Electrical Code Calculations Level I Practice Test 2026 – Your All-in-One Guide to Master Every Exam Topic!

To determine the correct ampacity for a 2 AWG THW copper conductor in a raceway at 30°C, one must refer to the applicable electrical code tables, specifically the National Electrical Code (NEC) tables for conductor ampacities. The standard table for ampacity provides values based on conductor size and insulation type, taking into consideration different ambient temperatures and installation conditions.

For a 2 AWG copper conductor with THW insulation, the ampacity is listed at approximately 150 A at 30°C ambient temperature when installed in raceways. This value is based on the standard reference for the temperature range and does not require adjustment as the 30°C temperature does not exceed the usual rating conditions.

This fundamental understanding of conductor ampacities, along with the specifics of the installation conditions (such as raceway use), leads to recognizing that 150 A is the correct value for this scenario.