JN22-36 Indoor earthing switch is applicable for three-phase AC power system of rated voltage up to 7.2KV~40.5KV and frequency 50/60 Hz, it widely used in many fields such as power plant, transformer substation, petrol chemical industry, metallurgy, manufacturing industry, airport, residential area, etc, for mounted at in frequency operation service indoor air insulating switchgear like tyoe KYN28 or KYN96, ABB type ZS series, etc.