Learn how to install a distribution box safely and correctly. Covers wiring, placement, standards, and expert tips for a compliant setup. Once inside the box, the incoming power is connected to bus bars, which are metal strips that conduct electricity. Depending on the system design, the electricity is regulated to usable voltage levels, such as 120V or 240V. This step ensures. In the world of electrical installations, the term DB box —short for Distribution Board box —refers to the central unit that distributes incoming electrical power to multiple outgoing circuits in a building. Distribution boxes, or electrical junction boxes as they are sometimes called, play a vital role in electrical systems. Identify the dual power switch (if any): Understand the working principle and.