| 摘要 |
PURPOSE:To provide a monitor for a motor circuit comprising an NFB, a CT, a contactor, and a motor arranged sequentially on a feeder from the power supply side wherein normal and abnormal current values are measured and stored at the time of power interruption and an abnormal state is evaluated based on thus stored current values. CONSTITUTION:A current detecting means 6 detects current flowing through a motor circuit and a maximum peak value thereof is held in a peak hold circuit 13. A power interruption detecting means 12 detects power interruption of the motor circuit while an operating means 7 normally operates a current value to be fed to a motor based on a detected current value and extracts an overcurrent value from thus detected current values. Upon function of the power interruption detecting means 12, an overcurrent value and the maximum peak value are delivered from the operating means 7 and stored in a memory means 14. |
