| 摘要 |
PURPOSE:To enable to identify the release of a shortcircuit point by detecting the voltage of the output side of a breaker for protecting a power source. CONSTITUTION:In order to detect the voltage of a common bus of motor group 4(1), 4(2),...4(N), a voltage detector 9 is provided at the secondary side of a breaker 2 for protecting a power source. The output signal (d) of the detector 9 is inputted to a shortcircuit release detector 10. The detector 10 operates when a switching signal (a) to the breaker 2 for protecting a power source is an open command, and outputs a signal C when the shortcircuit point is released. Accordingly, when a shortcircuit defect occurs in the motor 4(1), the breaker 3(1) is tripped, and the motor group except 4(1) is continuously operated. |
