| 摘要 |
PURPOSE:To early discover the irregularity of the operating state of an AC motor by comparing the output signal of a rotating speed detector which is input through a P/I converter with an ACC signal output from a drive signal setter by an output detector, and operating, if there is an irregularity, the indicator. CONSTITUTION:The rotating speed of an AC motor 5 is detected by a rotating speed detector 13, input to an output detector 10 through a P/I converter 14, and an ACC signal is also input to the output detector 10. The output detector 10 compares the two signals to detect the difference therebetween. That is, a variable voltage variable frequency power source 7 inputs an output responsive to the ACC signal output from a drive signal setter 8 to the AC motor 5, and determines whether the AC motor 5 is operated at a normal rotating speed or not. If the difference between the ACC signal and the output signal of the P/I converter 14 falls within an irregularity range set by an irregularity range setter 11, an alarm is generated by the indicator 12. |
