The Typical THHN Wire Applications?
The typical and, in fact, likely the most common use of this type of building wire is that of carrying electrical currents to external power sources within a building. However, its use can be wide and varied. For instance, it can be used in tools and appliances as well as machines and control circuit wiring, hence being viewed as a general-purpose wire. Other uses of THHN Wire include various recognized raceways, for instance in a cable tray.
However, it is crucial to note that THHN Wire is not a suitable choice for outdoor use. In addition, it should not be used for direct burial applications, This is because toxic gases can be released from the jacket should it be exposed to a flame.
What Other Types Of Building Wire Exist?
While THHN is a popular choice of building wire, other common types exist as well. For instance, TFFN Wire is commonly used for instances where a building wire is required. This abbreviation TFFN means Thermoplastic Flexible Fixture Nylon. In the same way that THHN Wire featured a nylon jacket and PVC insulation, TFFN Wire provides the same. That being said, it is important to note that TFFN Wire cannot be used in locations that are wet. Perhaps one of the key differences between THHN Wire and TFFN Wire is that TFFN Wire is in the classification of being a fixture wire.