A breaker-phase-control switching system, comprising: a merging unit for converting waveform data of an electric quantity of an electric power apparatus into digital data, and transmitting the digital data added with time information to a process bus; a superordinate unit for transmitting a close or open command for a circuit-breaker to the process bus; a circuit-breaker control unit for electrically conducting a close coil or trip coil of the circuit-breaker, based on the waveform data and the close or open command, characterised in that the circuit-breaker control unit comprises a second internal clock synchronized with a first inside clock provided in the merging unit or the superordinate unit, a waveform-zero-point-calculation processing unit for calculating a current phase which shows a phase at present of an input electric quantity, based on absolute time kept by the second internal clock and on the waveform data, a predicted-breaker-operating-time-calculation processing unit for predicting a predicted operating time indicating an operating time from electrically conducting the close coil or trip coil of the circuit-breaker until close or open operation of the circuit-breaker is completed, and a command-output-timing-determination processing unit for determining a timing for electrically conducting the close coil or the trip coil, from the absolute time kept by the second internal clock, a preset target phase, the current phase calculated by the waveform-zero-point-calculation processing unit, and the predicted operating time predicted by the predicted-breaker-operating-time-calculation processing unit. a merging unit for converting waveform data of an electric quantity of an electric power apparatus into digital data, and transmitting the digital data added with time information to a process bus; a superordinate unit for transmitting a close or open command for a circuit-breaker to the process bus; a circuit-breaker control unit for electrically conducting a close coil or trip coil of the circuit-breaker, based on the waveform data and the close or open command, characterised in that the circuit-breaker control unit comprises a second internal clock synchronized with a first inside clock provided in the merging unit or the superordinate unit, a waveform-zero-point-calculation processing unit for calculating a current phase which shows a phase at present of an input electric quantity, based on absolute time kept by the second internal clock and on the waveform data, a predicted-breaker-operating-time-calculation processing unit for predicting a predicted operating time indicating an operating time from electrically conducting the close coil or trip coil of the circuit-breaker until close or open operation of the circuit-breaker is completed, and a command-output-timing-determination processing unit for determining a timing for electrically conducting the close coil or the trip coil, from the absolute time kept by the second internal clock, a preset target phase, the current phase calculated by the waveform-zero-point-calculation processing unit, and the predicted operating time predicted by the predicted-breaker-operating-time-calculation processing unit. a second internal clock synchronized with a first inside clock provided in the merging unit or the superordinate unit, a waveform-zero-point-calculation processing unit for calculating a current phase which shows a phase at present of an input electric quantity, based on absolute time kept by the second internal clock and on the waveform data, a predicted-breaker-operating-time-calculation processing unit for predicting a predicted operating time indicating an operating time from electrically conducting the close coil or trip coil of the circuit-breaker until close or open operation of the circuit-breaker is completed, and a command-output-timing-determination processing unit for determining a timing for electrically conducting the close coil or the trip coil, from the absolute time kept by the second internal clock, a preset target phase, the current phase calculated by the waveform-zero-point-calculation processing unit, and the predicted operating time predicted by the predicted-breaker-operating-time-calculation processing unit.