| 摘要 |
<P>PROBLEM TO BE SOLVED: To effectively limit rush current flowing to a power rectifier circuit from an AC power supply, to short-circuit a current limiting element after rush current goes away, and to inexpensively and rationally improve life of a relay used for preventing power loss. <P>SOLUTION: A DC voltage detecting circuit 20 monitoring DC voltage after rectification of the power rectifier circuit 14 is installed. When DC voltage that the DC voltage detecting circuit 20 detects exceeds a prescribed voltage value, a coil Rc of the relay is not conducted. Only when DC voltage is not more than the prescribed voltage value, the coil Rc is conducted and a normally open contact point Rs is closed. The current limit element 13 arranged in series in an electric circuit from the AC power supply 10 to the power rectifier circuit 14 is short-circuited. <P>COPYRIGHT: (C)2008,JPO&INPIT |
