Most longwalls employ either 2400 or 4160 volts to deliver higher power to the power centers and, subsequently, to the face equipment. This chapter addresses high-voltage power distribution for modern longwall sections. Electrical power is delivered from utility companies to the mine site, where it is then delivered underground to the longwall section and the individual face equipment. In order to reduce voltage drop during power transmission, high voltage power is used. The mine electrical distribution system consists of the following four parts: power source, conductors, load, and control devices. A substation refers to an electrical substation at the mine site. It is designed to receive the electric power furnished by a utility company by way of high-voltage transmission lines. The power center located outby the longwall section is used for transformation, rectification, switching, and protection in an electrical power system.