Portable measuring apparatus and method for the electric leakage of 4ct combination

A portable apparatus and a method for measuring an electric leakage of 4CT(Current Transformer) combination are provided to prevent accidents caused by the electric leakage by monitoring the leakage current in real time. A portable apparatus for measuring an electric leakage of 4CT combination includes a power unit(1), a sensor input unit(2), a multi switching unit(3), a DMM/ADC(Digital Multi Meter/Analog to Digital Conversion) unit(4), a CPU(5), a memory(6), an LCD screen(7), a key operation unit(8), and an USB(Universal Serial Bus,9). The power unit applies a power. The sensor input unit inputs phases of a transformer if the power is applied from the power unit. The multi switching unit receives and transmits a sense signal of the transformer from the sensor input unit to the DMM/ADC unit. The DMM/ADC unit converts the sensor signal of each phase into a digital signal, and transmits the converted sensor signal to the CPU. The CPU measures the digital signal of each phase periodically and calculates the measured data of each phase. The memory stores the calculated data of the CPU. The LCD screen displays a measured electric current of each phase and an electric leakage calculated in the CPU. The key operation unit operates the CPU with a key. The USB records and transports the calculated data conveniently.