According to national standards, the wall thickness of the low-voltage distribution box should not be less than 1. For distribution boxes that handle only lighting circuits or small power loads, if the incoming wire size is less than 10 square millimeters and the number of circuit switches is fewer than 20, the width of the box should be calculated by summing the width of the switches and adding an additional. These boxes, typically 4 inches in diameter with depths ranging from 1-1/2 inches to 3 inches, are commonly used for mounting light fixtures on ceilings or walls in US residential settings. The octagonal shape provides convenient points for securing mounting brackets for light. Generally speaking, the thicker the box, the better its endurance, heat resistance, and safety. The article includes table. Wall distribution boxes in their standard version are electrical equipments of smaller size deigned for placement of devices and other elements of instrumentation and control equipment. Check for proper IP/NEMA ratings and material quality.
[PDF Version]