... meter on-site.DFC~300 calibrator adopts Analog to Digital Conversion (ADC) be the fundamental principle, sample the voltage and current, ... according to demand, select clamp meter with 5A, 10A, 100A, 200A, 500A, 1000A, 2000A current span or flexible coil mutual ... 480V, automatic gear shift. 4. Current input: built-in current transformer: 1mA~12A, automatic gear shift. Clamp meter: 5A, 10A, 20A, 100A, ...