Open the terminal chamber cover, connect the cables through the cable gland to the terminals, ensuring both the internal and external ground wires are correctly connected. Wire. A cable distribution box is an electrical device used to collect, distribute, and protect electrical power. It is usually equipped with circuit breakers, fuses, terminal connectors, and other components. It takes the incoming power and safely distributes it to different circuits throughout your building. This helps stop wires from getting loose or damaged.