What is the minimum depth required for a pull box in a wet location with a 3½ in. raceway?

The minimum depth required for a pull box in a wet location with a 3½-inch raceway is specified to be 5 inches. This requirement is outlined in the NEC to ensure that there is sufficient space within the pull box for ease of wire pulling, securing connections, and allowing for potential expansion of wires. A pull box with inadequate depth could lead to stress on the conductors and compromise the integrity of the installation.

Design considerations in wet locations are particularly important due to the increased risk of moisture affecting electrical systems. Therefore, when determining the depth of pull boxes in these locations, the NEC sets specific requirements to maintain safe and efficient electrical installations. The designation of 5 inches takes into account the dimensions of standard raceways, ensuring compatibility and functionality within the installation parameters.

In contrast, lesser depths such as 3 inches, 4 inches, or 6 inches are either insufficient to accommodate the necessary conductors or exceed the standard requirements for effective installation. The specified depth is critical for maintaining system safety and operability in variable conditions.