PURPOSE: To reduce the size of a circuit breaker and reduce the cost thereof by performing a tripping operation through a voltage tripping circuit without providing a dedicated tripping device.
CONSTITUTION: The excess current of a main circuit 5 is detected by an excess current detecting circuit 7 based on detected current from a current transformer 6a, 6b, or 6c. The excess current detecting circuit 7 sends a trip signal to a thyristor 10 so as to energize a tripping device 9. A voltage tripping circuit 11, receiving external signals to external power supply input terminals 12a, 12b, energizes a tripping device 9 via a diode 13 according to the value of the voltage signal. Thereby, it is possible to perform an excess current tripping operation and a voltage tripping operation by one tripping device 9.
| JP3106977 | CIRCUIT BREAKER |
OZAKI MASA
SAKANO MAKOTO
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