What is the minimum calculated height of a pull box where all conductors enter the bottom and exit the right side?

The minimum calculated height of a pull box is determined based on the requirements set forth in the National Electrical Code (NEC) for ensuring sufficient space and access for the conductors, particularly in a configuration where all conductors enter from the bottom and exit from the side. In this specific scenario, it is critical to accommodate the bending radius of the wires and to allow for proper installation and maintenance without risking damage to the conductors.

The calculated minimum height of 42.5 inches aligns with the need to maintain the necessary clearances and protection for the conductors. This height allows for adequate working space, ensuring that electricians can perform their tasks safely and effectively. If the pull box is too low, it might not meet code requirements for safe access and the functionality of the installation.

The other heights, while they may seem plausible, exceed the minimum requirement established for such configurations. The NEC sets these guidelines to ensure safety and efficiency in electrical installations. Thus, selecting the height of 42.5 inches is the most appropriate choice for a pull box under these conditions, as it is the minimum height required to effectively support the entry and exit of all conductors while complying with safety standards.