What is the conduit capacity for one cable calculated based on the formula given?

The correct calculation for conduit capacity is based on the maximum fill requirements set forth by the National Electrical Code (NEC) or similar guidelines. The proper formula takes into consideration the diameter of the single cable (d) and provides a percentage of allowable fill (D) based on a specific factor.

In this case, the capacity of a conduit for one cable is correctly represented by the formula that incorporates a 53% fill ratio, suggesting that only 53% of the conduit space can be filled to maintain safety and accessibility. This ensures sufficient space for heat dissipation and allows for future cable additions or maintenance without damaging existing cables.

Additionally, the formula involves the calculation of the total space available within the conduit, which is represented by the square root of the sum of the squares of the diameters. This geometric consideration is intrinsic to calculating how cables are arranged within a cylindrical conduit.

Understanding these principles is crucial for proper installation and adherence to electrical codes, ensuring operational efficiency and safety in audiovisual installations.