In a 30-foot conduit run containing two conductors, what is the maximum percentage of cross-sectional area that can be occupied by the conductors?

The maximum percentage of cross-sectional area that can be occupied by conductors in a conduit is determined based on the National Electrical Code (NEC) sizing rules. For two conductors in a conduit, the code generally states that the total conductor fill should not exceed 31% of the conduit’s cross-sectional area.

When calculating conduit fill, it's important to consider that the permissible fill percentages vary depending on the number of conductors used. For more than two conductors, the allowable fill percentage decreases. For a run with only two conductors, using up to 31% of the cross-sectional area allows for both conductors to fit securely without overcrowding, which can lead to heat accumulation and potential safety hazards.

Adhering to this percentage ensures compliance with NEC requirements, promoting safety and efficiency in electrical installations. Therefore, knowing that 31% is the maximum fill for two conductors establishes a clear understanding of safe practices in conduit filling, supporting optimal performance and minimizing risks within electrical systems.