| 摘要 |
PURPOSE:To prevent the further extension to other places of an accident positively by a method wherein the abnormality of the voltage at the input side of a rectifier is detected and protective operation is concucted or an alarm is given. CONSTITUTION:The voltage at the input side of a rectifier Rf is detected by means of a voltage detecting circuit 6, and compared with constant voltage fed by a constant-voltage generating circuit 8 by means of a comparison circuit 7, protective operation is conducted and an alarm instruction device 9 conducts protective operation by signals supplied from the comparison circuit 7 when the voltage at the input side of the rectifier Rf becomes abnormal, and an alarm is given. Thus, protective operation is conducted and the alarm is given when an open phase or a short is generated at the input side of the rectifier Rf. |
