Where cables enter a distribution board from trunking, the cables must be protected from any sharp edges in order to comply with 522. Common methods of complying include deburring edges and using grommet strips or manufactured spacers. 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 is mainly used to isolate fault circuits, prevent overload, and ensure the safe operation of. Designers and installers must select a wiring system that avoids damage to the sheath and insulation of cable during installation, use and maintenance. Avoid installing in a humid and corrosive environment to prevent equipment damage.