Primary distribution refers to high-voltage systems that transport power over long distances, while secondary distribution involves low-voltage systems delivering power directly to homes and businesses. The general method of supplying bulk power to buildings, factories or other complexes is by means of an MV supply, usually at 10 kV, occasionally at 6. Electricity is carried from the transmission system to individual consumers. Distribution substations connect to the transmission system and lower the transmission voltage to medium voltage ranging between 2 kV and 33 kV. The distribution box (DB box) helps safely and efficiently distribute electrical power. This ultimate guide explains what a distribution box does, its internal components, common types, real-world applications, and how to select the right DB Box for your project.