Which table in Chapter 9 of the NEC is used to determine the approximate area of a compact aluminum conductor with XHHW insulation?

In Chapter 9 of the National Electrical Code (NEC), Table 5A provides specific information about the approximate area of conductors made of aluminum with various insulation types, including XHHW insulation. This table is tailored to help electricians and engineers determine the appropriate conductor size based on the type of conductor material and insulation, which is crucial for ensuring that electrical installations meet safety and performance standards.

The significance of using Table 5A lies in its detailed presentation of conductors classified according to their material composition and insulation type, helping users quickly identify the surface area required for proper load calculations. This ensures that the conductor can safely handle the expected electrical loads while minimizing risks such as overheating.

The other tables in Chapter 9, while also useful for various electrical calculations, do not specialize in the specific requirements for aluminum conductors with XHHW insulation like Table 5A does. Thus, it is the best choice for determining the area of compact aluminum conductors under the specified conditions.