S200B double clamp digital phase meterIs a multi-functional instrument developed specially for on-site test. Featured with high precision, good stability, less power consumption and easy operation, it measures directly A.C. Voltage and A.C. Current even when the tested circuit is not opened, as well as phase between two voltages, two currents and the voltage-current. In addition, it measures indirectly power factor and power of the circuit, identifies three-phase sequence, wiring group, inductive and capacitive circuit of transformer, tests secondary circuit and the busbar differential protection system, tells the phase relation between different CT groups of differential protection, examines whether the wiring of watt-hour meter is correct, and checks and repairs circuit equipments, etc. The instrument has huge LCD screen, with letters reaching 40mm in height and looks greatly clear thanks to the backlight design. The instrument is applicable to electricity, petrochemical engineering, metallurgy, railway, meteorology, industrial and mining enterprises, academic institutions, colleges and metrological sectors, etc.