The medium voltage isolating switch (also called MV disconnector) is an important switching appliance in the electrical system of power plants and substations and needs to be used in conjunction with medium-voltage circuit breakers. The isolation switch is suitable for installations with AC 50Hz and a rated voltage of 10~36KV. It is used to connect, cut off or convert the line under the condition of voltage and load of high-voltage equipment.

Its main function is that the high-voltage isolation switch ensures the safety of high-voltage electrical appliances and devices during maintenance work, and plays the role of isolating voltage, but it cannot be used to cut off, input loads current, and break short-circuit current. It does not have arc extinguishing function, only can be used for certain switching operations that do not produce a strong arc.

According to its installation location, it is separated into indoor isolating switch and outdoor isolating switch. Due to the number of insulating pillars, it is divided into single-column type, double-column types, and three-column type. There is optional equipment for each voltage level. It can also reliably isolate the part of the high-voltage power distribution device that needs to be powered off from the live part to ensure the safety of maintenance work. The contacts of the high-voltage isolating switch are all exposed to the air and have obvious disconnection points. The isolating switch has no arc extinguishing device, so it cannot be used to cut off load current or short-circuit current. The medium-voltage isolating switch is an important switching appliance in the electrical system of power plants and substations and needs to be used in conjunction with medium-voltage circuit breakers.