The item is in accordance with standards of IEC61009.1 and BS4293 etc. Applying to the circuit of AC 50/60Hz,230V single phase,415V three phases and below it for industrial and mining enterprise,building trade,commerce and family. To mainly prevent electric fire and personal casualty accident caused by personal electric shock or leakage of electrified wire netting,this RCD is a current-operated,fast leakage protector of pure electromagnetic type. Which can break off fault circuit rapidly in order to avoid occurrence of accident.