| 摘要 |
PURPOSE:To detect many trouble-states such as an instantaneous voltage lowering power suspension accurately at high speed by combining the detected results of overload current, overcurrent in commercial power source, decrease in commercial power source, zero commercial current and the like, and judging the instantaneous voltage drop. CONSTITUTION:When a current ¦is¦ from a commercial power source 1 is higher than a specified value ISCOMP, when a voltage Vs of the commercial power source is lower than a specified value VSCOMP or when the current ¦is¦ is zero, a high level signal is supplied to a NOR circuit 13. When at least one value is at a high level, the specified judged output is sent into an AND circuit 14 having an inverted terminal. When the judged output is supplied from the NOR circuit 13 and the sum ¦is+ii¦ of the currents from the commercial power source and a compensating power source is lower than an overload current value ILCOMP, it is judged that there is an instantaneous lowering. In this way, various trouble states can be detected accurately at a high speed, and compensation responding time can be shortened. |
