Patent attributes
A discharge lamp ballast apparatus includes a fault detecting section 9b of a discharge lamp 6; a first storing section 10 for storing a fault detected; a lighting delay detecting section 9c-3 for detecting lighting delay time from beginning of starting operation to lighting of the discharge lamp; a reigniting voltage measuring section 9c-5 for measuring a discharge lamp voltage immediately after switching of polarity applied to the discharge lamp according to AC lighting; a measuring section 9c-6 for measuring a period of time during which a current does not flow by detecting a discharge lamp current immediately after switching the polarity applied to the discharge lamp according to the AC lighting; a going out counting section 9c-4 for counting a number of times of going out by detecting going out during lighting of the discharge lamp; and a second storing section 9c for storing the lighting delay, reigniting voltage, period of time during which the current does not flow, and number of times of going out as operation records.
