An electric charging apparatus comprising: a ground determination signal generating unit adapted to measure a current signal or voltage signal that is generated from power applied from a power supply unit, the ground determination signal generating unit adapted to generate a signal for determining whether the power supply unit is normally grounded on the basis of the current or voltage signal; a power control unit adapted to generate a power control signal on the basis of a ground determination detecting signal generated from the ground determination signal generating unit; and a power cutoff unit adapted to cut power supply to a target device to be charged on the basis of the power control signal, wherein the ground determination signal generating unit comprises a transformer transforming the generated voltage on the basis of the power applied from the power supply unit and a resistor, wherein the ground determination signal generating unit is adapted to generate the ground determination detecting signal on the basis of the current signal flowing in the resistor or the voltage signal applied to the resistor, wherein the transformer has a primary coil of which one end is connected to a line L of the power supply unit, and the other end is connected to a line N of the power supply unit and a secondary coil of which one end is grounded, and the other end is connected to one end of the resistor and the power control unit and wherein the other end of the resistor is connected to a line PE of the power supply unit and the power control unit, wherein the power cutoff unit comprises a plurality of relays, and the power to be supplied to the target device to be charged is controlled by on/off operations of the plurality of relays. a ground determination signal generating unit adapted to measure a current signal or voltage signal that is generated from power applied from a power supply unit, the ground determination signal generating unit adapted to generate a signal for determining whether the power supply unit is normally grounded on the basis of the current or voltage signal; a power control unit adapted to generate a power control signal on the basis of a ground determination detecting signal generated from the ground determination signal generating unit; and a power cutoff unit adapted to cut power supply to a target device to be charged on the basis of the power control signal, wherein the ground determination signal generating unit comprises a transformer transforming the generated voltage on the basis of the power applied from the power supply unit and a resistor, wherein the ground determination signal generating unit is adapted to generate the ground determination detecting signal on the basis of the current signal flowing in the resistor or the voltage signal applied to the resistor, wherein the transformer has a primary coil of which one end is connected to a line L of the power supply unit, and the other end is connected to a line N of the power supply unit and a secondary coil of which one end is grounded, and the other end is connected to one end of the resistor and the power control unit and wherein the other end of the resistor is connected to a line PE of the power supply unit and the power control unit, wherein the power cutoff unit comprises a plurality of relays, and the power to be supplied to the target device to be charged is controlled by on/off operations of the plurality of relays.