To provide a circuit breaker for a low voltage power contract, selectively displaying on a display abnormality of a plurality of objective portions to be monitored in the state of power failure of a wiring path so as to properly perform restoring work.

This breaker for the low voltage power contract is equipped with: a current sensor 13 to detect an excess current and a leakage current passing through the wiring path 11; a temperature sensor 14 to detect the internal temperature of a breaker case; and a voltage sensor 17 to detect the driving voltage of a CPU 15. The CPU 15 determines leakage, the excess current, abnormal temperatures, and abnormal voltages, based on the output of each of the sensors 13, 14, 17, so as to operate a trip coil 9 by outputting a trip command to a driving circuit 10. Electronic paper to hold display contents in the state of power failure is used for a self-holding display 6. The CPU 15 outputs the trip command to the driving circuit 10 after making the self-holding display 6 selectively display the leakage, the excess current, the abnormal temperatures, and the abnormal voltages, based on the result of determination.

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