Features: 1) Intelligent equipment 2) Tests CT /PT voltage and current 3) Voltage-current characters tester the tester ... automatically step-up/increase current, and display the test result about volt-ampere characteristics curve, ratio and polarity. Data-saving and ... .Complete-function: to test the volt-ampere characteristics of CT/PT, ratio, polarity, error curve of 5% ,10%, primary current, ACTV ...