... pursuant to accuracy class of the calibrated electric energy meter. 9. Measure CT variable ratio, ratio error, angle error and polarity ... Current input: built-in current transformer: 1mA~12A, automatic gear shift. Clamp meter: 5A, 10A, 20A, 100A, 200A, 500A, 1000A and 2000A for selection ... error 0.2´; ratio error 0.02%.14. Accuracy for PT, CT secondary load measurement: Class 1.0. Measurement range: ...