CLAMP MEASUREMENT APPARATUS FOR MEASURING WIDE BAND CURRENT

PURPOSE: A clamp measurement apparatus for measuring a wide band current is provided, which measures a high frequency AC current of several MHz from a DC current without disconnecting a line to measure the current flowing in the line. CONSTITUTION: A key input part(20) establishes a measurement range, and a hall effect device(240) measures a DC current. A conjunction coil(242) wound with a fixed turns of coils(244) generates an electromotive force according to the variation of a magnetic field formed by a current flowing in a line. An amplification/attenuation part(26) controls the induced electromotive force according to the setting of the key input part. An A/D(Analog/Digital) converter part(27) converts the high frequency amplified/attenuated analog signal into a digital signal. A FIFO memory(28) stores the converted digital signal, and a display part(22) displays a calculated current effective value and a current waveform. And a micom control part(21) controls the display part, and calculates the effective value by calculating the digital signal stored in the FIFO memory.