PURPOSE: An apparatus for measuring 3Φ current is provided to simplify a structure and reduce the manufacturing cost by receiving simultaneously 3Φ current of a 3Φ distribution line and measuring selectively R-phase, S-phase, and T-phase current. CONSTITUTION: An apparatus for measuring 3Φ current includes an R-phase connection terminal, an S-phase connection terminal, a T-phase connection terminal, a first current transformer, a second current transformer, a slide switch, an indicating member, a deflection coil, and a variable resistor. The R-phase connection terminal(10) is electrically connected to an R-phase transmission/distribution line. The S-phase connection terminal(20) is electrically connected to an S-phase transmission/distribution line. The T-phase connection terminal(30) is electrically connected to a T-phase transmission/distribution line. The first current transformer is used for measuring the current of the R-phase transmission/distribution line. The second current transformer is used for measuring the current of the T-phase transmission/distribution line. The slide switch(40) is used for performing a switching operation to detect the S-phase current by synthesizing the R-phase current and the T-phase current. The indicating member is used for indicating the R-phase current, the S-phase current, and the synthesis current of the R-phase current and the T-phase current. The deflection coil is used for driving the indicating member, clockwise or counterclockwise. The variable resistor is used for limiting the amount of current and controlling a null point of the indicating member.
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