What is the maximum operating temperature for conductor type THWN?

For conductor type THWN, the maximum operating temperature is indeed 167 degrees Fahrenheit. This type of wire is evaluated according to the National Electrical Code (NEC) standards, which classify conductors by their thermal characteristics. THWN stands for Thermoplastic Heat and Water Resistant Nylon-coated wire, and its temperature rating reflects its ability to perform safely under specified conditions.

The 167 degrees Fahrenheit rating indicates that while THWN can operate at or below this temperature, it is important for safety and efficiency that this limit is not exceeded. If the conductor were to be operated above this temperature, it could lead to insulation degradation, increased resistance, and potentially hazardous conditions such as overheating or fire. This characteristic makes THWN suitable for various applications, especially in environments where moisture is a concern, while also requiring adherence to specific thermal limits.