| 摘要 |
PROBLEM TO BE SOLVED: To test the operation of a breaker to trucking short circuits. SOLUTION: This tracking-ready breaker is provided with a test circuit. In the test circuit, by the control of an MPU 13, a pulse circuit 18 outputs a pulse waveform of a frequency different from the electric source waveform of a current passing through wiring paths 4 when a test button 17 is turned on. A contact of an instantaneous opening/closing circuit 19 formed by passing a serially connected contact and a current limiting resistor through a current transformer 5 and connecting to the wiring paths 4 is continuously opened and closed by a pulse signal of the pulse circuit 18 to extract the electric source waveform on a random basis to generate a pseudo-tracking current. |
