| 摘要 |
The present invention relates to an apparatus for detecting an open phase of three-phase input power supply, including the following elements: a three-phase half-wave rectifier for half-wave rectifying each phase voltage of a three-phase input power supply; a charging unit for charging the voltage rectified in a three-phase, half-wave rectifier; a comparison unit for comparing the voltage charge in the charging unit with a reference voltage; and a photo coupler, which operates based on a comparison result of the comparison unit in order to indicate whether the image is generated, and which outputs an indicating signal. According to the present invention, the apparatus can accurately detect the input phase regardless of an operating state of the apparatus to use a three-phase AC power source, such as an industrial inverter, and which can reduce thermal stress by lowering the current required for driving a comparator and the photo coupler. |
