| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply device that, if an abnormality occurs in alternating-current line voltage, gives an alarm informing of the abnormality and thus allows accidents to be prevented from occurring. SOLUTION: In parallel with normal operation for supplying electronic equipment with direct-current voltage, detection is carried out to determine whether the input voltage from an alternating-current line deviates from a normal voltage range. If the alternating-current line voltage does not reach a lower limit value or exceeds an upper limit value, the section between the output terminals N3 and N4 of a photocoupler PC1 is brought into off state, and a current is passed through a light-emitting diode LD1 and a buzzer BZ1. As a result, the light-emitting diode LD1 emits light, and the buzzer BZ1 is sounded, and the abnormality in alternating-current voltage is reported. COPYRIGHT: (C)2005,JPO&NCIPI
|
