The products accord with standard IEC60044-8, GB/T20840.8-2007, and can meet customer’s other special requirement. The products use Rogowski winding to test current, mainly used in ≤ 10kV switchgear, match with electric instrument, digital measure and protective equipment, can at the same time realize multi-functions such as measure, control, protection and data transmission etc, secondary open circuit can not produce high voltage.