| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a means capable of promptly recognizing that a lighting device is abnormal without giving uneasy feeling to a worker and a user during construction, by suppressing probability that the lighting device gets out of order when a high voltage with a prescribed magnification is impressed in comparison with normal time as in the case of incorrect connection of three phase four wire wiring. <P>SOLUTION: This discharge lamp lighting device is to supply high frequency power to a discharge lamp load FL by converting a commercial power supply Vin to a high frequency, and has a detection means (comparator CP1) to detect that a high voltage with a prescribed magnification (√3 times for instance) in comparison with the normal time by the incorrect connection of power supply wiring has been input, and an abnormality protecting circuit 3 to suppress stress on the circuit components of the discharge lamp lighting device by its detected output. The abnormality protecting circuit 3 is used as a notification means to notify that something is apparently abnormal during construction, and does not light the discharge lamp load FL although it is in an energized state by interrupting a switching element Q4 inserted in the main power supply line. <P>COPYRIGHT: (C)2009,JPO&INPIT |
