The inflatable ring main cabinet is a kind of cabinet that realizes inflatable type. It is connected by the medium voltage dividing room. The load switch cabinet can be used for ring main power supply. For the power supply of the medium voltage terminal substation, the power supply departments in various regions have different specifications and requirements for the transformers that are allowed to use the load switch and fuse for maintenance. Load switch is an excellent load switch realized by many users in recent years. In addition to the advantages of long electric life and strong breaking force, it has the same advantages as vacuum load switch. Load switch is a kind of switching device with simple arc extinguishing equipment.

The load switch as the insulation and arc extinguishing medium is called the load switch, which can be used to turn on and off the load current and overload current. The short-circuit maintenance and overload maintenance of the high-voltage ring main cabinet and the high-voltage side of the transformer are undertaken by the high-voltage current limiting fuse. The high-voltage switch cabinet with load switch and fuse combination is called ring main cabinet, which is mainly separated from the switch cabinet with circuit breaker. The high-voltage circuit is generally controlled by load switch or vacuum contactor, and is equipped with high-voltage fuse for maintenance. The system generally uses the ring network for power supply. The high-voltage switch cabinet used by the outdoor ring network cabinet is generally called the ring network cabinet. Therefore, the section of the high-voltage bus of the ring main cabinet shall be selected according to the sum of the load current of the distribution substation and the through current of the ring network.