What is the amperage rating for No. 1 aluminum THW?

What is the amperage rating for No. 1 aluminum THW?

• A. 75 amps
• B. 100 amps
• C. 125 amps
• D. 150 amps

Answer: (B)

The correct amperage rating for No. 1 aluminum THW (Thermoplastic heat and water-resistant) wire is indeed 100 amps. This wire is commonly used for a variety of electrical applications, including service entrance and feeder circuits, and its ampacity is determined based on various factors, including the type of insulation, the ambient temperature, and how the wire is installed.

The National Electrical Code (NEC) provides guidelines for determining the ampacity of conductors, which is essential for ensuring safe and effective electrical installations. For aluminum conductors, the ampacity is generally lower than that of copper due to the differences in material properties.

It's important to understand the specific application and installation conditions when selecting wire size and amperage rating, as exceeding the rated amperage can lead to overheating and potentially cause a fire hazard.