... digital transformer calibrating apparatus series3) HLS precise current transformer series4) HJS precise voltage transformer series5) FY current (voltage) transformer load box ... range 3kV,6kV,10kV,15kV,20kV,35kV,110kV,220kV5) standard transformer accuracy grade grade 0.01,0.02,0 ... testing volt-ampere characteristic of current transformer and no-load loss of voltage transformer to this system.2) Our ...