Intro：GCS low-voltage withdrawable switchgear is widely used in power plants, metallurgical steel rolling, petrochemical industry, light industry and textiles, ports, terminals, buildings and hotels and other places as AC three-phase four-wire or five-wire system, rated voltage of 400V, insulation voltage of 1000V, frequency of 50Hz, rated current of 4000A and below power supply system for power distribution and motor centralized control.