In the cable engineering of 10kV distribution network of power system, DFW series of high voltage cable branch box is an economic, reliable and convenient maintenance wiring mode. It replaces the problem of huge quantity of branches in the overhead lines of the power distribution system. Furthermore, it greatly reduces the line fault rate with its characteristics of full insulation and full sealing, which makes it an optional equipment for distribution network cable engineering. With simple, convenient, and flexible connection and combination mode, it replaces the ring network cabinet in some occasions. It saves the investment on equipment and cables, improves the reliability of power supply, and is widely used in commercial centers, industrial parks, and urban dense areas. If divided by different structural forms and types of cable joints, cable branch boxes can be divided into American cable branch boxes, European cable branch boxes, and cable branch boxes with switches.