A power distribution box is a key part of any electrical system—it's the place where electricity from a main source gets divided and sent out to different circuits. You might also hear it called a PDU (Power Distribution Unit), distro, or distribution panel depending on the. Core idea: Distribution lines are the local electric circuits that carry power from distribution substations to customer service areas. Engineering use: Engineers review feeders, laterals, transformers, protective devices, voltage drop, loading, switching, and reliability. Electricity is carried from the transmission system to individual consumers. It acts like a hub or traffic controller, managing power flow to different areas or devices.